Found this CRT projector at a garage sale. It was only 10$ and I hoped it would be something simple that was wrong with it.

After cleaning the entire thing and powering it on. You can hear a loud crinkly/static noise coming from the HV area right after powering up. Like most Tv's do (I think this is normal, and mention it for elimination from troubleshooting)

The other thing I hear is a buzzing/ticking from near the power supply's transformer. This starts a couple seconds after powering on. Either the power supply is screwy. Or something else is making the power supply trip out. One thought was the large 680uf 200 volt capacitor. It's large and looks just slightly bulgy. Anyone think a 28 year old cap would dry up?

I have also seen the crt's flash when you flick the power off. (mainly the red one)

I post this here because the projector is basically a color TV but it has a CRT for each color. And should be similar in trouble shooting.

Here's a picture of a working one. Anyone remember ever watching one of these?
http://farm4.static.flickr.com/3248/2288759042_ea860c5e4c.jpg?v=0

Thanks for reading
Rudy

Alright Regardless of what I have said I now think it is an HV problem.

Using a fluorescent bulb in the dark I put it near the heavily insulated Hv lines. That go to the suction looking cups on the CRTs. When you flick power on the bulb glows momentarily. I could also see some HV leakage arcing.(Should this happen at all) Then it stops glowing. Once again when you power it off, the bulb glows momentarily.

Also when you power off the projector the CRT's often give there only sign of life at that point with a quick flash. Much like the bulb did when turning it off. This leads me to believe HV failure.

I have a few questions about the HV wires. Do these wires slowly loose there ability to insulate?

Do these wires change resistance like spark plug wires?

Or should I be more focused on the HV transformer area and horizontal deflection sections of this projector?
Any one had a similar problem with solid state?

Thanks for your time
Rudy

Okie doke

I got this bad boy singing! But it's not total victory yet. The green tube is not lighting up at all. But both blue and red are working strong.

I'm guessing i'll need a replacement crt or rebuild. Does any one know of a place I could get this done Or find the new one?

Thanks Rudy

I'll post pics once my computer will let me

I remember these Zenith projectors back in the 80's.Not equal to most of the data grade projectors of the same period, but good enough to give you a large picture (if you didn't mind the scan lines). I think most of these were basically video grade only, but I could be wrong.

As far as hunting down the problem with the green gun, you could start here and ask Curt
http://www.curtpalme.com/
If it's a crt rebuild,Curt could direct you to a company that still does this.

or you could take your chance with the AVS forum (CRT projectors).

swap the crt boards from the red to green or blue to green i mean unplug the green board an move either the red or blue over to the green tube. dont disconnect the connectors on any board just move the red or blue to the green crt and see if you have video. you might have bad green drive from the chassis or a bad green crt board. steve

beleive it or not I've already sent curtpalme an email, he hasn't replied yet though.

Swapping the crt boards is an excelent idea. I planned on checking all the voltages on all three boards but swapping them for more instant and rock hard results sounds even better.

I'm hoping the tube is OK. I don't think finding it would be very easy. And rebuilding from what I've heard is rare and expensive.
Thanks
Rudy

I know that you already know this, but i will say it in case you don't. Crt projectors usually have switches to turn off individual crt's during the set up and alignment process. sometimes a previous person might have flipped switches just because they can. Also Does the green crt filament light up? swapping out the crt boards is also a great idea as mentioned before.

OOOOOO switches eh? I did not know this, but it makes sense that it would.

I will take a good look over for some switches.

And yes all three filaments are glowing red as they should be.

And don't asume I know anything! I am only 17 and very clever and know alot about electronics. And have fixed and worked with tubed devices mostly.(amps, tvs)
This is my first solid state challenge. But it's the same principals.
And I am more than eager to learn.

So everything you guys tell me helps.
Thanks again
Rudy

Getting a tube for that might not be too bad-I think there are a few places that do rebuilding on them. Since they are monochrome and rather small they wouldn't be so hard to do. I have seen projector crts on ebay on a regular basis.

I know where I can get a Panasonic similiar to this-the guy said I could have it, but I really don't have the room.

OK so the green is working. But it is not very bright.

Dead tube or other....???

It was probably working the whole time. I just never starred directly into it.

I tried switching the baords around but it proved to be difficult with tied in wires that didnt wanna move that freely.

But I hope the fact that it is actually working just not bright enough will bring some more conclusions...like weak crts....??(Also I noticed that the green focus or something was set to "high" unlike the red and blue that were set to medium)
Also the picture is upside down. Maybe this has to do with distance or something.....I donno

Rudy

Have you tried injecting a video signal into this and projecting it onto a wall or something to see how it looks? You might be able to turn up the screen control on the green gun if that is even needed and get a decent picture out of this thing. Never know, you just might end up with a great ten dollar find.

Yes I tried playing some Friends.

The red plays strongly. And blue is there.
But the green plays much to weakly to get any effect from it.
And I cannot find any brightness control on this unit.

And still the picture is upside down. Was this thing ever mounted upside down?

Rudy

Yes, It probably was a ceiling mount, but most projectors i've seen have a way to reverse the picture, some had a menu option you could select, some like my antique Barco V-star you had to individually reverse connectors on the yokes.

I have a Provision 750 which is a Zenith comercial projector. To change the settings for floor/ceiling, and front/rear projection there is a board with jumpers (I think) that are changed. All you are doing is changing the yoke connections though. You really need a service manual to help with setup. There may be a service menu that will allow you to turn down the red and blue to match green. This will reduce brightness, but may make a useable picture in a dark room. These weren't very bright to start with. You may be able to find a complete set of projection tubes on ebay which would be a good idea. If you replace only green you will likely not be able to get good gray scale. And by the way do not look directly into the front of the projection tubes, it could harm your eyes.

Bill R

Since this is your first experience with a front projector, you really should try to find a user/install manual or seek advice from someone that knows this particular projector. If your intention is to learn how to fix them,seek some help from those who have the experience. This is not to say that there isn't anyone here that can help you, but since you are a novice, you can really cause some further damage or hurt yourself if you go at it willy nilly.I speak from experience..

The green gun gets most of the work in a 3 crt configuration.Maybe this is why it's weak. There are some G2 controls on projectors, but I'm not certain about the Zenith you have. Also, there usually is a switch that turns off each gun for sizing,geometry alignment,purity,etc. If not, then you would cap off each gun on the front and only allow the channel you want.
Some projectors have a switch that changes the image from a floor mounted position to a ceiling mount.Others have option pins that you change with jumpers.

Again I would suggest that you try posting on the AVS forum.Bunch of crt projector people who are very knowlegeable and someone may very well know your projector.

Good luck and let us know how things are progressing. Attach some pictures if you can.

let it run for several hours. sometimes those crt,s will come back not like new but will brighten up. steve

Lol let it run.... I can't really object to that.
As for new CRT's I'm guessing not any CRT will work. I've looked on ebay and found crts but they are never for this particular zenith. Or a zenith at all. Would any electrostatic tube work(And I know they probably won't)
And I will try not to look in it. I've only looked in 3 times for maybe a second or two just to check. I figured it was bad for your eyes. It's pretty much an extra bright tv focused on one spot. No more of that though!

I've posted on AVS and it seems they know how to change bulbs and fiddle with controls more than anything. I've got very few responses that actually led me anywhere but another website.

The yoke switching like some one mentioned, Lucky for me There is a sticker showing 4 ways to hook up about 8 connectors to achieve front floor and rear projection and I can't remember the rest. I'm going to try switching it to Front floor projection though.

And I really, really don't think this projector has any menus on it. The whole things seems to be very analogue.

G2 controls....? Are these controls controling voltages at the pins of the crt?

P.S. I've tried turning some knobs that were labelled for the green gun. I can't get it to go any brighter from any of the obvious controls. After playing with them I always set them back to what they originally were. And I never turn them to extremes.

Yes for the G2 question..

It really is hard to tell from the pictures you've attached, but in the first one,the board in the middle of the picture may have the screen and focus controls, but can't be certain. Each control will effect the individual crt.The green is always in the middle. Can you read any of the names of the controls?

From the picture you have firing onto the wall, it certainly looks like the green and blue guns are weak. If you want, try cutting out of cardboard a circle large enough to cover the face of the lenses.You only need 2 pieces. Then, cover two of the 3 lenses and see how much light you get.It's best to do in a really dark room.That projector uses 7" tubes and aren't very bright to begin with.

If AVS is of no help, you could always go the Curt Palme's web site and shoot him an email regarding the crt's...You'll need the model number of the Zenith you have and he may be able to cross reference it to replacement crt's...to be totally honest, you will most likely be looking at 3,given the fact they all are dim.This will give you an idea as to the costs you're up against. You also may have drive board issues, as has been suggested.

If you find the G2 controls, be cautious.Cranking them up can wipe out a crt.These are the controls that apply specific voltages to the crts.

Forgot to mention.This Zenith probably does not have a menu system.A lot of older projectors used analog pots that you use to set up geometry for each tube.That's why it's important to be able to turn off all light from the tubes except the one you are sizing.You always start with the green gun first and then the other two.Once you have them equal, then you go thru the convergence steps. There will usually be pots for each color and they will have name like hpos,vpos,hsiz,vsiz,skew,bow,lin,etc. See if you can find these anywhere.Typical place for them would be in the rear of the set with the cover removed.They should be all bunched together..so, you may see ghpos,rhpos,bhpos or something like that which would refer to green,red and blue horizontal position..Vpos would be the vertical pos and so on.

That is a very unusual projector, It looks like the crt's are round. And yeah it looks too old to have any digital controls. I wonder if those crt's were made by Zenith at their own plant. My Barco's and Bell&Howell use Clinton Electronics tubes that are rectangular. There is a place in Georgia that can rebuild projector crt's. The name is Video display Corp. in Georgia. I searched their website and most of the Zenith tubes run under $200 for rebuilds.

That is a very unusual projector, It looks like the crt's are round. And yeah it looks too old to have any digital controls. I wonder if those crt's were made by Zenith at their own plant. My Barco's and Bell&Howell use Clinton Electronics tubes that are rectangular. There is a place in Georgia that can rebuild projector crt's. The name is Video display Corp. in Georgia. I searched their website and most of the Zenith tubes run under $200 for rebuilds.


VDC is the one that rebuilds crts.I recall reading about VDC replacement for Electrohome projectors quite a few years ago. This is why I mentioned Curt Palme.He reconditions projectors and sells them and has (or had) a lot of crts that were parted out and he may have some info onth the ones that were used in this Zenith.He has used VDC rebuit tubes.
It would not be,IMO, worth it to buy rebuilt CRTs for this unit because they would cost more than you could probably pay for a decent working projector.These early Zeniths were just so so performers. I'm certain that he could find a Sony VPH-1251/1252 for under $200 these days and it would provide a decent start for someone who want to get their feet wet with CRT projectors.These Sonys use onscreen menu systems to adjust everything.

...

should I really try running this set for a couple hours?

Also would brightness invlove The HV lines? Cause if so I have something to say

should I really try running this set for a couple hours?

Also would brightness invlove The HV lines? Cause if so I have something to say
Is it shorted? or arcing? yeah that could make a difference. What's happening with them? Logan

I have that SAME exact projector. Except it is labeled as VIP Mark 3 from layfayette.

I NEEEEEED to find a schematic on this thing somewhere.

The convergence board in these bad boys are poor. I was going to rewire the set with a digital convergence module, but i need to find a schematic.

Oh BTW, its a rare one, and yeap mine still plays. except the poor convergence that just wont correct very well.
Edit/Delete Message

Yes i know this projector inside and out. I'm the person to talk to about this projector. Its a very crappy design, and an extremely rare projector. Although they will play forever if you take care of them.

Your case is probably a open resistor in the feedback circuit off the splitter assembly, and the splitter assembly also known to go bad. (i had to unpot and rewind mine, as i never found a suitable replacement. and i WILL NOT DO THIS AGAIN. it was terrible).

The orientation and convergence setup is done on that little board in the middle of the unit. I am going to warn you that the convergence is piss poor on these particular projectors, and they are video grade only.

I was going to re-wire mine to use digital convergence, but I cannot find schematics/data on this particular set.

Also, the CRTs are round, and the glycol chamber is part of the tube. on mine, the blue tube glass cracked, (CRT is fine, still works) and the glycal leaked out. I had to get a new peice of glass cut for the chamber, dig out the silicon, and replace the fluid and redo the silicon seal.

One more thing: Your going to have to go through every capacitor in that set. I advise getting an ESR meter and adding that to your collection of electronics testing gear. it pays for itself in notime.

Ok, a set this old, the elecrolytics are going to dry up. I had to recap my entire video signal board before mine would even show a picture!. then while i was in there, i went ahead and did up the power supply and HV sweep modules. I found the picture framer board quite annoying, so i unhooked it.

I guess I am lucky, but all 3 CRTs are very strong in mine. Although, the red CRT appears to show a "raster with retrace" even with the filiments unlit and disconnected. and also some purplish blue is seen on the clear spot of the neck, so its probably getting gassy, however once the tube filiments heat up, picture is nice strong and crisp, so it does have some life left.

also its intriguing to know that theres another individual out there with this projector. ive been fighting a monologues battle with mine. hehe.

Well, that looks like the right kind of challenge for you JesusJones! Good luck...

If those are liquid cooled tubes could there be mold or fungus growing in the coolant? I know that was a problem with some rear projection sets. It would cause a major loss in brightness for that tube. The solution was to empty the coolant, then clean the front of the tube and the lens, then replace the coolant with new fluid.
By the way when you search for the tubes try searching for PRT's as well as CRT's. This was to distinguish them from regular picture tubes.

Bill R

Rudy...while I really applaud your intentions to get this projector to work, I am of the opinion that if you are able to get this working,the actual performance will probably be disapointing. Do not take my statement as a negative one..it's just from personal experience..they do not look very good (sorry mbates).

If your interest is just to find the problems and get it working, then more power to you.It would be a great learning experience. But, if you plan to use it for the purpose of watching a large image, you can do much better that this.

If you haven't checked out Videogon, give it a look..lot's of CRT projectors for very little money ( excluding shipping charges if that applies).

Here's an example of a fairly decent projector capable of higher scan rates than a video only projector.That means it can handle line doublers, progressive scan DVD,etc. where the one you have can only do video at 480i which means you'll see the scan line structure big time. Conversly,with one that scans at 31khz, you could play a progressive scan DVD player without seeing those lines...


http://cgi.videogon.com/cgi-bin/cl.pl?projcrta&1228780851&class&3&4&

well if you got fungus growing in those tubes, all power to ya trying to change it. youll have to cut the CRT away from the manafold to even clean it out. it has a drain screw, but you still have to wash out the CRT.

Thank you every one.

And yes after I found out this projector was made in the first year Zenith began making these. I knew it would not be very great, but I thought it would just be fun to toy with. And if it did work half as well as I thought for 10$ it woulda been a steal.

I'm gonna check for mold. Mold would be a god send. (easy inexpensive fix)

Mbates14 You mentioned the splitter assembly. What part is this more specifically?

And I have seen "One" schematic for this projector, but you had to buy it. Other than that I have looked and looked(You probably have to) And it's impossible to find.
This is the page http://www.analogalley.com/m_zenith.htm
I didn't wanna pay for it. Just so i could be sent the wrong one.

And the HV goes to a splitter. Here at the splitter are some controls. (For each tube.)
From playing with them I have noticed they make the color brighter or dimmer.
There is Low medium and High jumper and then a vari pot to fine tune.
Blue and Red were set to medium. And green was set at high when I opened it.
This leads me to beleive the tube was most likely cranked up higher and higher till death(Shucks) (Or maybe there was just more and more mold!)
Also upon starting the unit during the nite I Noticed HV arcing to the frame.It was not intense and stopped after a second or two. But maybe this is a sign of something?

Oh and I got the picture right side up by changing the yoke pin connections. Now it's rightside up. No miracles there

Rudy

Well if you look down the lense while on, or taking a flashlight to it, it will be pretty evident.

I would take the 4 screws out of the lense from the manafold, and take a look that way. there we ill be a "gell like" substance on the face of the CRT glass manafold. its nothing to worry about, just a moisture sealant.


this way you can inspect the CRTs phosphor condition, along wiht fungus, etc etc.

if there is extreme fungus, its not a godsend. its harder than you think. you have to cut away all the silicon between the CRT and manafold to change the fluid. as IT IS all in one CRT, meant to be replaced as a whole assembly.

I dont even use mine anymore, it worked when i last put it up, I wanted to find something different, but i never could around my part of the globe. hehe. (im in cincinatti area).

and, oh yea. if you have to take the CRT apart, careful not to loose the plastic seats that fit between the glass and metal manafold, it holds the CRT a certain position away from the face of the glass.

Yea I'm in winnipeg Canada. Things here are hard to find and generally not cheap.
Garage sales are always the best bet for me.

You mentioned the splitter circuit if the gel was not full of mold?

The esr meter tests capacitor leakage or what? I looked it up only briefly. I might go buy one right now if it's that good

The schematic you want on the page has PV800P as the service #

And I don't think it's mold. Every crt through the lense looks the same. A nice grey colour. With red showing the most wear actually.

yea but if your HV is staying up, your splitter is fine.

I honestly think you need to get to all your capacitors.

Dick Smith ESR meter. you can get the kit, or buy the meter outright.

Ok I bought the new blue one. Looks kinda shabby compared to the black one but that's ok.

I think I paid only 70 or 80$ for it. Sound right to you?

yea thats around that price.

those tubes did not have coolant for cooling. there is a gel pad between the crt face and lens. thats not your problem.

yes it does. I can prove that to you.

there is a gel pad between the glass and lense, but there is fluid between the face of CRT and glass. Crack the glass by accident one time, youll see.

I dug through my Zenith service manuals last night. They are a real mess, I need to organize them. I found a number of projector manuals from the 80s but I don't know if any of them are right. There are several dated in the later 80s and one undated one that looks pretty early.

PV800P
It was also called a monitor
And the year was 85. And there were two inputs audio video and one output for video.

Also the 810 and 820 models were the same as the 800. Just different casing

If that at all helps narrowing down a schemtic or something close

Curt Palme is a Hero.....He said he has a nice new green tube for me that hes willing to send over for a very reasonable price.
I wanna take it...think I should?
Mbates? I trust your judgement on this. You say this projector is reliable. And I am going to test the electrolytics and replace them if necessary? You think tubes would be worth it?

Theres also the issue about the gel that is apparently not reusable. But you said you've done something like this? Is it doable?

...

Ya Know for 10$ I wasn't expecting it to be HDTV that could project on the side of a building. I knew it would be like a normal CRT tv at best.

And just from watching the red on the wall completely unadjusted and a lit room. I have no doubt this projector will suit my needs.(Play nintendo haha)

And I have a question for you Mbates14.
The power supply on your unit. Is it normally quiet?
Mine is making a ticking/buzzing sound. And also after a short run time the large resistors will already have considerable heat on them. Could a bad cap in the power supply cause any type of noises?

And would a weak power supply maybe explain why the tubes seem weak.

I've thought it over and no one could have possibly watched this unit till the green was as weak as it is showing right now. Maybe they put it aside due to failure of something else? Like the power supply?


Woah hoah hoah

After remembering the unit was mounted upside down. Suddenly all these brown burn looking marks made sense. On the raster regulator there are 9 vari pots.
The 3 on the bottom were seized. And under each one it was charred brown. Before this made no sense to me. These burns appeared to start from nowhere and end nowhere so I disregarded them. But now it makes sense. Because the heat and smoke was traveling the opposite way I thought. So I have some cooked pots I think. Mbates14 is there were you had to rewind the pots? by chance


Actually(after another quick check) this vari pot idea makes way to much sense. Of the three that are cooked, RED(my only well working color) can still turn.
Blue and Green Vari pots for this adjustment were seized and the plastic knobs snapped off.(With little effort) This finding just makes too much sense.
Anybody else have thoughts?
Thanks for your time
Rudy

nope my projector runs quiet as all get out. your ticking/buzzing seems like dried electrolytics to me. like is said, everything is a moot point right now, until you go through all the electrolytics. Think of a 1950s tube type. try troubleshooting that without going through the caps first. hehe.

if he offers the tube, by all means GRAB IT. just in case. And my projector looks ok at a flat white sheet :-)

oh BTW that board your talking about, in the middle, is the passive convergence board. if theres any burns or shorts in there, you WILL have to repair this board, as your picture wont be right until you do. and if your pots look burned or otherwise open/bad. that most likely your problem this whole time. unfortunately, youll have to have a schematic to know the ratings of all the pots, assuming they are not marked. which they might be.

Repair this board FIRST. your ticking/buzzing could be comming from that, although unlikely. After this board is repared, the projector might work ok.

Dang... After using a screwdriver to free the pots. I worked with them until I got the same readings as the red pot on my ohm meter. I tested the unit again and no miracles happened.

The green does turn on and play. But it is only visible if you look right inside the tube. (Which I don't do anymore)
It plays the picture and looks OK. It's just dim.

yea if this is the case, and your red is strong, you can rule out the HV.

I would move the RED neck board over to green to see if your green comes back. if not, you DO have a bad CRT. but before you rule this, i would move the red neck board over to green as i said, and move all the yoke connections from the red to the green and vice versa. so your red tube will have green info, and your green tube will have red info.

if nothign changes, (except color) your CRTs are indeed shot.

If i could find a nice replacement projector for a decent price around my area, i would consider stripping this one and sending you the CRTs and parts. as it works perfectly.

Heres some pics of the picture as of now

P.S. The camera makes it seem alot worse...and I also only moved the projector till it seemed more or less in focus and it's on a wall.

I think a white screen would do wonders

The switching idea is hard to do. I wanted to before but I couldn't get it done as simply as is sounded. Things just dont move that far freely.
Also
Could changing just the connectors work? Or would this cause damage?

yeap thats a classic sign of wasted CRTs. They are toast.

Ok, heres what we are going to do. If you can figure out a way to get it from point A to point B without too much effort from me, you can have mine. I got LCD so it dont bother me anymore, and i havent turned mine on in 3 years. it did work. although the blue CRT, you need to get a new glass cut for the front (where the old one was broke, and fluid got everywhere). then RTV Sealed back in place, and CRT remounted and re-siliconed. the CRT still works perfectly fine as it is, theres just no coolant for it. and you can use one of your old dead CRTs as a pattern. or better yet, you could cut the silicone away from your dead CRT, and stick the good blue CRT in place, and not have to get anything cut for it. possibilities are endless here.

Also i lost all the covers and several screws and feet to mine during the move 3 years ago. so its just a metal frame and chassis. the unit like i said still works, so you might be able to take 2 and make one work. and have lots of parts.

Let me know.

Yes I noticed these Crts and very browned..... More browned than ant crt I've ever seen.

So maybe they are just toast like you said..Having yours would be great! But the point A to point B problem.
Where abouts do you live?

im in the cincinatti area. in USA. ohio.

I did a shipping estimate

For a 130 pound
30 inch wide
30 inch long
and 20 inch high

It would cost 100$ for shipping. But I think in reality it's a bit lighter and smaller so perhaps a bit less. Mbates are you sure you'd be willing to give yours up?

I also think when it costs 100$ UPS guarantees your packages safe arrival.

Can anyone think of a possibly cheaper way?(Just wondering)

What do you think mbates?

P.S. If we did do this, the box couldn't be any bigger than 33 or 34 inches in any way. Or else the price sky rockets.

I dont have any boxes that big. hehe. yea i dont use this goofy thing, everything that I got now is all HD. but ive been on the lookout of a good VGA/Data grade CRT projector.

I could strip out everything liek the boards and stuff, and do it this way. But ive never packed CRTs before, so i dont know how safe they would be in shipping.

A box with foam inserts all around. And then once the crt is in the middle pack it full of loose packing foam.(And the box has to be just the right size to fit it. This should work rather well. Any extra insulation after is even better.

And yes if you could strip all the parts out and exclude the frame this would make shipping less costly and you would not need a larger box.
If you are willing to do so. I think it would be a great idea.
And it would be much appreciated :)

Only thing is shipping all parts individually
I estimate dthe price of one CRT
10 pounds 5x5x12 inches
22$
Plus 2 more 66
plus boards probably 80-95$ just like shipping the whole thing.
On the other hand stripping it. And fitting it into one box. Whole different story

If you could fit it all into a box 25x25x25 or smaller
And it weighed somewhere around 80 pounds it would only cost 80$ although it may come out to a bit more.

Also (just wondering) You can tell just from those pictures that my crts are shot....?? And you think the projector is working OK otherwise?
And normally would red be the last color to stay strong??(Just wondering)
And I've looked at the CRT's to look for wear. There is light browning on the face. But it is not as bad as some shots I have seen on the web.

Alright well. I turned on the projector with no source hooked up today. I waited and the blue tube turned on.
This confused me. The CRT's never turned on when I first got powered up with no source hooked up.
Then I remembered. MY POWER SUPPLY. I changed one 680 uf cap in it. That's all. After that I hooked up my dvd player and it worked. But I thought to myself that it was only because I actually had a source hooked up to it. But now I think it may be the cap I changed.
And my power supply makes strange noises as of right now. I am going to see what other caps I can change on this board today with my supplies.
Any thoughts on a weak power supply causing loss of brightness???

well lets see. like i said before, get an ESR meter and go through all your caps. every single one of them.

and what concerns me is not even a hint of green. but if you want to know if your green tube is bad or not, your going to have to make an effort to do so. such as "stretch and reroute" those wires. Ive done it on this projector, and i know you can too. Like i said previously, My projector makes no noise, other than the normal whine of the sweep circuits, like you would hear in any TV. Any other noise is considered NOT normal and should be looked at seriously.

I got my projector when i was your age, and i was your age back in 2003. But ive come to learn alot with electronics since then. (i hold a degree in electronics engineering, though unemployed).

Before you go chasing around yourself in a gutter like a chicken with its head cut off. Your going to have to pull each board individually. I would start with the power supply. Then i would start with the sweep, I would then inspect the passive convergence module in the center of the unit. Then i would move on the video process board, which is the board to your right if your facing the projector with lenses in front. You could be missing a green drive, and have a corrupted blue drive. possibilites are endless here. youll have to go through each one individually and rule it out on a checklist. This is all basic troubleshooting.

When i mean pull these boards, I mean look at the underside for obviousness. Bad solder, ESR test all electrolytics, etc etc etc. Even might go as far as reading out all the resistors, and do a static check of each transistor and diode. Once you deemed the board is good, place it back into the unit. and check the next one. Also the CRT neck connection boards, dont rule these out either. zenith is known to have resistors change in value, and open on these boards, that supply critical voltages to the CRT guns. THIS IS WHY you need to swap places with CRTs to rule out the CRT and save you some headache. IF electronics is something your going to get into, your going to HAVE to learn these things, and learn to do them. (and correctly btw, ive got scars from my mistakes as a kid).

This is pretty much all i have to say at this point. When you decide to start putting some strong effort into doing these things, then let me know, and i can help you further in your endeavor.

My method of trying to figure shit out, and your parents may think your nuts if you try this, but I always pace back and forth in the room talking to myself, as if i was explaining something to another person. and when i do this, i usually catch shit that i forgot about, or overlooked. and then from there, i can figure things out.

History on my projector:

My projector was a VIP Mark 3 from lafayette. rebranded PV800 basically.

The projector came from my local school district, badly battered and abused from students. the blue CRT glass was cracked, and fluid all over the bottom of the unit and tube. some of the fluid got into the HV wires and caused an arc, which shorted out the Horizontal output transistor, or HOT.

So, yea i wasnt much off from you. hehe. first, i had to remove the gell in front of the cracked glass, and then take the blue CRT away from the metal manafold, which called for cutting off the silicone holding it into place. i then extracted the CRT, cleaned out the fluid, removed the glass and the RTV that held it into place. i never replaced the glass and fluid, i just stuck the CRT back into place once the mess was cleaned up. I proceeded to replacing the HOT. The set would fire up, and shut right back down. and this was due to a failed HV splitter off the flyback. I had to remove all the epoxy, which was NOT fun at ALL.. in the least bit. and i found the short in the windings. i rewound just that portion of the block, and dumped some 5 minute epoxy back into the block. seveal tubes of it. hehe. Then, the set fired up and worked perfectly fine. and has played since this day, and i ended up finding another splitter, so i just replaced it.

Ok I thought about the crt neck board switching last night and figured out a way to do it.
Then I went to sleep and forgot all about it hehe.

Now I'm almost half way through and need to know one thing.
AT the top of these boards connecting to the white socket part are two larger wires.
I thought these might be heater lines BUT
One of the ends of the wire goes to the HV splitter
Then the video board
The other to ground.

Could still be for the heaters I don't know.
I ask because This is the one part that is proving to be difficult in moving. And if it is for heater's It's not exactly necessary to move it. Is it?

any lines going to the splitter assy are focus/G2 lines.

Alright do I also need to switch the HV lines around?

Other than this it is ready to fire up.
And wild i had the board out I measured all resistances on it. They all check in OK. And the caps aren't open either.

not for testing perposes no, all you need to do is swap the necboards, but leaving the original plugs in place. (so red gets green, green gets red).

if the problem shifts, your missing a votlage, most likely from an open resistor in the neck board.

PVR4663 Zeniths were bad for this.

Alright gimmi 5 minutes to tell you what happens

Okay So I'm pretty sure I did this right and....The green did not come back on. It was the same brightness and the red wasn't exactly as bright as before but that's about it.

The green stayed the same I'd say

So my tube IS dead then?

Also the red and blue are acting up now Wont keep a still image

I know nothing about your unit; but, I recently had an RCA big screen with a dim, blurry red screen. The problem was the focus and G2 block that contains the adjustment pots.

well if you swapped the neck boards and yoke connections, BUT you left teh connections on the neck boards the same (meaning not swap them). and it stayed the same, i woudl say yes you have a dud tube.

youll have to elaborate on "keeping a still image"

like is said your going to have to go through all the caps. then look at the CRTs.

My input image had a bit of audio in it......don't ask how but that was the problem.

And yea I'm done with it for now. My ESR meter should arrive Monday or Tuesday hopefully and we'll continue on from there.

Would it be typical for a dud tube to show very faint picture. But nowhere near viewing brightness

Thanks for the help so far
Rudy

I am gonna do a full check on the G2 board on my unit. I have suspected it from the start but it looked very OK
I suspected it because the green control had been switched to high Unlike the other two.

I checked all resistors on my board and they are fine.
The pot for green also checks in the same as the rest. My problem does not lie there

Also I've heard before that Zeniths safety caps will fail. There is a safety cap in the power supply right by where the noise is coming from.
I'm just wondering if these caps had a specific value. The value is not printed on these particular capacitors in my unit. There is some writing though(letters and stuff)
Just wondering...
Rudy

My input image had a bit of audio in it......don't ask how but that was the problem.

And yea I'm done with it for now. My ESR meter should arrive Monday or Tuesday hopefully and we'll continue on from there.

Would it be typical for a dud tube to show very faint picture. But nowhere near viewing brightness

Thanks for the help so far
Rudy

Yes, it's possible for a bad CRT to show a dim, dull picture. CRT's usually die a slow death. The picture will generally get dimmer and dimmer and fuzzier and fuzzier until there's next to nothing left.

If you are going to work on TV's, it will pay you to obtain a decent CRT tester / rejuvenator. Something like a B&K 467 or higher model number should suit your needs. They cost several hundred $ new; but, can often be purchased for a little of nothing now since the CRT is not quite as popular as it once was. There are many test sockets available for these B&K testers that will allow them to test most CRT's. You can also rejuvenate weak CRT's with these testers. Rejuvenation is not a permanent repair; but, it will buy you some time and let you see the condition of the rest of the chassis. I've had rejuvenated tubes die in minutes and I've had others that were still going a year later. Try to stay away from the '70's and older testers. The rejuvenate functions on these older models often does more harm than good and sockets are not easily available for the later tubes.

Use the link at the bottom to veiw this properly.


I have no comments one way or another with respect to this device. Please contact the author for further information.

(From: Mario Di Stefano ([email protected]).)

Here is the 'gadget' I use to rejuvenate 'tired' CRT's:

T1
o---+--------+ +------------------------------->
| )||(
M | )||(
A | )||( 6.3 or 12 Vac To Filament
I | )||( Secondary CRT Tube
N | )||( (no Polarity)
S | )||(
| )||(
o---|-----+--+ +------------------------------->
| |
| ----------------------------------------> CRT Cathode
|
| +-----+ _|_
-------------------| LP1 |-----o o------------> CRT 1st Grid
+-----+ P1


Where:

* T1 is a standard mains AC transformer.
* LP1 is a standard FILAMENT LAMP (60 - 100 W) working voltage according to mains.
* P1 Hand Pushbutton.

Other things needed (not shown):

* Mains switch (best if with overload protection or with fuse)
* 4 ISOLATED clips like the ones used in electronics to make contacts with the pins of ICs. These isolated clips ARE IMPORTANT. You don't have to touch any connection during the cleaning.

I think this circuit works better if the mains voltage is 220 Vac.

How to use it:

First we have an tired CRT (BW or colour is the same). We have poor image contrast, 'strange' brightness, also strange colours. Next we have to remove (if present) the CRT socket to its circuitry (beware to disconnect mains voltage FIRST!!!!!). At this point could be useful to discharge the HV using an isolated wire FIRST connected to CRT grey body and then to the make the contact UNDER the suction gummy which carries EHT. to the tube. It is not a dangerous voltage, but could be better not to discharge it over the body!

Now we have to identify the filament pins. Usually on the schematic circuitry of the Monitor/TV it is clearly written. If the schematic is not available, using an ohmmeter we should find the two contacts which gives a few ohms. These contacts usually are put aside each other) have to be connected to the transformer secondary of the circuit above. The Cathode and 1st grids can be found looking very closely into the tube glass (use lens and good light if necessary). Keep in mind the way the CRT electron sources are built. These usually follows this:

Cathode
| (B/W CRT tube)
V
O------+ | |
+ | | <- 1st Grid
Filament + | |
+ |**| <-Spark (read text below)
O------+ | |
| |
| |
Cathode O---------+ |
Connection |
|
1st Grid O------------+ (Damn'd ASCII graphics!)
Connection


Try to connect and turn on the transformer. The Filament in the CRT should turn on in a not-so-bright red (if it is a colour tube, we have 3 filaments on).

Now turn off the transformer again. Connect the Cathode wire to the cathode pin of the CRT Tube. Connect the 1st grid accordingly.

Turn on the transformer. FIRE button P1. If there is dust (due to aging) between the cathode and 1st grid, the circuit will blow-up it. If this happens, you could (but not always) even see the LP1 turn on and off randomly (a good cleaning gives a lamp OFF) and some sparks inside the tube. The tube collar glass now becomes hot: it is normal. You can even 'force' better sparks if you 'ting' your finger against the CRT glass (not so strong, of course). If it is a Colour CRT, you have 3 Cathodes, 3 1st grids a anyway 1 filament. Useless to say that the procedure have to be carried out for all these electrodes. A good cleaning, gives a LP1 steady OFF. If it is a steady bright or dim, means that a 'bridge' has been formed between the electrodes and there is no way to recover the tube. Turn off the mains, remove the connections, and re-apply the original socket. That's all. I'm not tired to say: BEWARE OF THE MAINS VOLTAGE: IT CAN KILL!! If you are not so skilled, don't try to do this procedure. I used this circuit lots of times. It worked almost anyway. I recovered lot of thrown away PC monitors, and now are working well....


Borrowed from http://www.repairfaq.org/sam/crtfaq.htm#crtwir



It pretty much uses a light bulb connected to the mains to BLAST dust off from the cathode and first grid.
I don't much see the need for the heaters to be on but apparently that's how he does it



Worth a shot?

You'd be better to get a real tester so you can read the condition of the tube on the meter. You don't want to rejuv a good tube! You'll actually make it worse and/or decrease it's life. Rejuvenation not only removes the trash; it removes some of the cathode coating that emits electrons. On a good tube; there is obviously minimal gunk on the cathode. Rejuvenating such a tube will remove the material that emits electrons from the cathode. You can probably pick up a quality tester on epay for $50 or less if you play your cards right.

Alright I wont mess with it then.
And can I try changing the red and green or blue and green HV lines around.
I just want to try it out. But want to know if it will have any Bad effects
Thanks
Rudy

Today my ESR meter came. After spending 2 hours putting it together I was very happy to see it work properly when I turned it on:yes:

So I got right to work on the power supply.

All electrolytics are fine.(Suprisingly...Gonna switch em anyways)
The only capacitor which did nothing on the esr meter. Was that safety cap I mentioned before.

It is green and larger. Looks like a dipped radial cap. You guys know.

The only thing it says is:
Crit Safety Comp
(s) 22-7672-10 8441

I doubt that means anything other than a model # but maybe it helps.
Any idea as to what one of these safety caps would be rated .1 uf, .01uf 1000volts?

Thanks Rudy

you sure your reading that meter right? i dont think they are all going to be perfect. and it would take longer than a couple hours to go through all the electrolytics in that set. hehe.

I don't think you have to worry about that green safety cap. They were used in most '80's Zenith TV's and I've never seen one fail. And, I've worked on many '80's Zenith's.

haha Oh no not all of them.

I went at the power supply first because I know there was that strange sound in there.

And I dono if i'm just getting used to it or what. But I could be wrong I'll go double check again soon.

But the safety cap just showed an open short. No connection at all. Unless its really small. Like .02 or smaller. It should say something.

haha Oh no not all of them.

I went at the power supply first because I know there was that strange sound in there.

And I dono if i'm just getting used to it or what. But I could be wrong I'll go double check again soon.

But the safety cap just showed an open short. No connection at all. Unless its really small. Like .02 or smaller. It should say something.

And I checked capacitors again IN ONLY THE POWER SUPPLY
They all check in .25 and smaller Which is correct I think. And none vary greatley from the other similar values. What would a dead cap come in at...Say 470 uf?

Sorry about the double post
Damned Internet!

That safety cap is probably rated in the .0039 to .0068 range.

Ok I will leave it alone then.

And as I was pulling boards and checking them I noticed a board that had two cables switched and in the wrong spots. The letters on the connecters clearly did not match the baords. Should I look further into this? Try switching it?

I also followed the wires. The connecters are connected to the board with sharpness, brightness, balck level and all that stuff.(AT this board they are in the correctly labelled spots) Then they go to the board at the right side of the projector facing the lenses. This board then goes to the video boards on the crt necks. Mbates you should know what this is. Any advice?


Thanks
Rudy

Mbates does your projector have a 3 prong plug or two?? The noise in the power supply gets quieter when I touch the ground/frame.

Also the noise got quieter after changing some caps on another baord. I think I"m getting used to the ESR meter. And I love not having to take things out to give a good test.

So I just wanna throw this out there again.
The green tube in my mind is weak/dead
When I originally got the unit the green focus/HV was CRANKED up.
I have tried switching the CRT neck boards, so that the green tube gets all red info and the red gets all green info.

The red still worked and the green did not change.

I mentioned before a way to try and rejeuv this tube using a lightbulb and mains voltage.Any thoughts on this?

The only thing that I have not tried changing for this tube is the HV line.
All three CRTs have HV lines Going to what I call the HV splitter. They are easy to pull and switch. Should I try switching these around??

Any one have any suggestions? Should I try a rejeuv or something like that? Any thoughts?



Thanks for your time
Rudy

P.S. I noticed in the HV transformer there was a cap type deally. It screwed off and inside there was nothing. I shined a light in and noticed a spring at the bottom. The only thing I think this could be for, was a fuse. And there definatley wasn't one inside. Any one know what this might be?

Happy nBirthday to me"

Happy Birthday to me

HAPPY Birthday too meee

Happy Birthday to me!

yea those are quick connects for the HV wires and stuff. My unit is a 3-prong power plug.

Alright so I've tried everything to get that green tube shining brightly(HV line switching, CRT neck board switching) But nothing helps.

So I'm going to try leaving the set running for a couple hours.
I've heard this sometimes brings a tube back...?

Also, Mbates14, does the ground from your plug go to ground(chassis)? Or to the power supply circuit board?? (if you know off hand)

Thanks
Rudy

I have to dig it out. its burried under boxes and other crap for the last 3 years.

Alright well I have changed just about every cap on this set that has a strange/high esr reading. The power supply has also been totally recapped.

The noise in the power supply still exists. I've noticed it only starts up when you apply an actual video signal to the projector. Then the power supply starts it's buzzing.

I've also noticed that the power supply shuts up when you put your hand on the frame. I've considered putting a ground wire to the frame. Good idea??

Theres one more cap I am going to change. It's a small one but the only other one I can remember giving any sort of bad reading. After this I will run the set for 3 hours.
The only reason I havn't already is because of the power supply noise and how quickly some of those resistors in the power supply get HOT.

If anyone could tell me there thoughts here. Should I put a Ground to the frame? Is the power supply acting more or less normal? Should I go for the 3 hour test?

Any thoughts would be much appreciated. Or else I"m just gonna continue on with my plans and hopefully not destroy the thing..

If you think it's a good idea wish me luck
Thanks
Rudy

ground on the frame is typically a good idea anyway.

Thanks Mbates

After some studying I went ahead and put in a new chord with ground and attached the ground to the power supply.

It was quieter but didn't work any better.

I let the set run for a while. And the green didn't brighten up any by the end. Maybe just slightly but enough to make a veiwable difference.

So I wanna try and give the green some new life. Just to see if it works...have some fun.

I have 3 ideas. But do not know witch is the best way to go about it.

Idea #1
Bump up the heater voltage temporarily untill the tube begins to work better. Then return it to normal.

Idea #2
With the heater ON. Charge up a Capacitor. And zap g2 and cathode pins.
(1 uf cap starting with about 100 volts)

Idea #3
With heaters ON. Use a light bulb to do the same thing as the capacitor.

Tell me what you think works best. And I will try it out. I have nothin to lose at this point.
Thanks for your time.
Rudy

I have increased the heater voltage to bring back old tubes, especially ones that had not been used in years. The normal filament voltage is 6.3. I usually use around 8 volts. Most TV parts suppliers sell brightners that can be soldered between the filament winding of the flyback and the CRT filament that will boost the filament voltage.

Before you buy a brightner, connect an 8 volt source to the filament and let it cook for a half hour or so. Then, remove the power source and connect the CRT for normal operation and see if it looks better.

Ok so your saying to just let it cook with no image showing or anything??

I've never done this and I wanna do this properly so help me out here with the fine details just a bit. Please.:yes:
So let me know witch of these two mothods is correct....


#1
Hook up an 8 volt source.
then just let it "cook"

Or

#2
Turn the unit on with the heater supply changed to 8 volts. And see if the image warms up?
If I do #2 I'm pretty sure all 3 heaters are hooked up in paralel to the voltage source.
So if I disconnect one heater. And leave the other 2 running. Will there voltage go up because of the drop of current, or is there a voltage regulator most likely?

Thanks for helping me out
Rudy

Just disconnect the CRT board and connect an 8 volt source to the filament pins. Leave the set off and let it cook for 30 minutes or so. Then, remove the 8 V source, reconnect the CRT board, and see if the green tube is brighter.

ahhh Thanks very much
I will do this and report back later
Rudy

Idea #4. Replace the CRT.

Take a flashlight and look at the end of the tube. youll see the filimetns going up into the cathode. if the cathode is very discolored from white, the CRT is deemed shot and needs replaced.

yea yea yea new tube I know. Easier to say than do

I'm just havin some fun with what I got.
If anyone wants to join in on the fun. Well then....

Should I ZAP it with a cap
Or Zap it with a light bulb???

Thanks
Rudy

P.S. I did the heater "cooking"
I set up a half wave rect and got 7.2-7.3 volts on the heaters. For about 25 minutes.
I tested it after and it seemed a little bit brighter.
Should I bump the voltage to 8 and try again. Or move on two some more brutal stuff.....

And I have a new tube coming but I may destroy the gel coolant when I put it in. SO I'm more than happy to do whatever to the tube already in there.

000

There may be this resistor. But each crt neck does not have it's own resistor.

All three crts heaters are paralelled then connect to the Hv sweep board. On that board there is most likely a resistor that if bypassed would bump up the voltage. But it would do so to each crt. Causing the two better tubes to get worse alot faster.

I wanted to try powering the green crt with my homemade heater supply and then turning the projector on.
But running the other two crts would draw less current. Possibly bumping the other two tubes heater voltages much tooo high. Unless it is regulated??

As for old Tv's I do like them. But cannot store anymore than what I already have, and I only find TV's and other things in the garbage or at Garage sales. And since it's finally snowing today. I doubt I'll be picking anything new up till next year. So a CRT tester for me at this point would not be a very wise investment.
Rudy

CRT testers will probably get even cheaper by next year. I will agree that if you plan to fix TV's, it would be well worth you buying one. I can't tell you how many TV's I've brought back to life by rejuvenating the CRT. These sets would have otherwise gone to the trash heap.

Ok I have read about this a fair bit.

I plan on using a 250 volt source and a 5 K resistor to make a 50 ma surge across the cathode.

Apparently 40 ma is the lowest used and it goes all the way up to 110 ma.

Two, Three second burts of this should do some sort of trick.

Sound good?

Ok i tried blasting it using the 250 volt power supply.. Heres how things went.

I hooked up the cathode and G2 when I did this.

I used my ammeter to veiw current and well...

Not much happened...The tube took the 30 ma. There was no purple glowing in the crt neck or anything. I gave it a couple shots of this then set it back up.

The green was still the same

I tried again! This time with only 2 k inbetween. Should have been nearly .125 amps. Current reached maybe 50 on my meter and that ended that.

The green is still the same no better or worse.

Anyone have some suggestions
thanks
Rudy

D'oh!

I shocked the wrong pin! I'll be back when I get the real results

Tried shocking what definatley must have been G2 an no current flowed at all. I'm confused to say the least...
Also how can I tell witch pin is wich. I know you actually have to look at where the wires go but I am not to familiar with what and where all the parts are.

_____
____ |
| x | |
| x | |
| x | |

Not that my picture makes much sense but here it goes....The xxx's are the heater. The iner cyclinder Which I cannot see (I assume it's there) Is what I am using as cathode(A fine wire goes between the larger outer shell and the heater wires). And the large outer shell I was using as G2. Sound right?

P.S. The picture is drawn with the left side cut off so it would be easier to draw.

Thanks
Rudy

Oh by the way

THE GREEN IS WORKING
IT"S WORKING
IT'S WORKING

HA!

very kool

I am happy with you.

I'm glad you got it working. Just be aware that rejuvenation is a "hit or a miss". It may run for a year or more; or, it may crap out tomorrow. At least you know for sure that the tube was the problem and you can buy some time before having to replace that tube.

He he I have the tube on the way already.
And thank you very much. I am Proud of myself.

I just really wanted to make sure it wasn't an internal problem. And now that all is well I can start to try and figure out why the red is way off too the left..hehe more fun for me.

Thanks a bunch folks
Rudy

now dress her up real nice and lets see some pix of this thing in action:thmbsp:

I added a picture. But it's pretty poor the camera didn't wanna make it seem as bright as it really is and I couldn't figure it out before the batts died.

P.S. This picture is waaay out of focus(The projector is out of focus). And it's on a green wall.

From this picture you can see that the colours are still rather off. And that there is a dominent red throughout the whole picture. Kinda pinkish.
I've fidled with tone controls and all that but just can't get the right mix.

Probably because all three crt guns vary in intensity. With red being the strongest.

And thats Mario Bros 3 Your looking at. Easily the greatest game ever created.


And if any one here knows. What is the general set up procedure for one of these?

And mbates14 a more specific question.
My projector is set up for front floor projection, roughly how far should it be from the wall???

In the picture the projector was moved pretty far back so I could line up the red with the other colours. The red seems to stay off to the left. If it is too close to the wall. But when it's closer the focus seems better.

Sorry for the jumbled post. I just have alot to ask and say.
Rudy


P.S. These are new pictures off my cellphone.
You can see that red is bright compared to blue and green
Before you would of seen the green just BARELY from the front. ONLY if you squinted really hard (just kidding but you know what I mean)

This image is also nearly 7x7 to 8x8 feet.

Also if anyone wanted to know how I "popped" or w/e the green tube back into working then keep reading.

Alright setting this up is harder than doing it.

I used a simple half wave rectifier conected to a 12v transformer to create a steady 7 volts for the heaters. To adjust your voltage you must vary the capacitor you use in your cicruit. Start small and go higher.

Next up obtain a 200-250 volt power supply. I had one I built in school. Put in inside a old computer power supply and gave it some connectors.
Now depending on what tube(big, small) and power supply voltage you have you must pick a suitible resisitor to allow 40 ma to pass throught the cathode. At 250 volts 6.2k ohms does the trick.
E=IR 250/ .04 = 6.2 roughly.

Now the rest is simple. Find your heater pins on the crt. Now take a 12 guage wire and screw in a screw into the wire to make the rubber stretch so you can easily slide it over pins. And use it as a makeshift connector. Connect the heater circuit. Test it out first. If all goes good. (It glows like it should) Move on..

Take the power supply Hook up the positive end to your g2 or 1st grid. (I used first grid) Then hook up your cathode to a wire, put this wire to your resistor NOW I suggest you hook up an ammetere here. So you can make sure your not destroying things or doing nothing.Then hook it up to the negative on the power supply.

So now you have your heaters running on 7 volts.

And your grid has 200-250 volts +
your cathode is connected to Resistor, ammetere then the negative.

Now let the heaters do there thing for about 30 seconds.
And turn on your supply.
When I did this I let the supply run with the negative out of the supply.
And when I finally got the guts to do it. Plug that negative end into the power supply for roughly 2-3 seconds. Do this twice or three times. The less the better.

Now your ammetere should show slightly less that what you expected it to show.

If the ammetere does nothing. Check to see everything is connected properly. try switching G2 and grid 1.

If it still does nothing. Leave the system I just described on untill current begins to flow. As soon as it does, stop! You've probably fixed it.

Now set it up and test it out.
Don't be discouraged if it doesn't work the first time. I had to try about 4-5 times.
And if the first time doesn't do the trick you probably have to lower the resistor you are using. When I fixed my tube I started with 6.2 k and moved all the way down to 2 k before it made a difference.

Start easy and get rougher. Especially if you have nothing to lose!

Hope this helps some one

Oh and if one time when you connect the negative it makes a rather large spark and noise.(Unlike the other times) Stop and see if it's working.
When my tube finally came back this happened wild I was reviving it. Less is better than more.

P.S. Be careful when you do this. I've played with tube amps so I know how not to shock myself.
Slow and careful is better than speeding when it's snowing trust me I live in Winnipeg

000

hmmmm ever blow out any filaments useing that method Andy?

Sounds like a good way to do it.

000

I had an old Philco 19" delta gun tube that was toast. I had that filament so bright that it looked like a light bulb; but, it never blew. I've seen a few open filaments on B&W tubes; but, never on a color tube. Those filaments are generally very strong.

hmmmm I might just try to do the green tube again.(using your method though)

I really dont think I was very harsh on it. And it's still not bright enough.
Plus I'm just playing with it.

What was the wattage of the bulb Andy?

But first I'm definatley gonna beat super mario bros on it. Just in case it doesn't work after the second try :)

I added a picture. But it's pretty poor the camera didn't wanna make it seem as bright as it really is and I couldn't figure it out before the batts died.

P.S. This picture is waaay out of focus(The projector is out of focus). And it's on a green wall.

From this picture you can see that the colours are still rather off. And that there is a dominent red throughout the whole picture. Kinda pinkish.
I've fidled with tone controls and all that but just can't get the right mix.

Probably because all three crt guns vary in intensity. With red being the strongest.

And thats Mario Bros 3 Your looking at. Easily the greatest game ever created.


And if any one here knows. What is the general set up procedure for one of these?

And mbates14 a more specific question.
My projector is set up for front floor projection, roughly how far should it be from the wall???

In the picture the projector was moved pretty far back so I could line up the red with the other colours. The red seems to stay off to the left. If it is too close to the wall. But when it's closer the focus seems better.

Sorry for the jumbled post. I just have alot to ask and say.
Rudy


P.S. These are new pictures off my cellphone.
You can see that red is bright compared to blue and green
Before you would of seen the green just BARELY from the front. ONLY if you squinted really hard (just kidding but you know what I mean)

This image is also nearly 7x7 to 8x8 feet.

the green is still very very weak. it needs replaced. or invest into a tube rejuvinator.

Alright well to keep people amused. And just to see what rejeuving can do to a projection CRT. I am going to buy a 20watt 240 volt bulb. Witch should come out to 83 ma.
If I can't find one, I might have to buy a 10 watt 120 volt bulb.

I'll do it just like andy said.

My CRT tester applies a voltage between the cathode and G1 with a low wattage 240v light bulb to limit the current. It instructs you to gradually increase the heater voltage to 10v (for a 6.3v tube) and wait until the cathode current reaches about 80mA, and the current limiting lamp lights brightly. Then to interrupt the heater voltage (not the cathode) until the current drops down, and repeat as many as 2-3 times (although I usually only do it once and re-test).

Be back with more results.:thmbsp:
Rudy

So I go the current to go to 75 ma

The green stayed the same I'd say.

But it doesnt matter I got the new one coming very soon.

As for anyone else with a very weak crt on their hands and nothing to lose, I think this is well worth a shot. And you could easily bring a weak TV or oscillscope back to usable condition.

I don't know how long it will last. For me in the couple hours I used it. It did not get any weaker. So I say go for it.

I'll be back with more pictures and news when the new tube gets here.
Rudy

COOOOOL

I got the new green tube! I especially like how it does not look burnt or browned at all :D

So I think that this tube I got has some sort of gel pack in it or something. Cause looking at the screen of the new CRT I could see bubbles floating around. Either way this made me happy because I thought I would have a great deal of trouble with installing this. Due to a gelpack that would be destroyed as I removed the old one. But that still may be true.

I am puting it in soon and will have pictures to share and stories to tell.

Rudy

Super coool

It's been done. It's changed. I managed to reuse the gel pack. I'm sure it must have affected the green slightly but it's hardly noticable if yaknow what I mean.(I don't notice anything)

Other than that IT's working good. (except the convergence but I'll get that sorted out)

Heres some pics
Can you guess witch one is the old one?? Haha



Now I wonder and I'm sure one of you will know.
To make the crts last there longest how should they be running....
Example: Turn G2 up for higher brightness. and leave the actual user adjustable brightness somewhere in the middle.
Or
Turn the brightness way up and leave g2 turned down.???
Any suggestions would be greatley appreciated.


P.S. All pictures are with a sh*^^y cellphone

I have managed to improve picture quality a great amount. I used a convergence test screen. It was hard and took me a GOOD WHILE.
In the end it was not perfect but Much Much better. Playing Super Mario Bros it looks almost high def. Hahahaha But it's definatley not. Cartoons look awsome. And movies are definatley watchable.

As soon as I this thing pointed at a white wall I will post many pictures.

finally some overdue pictures.

This is from the Disney Wall e movie

PLaying on my white wall. With some light in the room.

Watcha think?

Looks pretty nice to me.

new green tube?

well youll never get the convergence perfect on that set. hehe. Well your convergence is a little bit better than mine, and mine wont get any better than it is.

Also my green tube is way more burned in than your green tube, but its nice and strong. But your burn-ins on your blue is standing out pretty well in the corners.

Yes Brand new Green tube. Very nice :)

Is that why its dark on the left edge and
Bright on the right edge...? the blue tube?

My blue seems like it's the next dimmest tube.

But yes on a white screen you can see theres some burning and fading in areas.
I Guess to some one with a good projector, this would not pass as usable for anything. As I've been told by people on the AVS forum.

Nothing to do about the burns as far as I know.
Its the actual phosphor which is burned up right?

Oh well I think it looks great. It was the camera pictures that actually let me see any poor convergence. For cartoons and my games this thing will be awsome.
And I have a dumb idea but it still seems cool in my head. Since this projector cost me maybe 50$.

If I get another one.

I might just mount this thing on top of my car.
I like to get out of the house and usually go for a coffee and watch a episode of something on a laptop. I could just stick it on top. Cover it. Then drive up to any large store. And bingo bango I'm drawing a crowd haha. Not that I'd want a bunch of people standing around my car, but I think it would be cool.

Cheers
Rudy

im impressed! pix look good in my opinion. id definatly be happy using it. Good movie BTW.

Thanks for the comments guys! And yes Wall E is a very good movie. A good eye opener if yaknow what I mean

I tried playing x box 360 on it earlier. Call of Duty 5
Amazingly....you could play. You could read everything on the screen and could see most things.
I actually managed to play through half a level. It was hard to see the bad guys though. But if you've ever played the game you know it's pretty hard to notice them anyways. I was impressed. And for a party this projector is definatley Guitar Hero worthy :P

More pictures!
The video signal is 800x600 pixles.

Yea thats how they are with all versions of CoD.

i just finished CoD5. about 2 times now. working on the third.

Awwww man :(

I turned it on today to watch a movie and the green was on super bright.
There was also a spot in the center that had no green(Looked like a mark on the wall)
There were some diagnol lines to at first. It still shows picture but it is not right.

I thought for a second it might be heater to cathode short :( please tell me its not

I still have some control over the brightness of it but it gets very bright very fast to say the least.

To test for shorts do I have to turn the heaters on first?
Thanks for the help

pics tell 1000 words. better check the CRT face to make sure you didnt burn anything in.

the retrace lines are caused by over-driven G2 voltage, as the CRT isnt going into cutoff during the retrace when its supposed to.

DAMN IT

i have a burn in my phosphor. Causing the black mark
SH*T!
The mark almost looks external but i know it's ruined. I'm just so mad I have no idea how it happened. It looked fine the day before.

The only thing I can think of is the one or two times I shut it off and it did that little dot thing like some TVs used to do. I knew it wasn't normal. I'm not so happy anymore.

you obviously did something to it. you dont just "burn in" for no reason at all.

like i said. pics are worth a 1000 words. POST SOME PICS!!!!!! as i hinted in the other post.

000

Awww man it probably is totally my fault.

When it acted up on me I fidled with the picture and black level settings.
These make teh picture brighter and stuff.
I may of left them cranked up with a black screen. (Which at the time showed green)
Then it probably happened.....I'll never forgive myself. I'll get some pics of the burn.

The burn sorta looks like the black shadow of your cursor(mouse) But inverted.

See how the A is red
It's because the small dot that the screen made at shut off burnt RIGHT THROUGH the phosphor and it no longer lights in that spot.
Its a real bummer its right in teh middle of the screen. But for my original plan which is just to play nintendo on this thing Thats OK I Guess.

I was happier when it didn't have the burn. But I feel much more OK about it now then I did yesterday.
And now I know. Never leave a set that doesnt seem to be working right. WITH ITS BRIGHTNESS CRANKED!!:thumbsdn:

P.S. This is a wiked game for nintendo. It's one of those jet fighter games where you move around the screen and shoot up wild getting power ups. The first time I played it on the projector I almost laughed my ass off.
Just after the begining screen, to add effect, they go through a list of checks. Yaknow Like most airplanes do. Engines OK, Shields OK, Weapons OK.
I laughed because the very first check that it says in this game is....IMAGE PROJECTOR....OK!
And since I could read it. I agreed and laughed

ohhh puuullleeeezzeee that burn aint shit. you acted like you made it a major thing. hehehehe. just kidding.

I had a 1989 mitsubishi with a vertical line burn worse than that, and i didnt really care. worked fine for me at the time. Wondering how that line got there? well, oh yea: the vertical circuit was dead. lol.

just be happy the tube is still alive. it could have been worse, you could have fried the whole gun, or killed the filiment, or better yet, be worse than the tube you HAD.

That burn is something youll have to grow used to unless you want to find another CRT, which tells me thats something your probably not going to do anytime soon, finding the CRT you did was actually a rarity in itself.

Speaking of CRTs, i need to find a new red and green for my late model mitsubishi. my green tube is intermittently shorting on the G2 line, and the red is streaking and bleak. (bleedover). both are P16LNM07 tubes. Let me know if you can find these.

Yea the burn just made me mad because the day before it had no burn. I just over reacted.

and Mbates I got this tube by pure luck like you said. Curt just happened to have one and knew what I needed just from a picture of the projector.

A good man to ask is Curt Palm. He'll most likely have your tube as he repairs them and crt projectors and pretty much his life. Just search his name on google

Also there is a forum called AVS. Just search AVS FORUM on google and it'll be the first one. Ask there if Curt can't help you out.
Cheers

Yea ive been there once before, but its been loooonnnggg ago. you might even see my nick there at one point.

Alright I have a technical question of sorts.

The convergence board. (Or raster board as mine says.)
Does it just move the image around?...And is only one signal fed into the rast. board that is split and used for all three CRTs.

I'm trying to troubleshoot why the red is such a different shape than the rest that just cannot be properly aligned.

If the raster board just moves images about the screen and strcehes them, then my problem lies elsewhere.

But if one general signal is fed into this board then the raster board itself is distorting the red.

Just wondering how most projectors would work concerning this.
Thanks
Rudy

Also Mbates14. If you'd like I could tell you the way I did my convergence on the set. Following what I did you should be able to almost get it perfect.
But if you already have your own method that's cool. Just thought I'd ask
Cheers,
Rudy

P.S. I played with convergence for almost a week or more on this set. I have developed a good method.

well the reason your having issues on the red, same problem I have on mine. its jujst the nature of these sets, and they wont get any better than what they are.

Oh ..haha I guess that makes sense to.
I guess the red will never be perfect. Oh well. This was still a very fun project.
And now I have a projector!

Thanks for the helping me out.
Cheers,
Rudy

My projector now sits in my room on a shelf that puts the projector as close to the ceiling as I could get. And convergence is improved greatley when I did this.

But I am posting about something else all together. I wanna build. A mini CRT projector.

http://images.google.ca/imgres?imgurl=http://www.users.qwest.net/~ptaylor/Electronics/TinyCRT3.jpg&imgrefurl=http://www.ccs.neu.edu/home/bchafy/tiny/tinyterminal.html&usg=__lMcIJQPP13UbGuwzpGYIBsZCY-U=&h=960&w=1280&sz=321&hl=en&start=1&um=1&tbnid=JqOXTHCmF6nX4M:&tbnh=113&tbnw=150&prev=/images%3Fq%3Dcrt%2Bveiwfinder%26um%3D1%26hl%3Den%2 6client%3Dfirefox-a%26rls%3Dorg.mozilla:en-US:official%26sa%3DG

You can see in this picture a crt with a screen apparently no bigger than a postage stamp. And it has a rather good resolution.

By using coloured gel or something else. (I havn't put too much thought into this.)
You could get the B&W image to be red or green or blue!(Well all three)

Then it would need some sort of focusing lense. I'm not sure what could be used. But i'm sure on of you will have a good idea of what to use.

Then last but not least. I would need some sort of colour module from another TV. So that each mini crt could get the right intensity for it's given colour. Thus producing a color image!!!

This projector would be so small and so very cool. And I really just wanna know if what I said makes sense? and is it as possible as it seems in my head? I don't plan on running out and buying all this stuff. But if it's possible. I'll start collecting viewfinders.

Please tell me your thoughts
Rudy

P.S. I already know how pointless and dumb this sounds. But I just don't care...it would be cool.

I also have one more question.

There is a noise in my projectors power supply. As I've said before.

The noise is directly related to how much red there is on the screen. No red. Very little noise.

A red screen, and you might think the projector was gonna explode.(not that bad...but...)

Any one ever had a similar problem...?

Thanks
Rudy