Hello Guys,

Great forum here! I just picked up this old Motorola Quasar model # WU821FS

The audio comes through great, but the picture is nothing but snow, and occationally a black bar on the bottom warbles it's way through with a thin green line above.

I'm really a novice with old tv's(this is my first purchase, got it cheap). I'm wondering if you all could get some sort of feel of what the issue might be by taking a look at the pic w/ the set turned on.

Thanks to Dave at JustRadios, I was directed to a schematic over at Sam's. I'll be getting one of these for any future servicing needs.

It appears that the last time this television was serviced was 1982 w/ a 2 year picture tube warranty. I am the 3rd owner, but the 2nd owner received it after moving into the house (1st owner left it there), and had it stored away from the get go.

Thanks for any help!

I would say bad capacitors in the vertical section...check vert. output tube too if it is the tube type. make sure you follow all safety precautions on dealing with high voltage in TV's if you go in to working on it, as it can be very dangerous.

Hey Chad,

Thanks for the quick response.

This solution would be for both the lack of any reception AND the black bar issue, right?

On the back, everything pops off nicely w/ the little tabs, but the left side does not because it looks like the rear control panel has been tacked in, thus I cannot remove the back board.

I've attached a few more pics of the rear of the unit. As you can see from the rear control panel, it seems to be tacked shut.

Also, I'm curious to know what the cutout w/ the metal piece is on the lower left area?

Thanks

That is the lock for the drawer...this is a Works in a drawer set and you release that latch to slide the drawer out to the front. Most of the circuitry is in the drawer.

I'm trying to figure out how to release this latch? Any tips?

It seems like you have to push down or pinch in the two sides of a bar going across the latch. I hurt my hand on it the last time I did it so I would recommend putting on gloves while pressing the latch release.

Look for the FA board. If not mistaken, this has the 6CW5 vertical output tube on it, and the horizontal oscillator tube. 6CW5's can cause lots of issues.

I have not seen one of these sets in at least 20 years. :)

If not mistaken, you need to remove that 1/4" hex screw near the power connector before you pull the drawer out the front of the set. I can see it in your pics.

Isnt there supposed to be some kind of jumper on the 75 ohm input in order to use the 300 ohm input on these? This might be the cause of the reception problem. Has the uhf been tried yet? Most of the tv's that i have had that produced snow functioned properly once proper signal was applied unless tuner was extremely dirty.
-Tony

I have it on UHF at the moment, and it only picks up audio from some strange 3ABN (3 Angels Broadcasting) channel that kind of freaked me out in a Poltergeist sort of way...hah.

Alright, I hooked it up to a cable box via the 300ohm VHF set screws, and attached some pics showing the result.

Here (http://www.soulajar.com/inmotion.MPG) 's a 3MB video clip of the television in action w/ the cable hooked up...

I figure this might be easier to diagnose than by mere still imagery.

I haven't seen your video because all I have is dial-up. But if the line crawls it is could be a capacitor in the vertical section. In particular, look at the cathode circuits in both the vert output and oscillator.

If there is no crawl but just bad height and linearity it could be a bad tube or off value resistor in the vertical circuit.

Also, pay attention to any other clues such as a slow crawl that warps the picture which would then indicate bad power supply filtering.

I used to have almost this exact set. I can't remember for sure, but arent the height and vertical linearity controls on the end of the vertical board? Don't you have to open the drawer to adjust them? Maybe this will clean up with just adjustments.

AFAIK all Motorola Quasars came with a schematic and service information. It's probably taped inside the cabinet.

John

Hmm this might save me $20 on buying the schematic booklet.

So in order to pull the drawer out, I need to remove the hex screw? Is it the metal one on the paper panel, or the plastic one?

I believe you need to remove the metal screw right below the antenna terminals.

I got the screw out, and voila! Here's some pics w/ the drawer out.

Now I still need to figureout how to get those tacks out so I can remove the entire back panel.

I haven't seen your video because all I have is dial-up. But if the line crawls it is could be a capacitor in the vertical section. In particular, look at the cathode circuits in both the vert output and oscillator.

If there is no crawl but just bad height and linearity it could be a bad tube or off value resistor in the vertical circuit.

Also, pay attention to any other clues such as a slow crawl that warps the picture which would then indicate bad power supply filtering.

I have archaic webtv dial up and can't believe I was able to download the video images. Good diagnostic tool. This set looks very fixable. It can't be stressed enough...High Voltage is DANGEROUS!

-Steve D.

Most definately I understand the precautions. I would never work on this myself, as I don't have enough experience working with such high voltages. My guitar tech, Chris Siegmund, builds tube guitar amplifiers and would be my first candidate to work on these. I thought it'd be wise to get a general concensus from a group that are familiar with this avenue before taking it over to him. You guys have been great!

If you do need to service the vertical section, it is located inside the drawer on one of the circut boards. It is the one on the bottom, with the two tubes in it. The small orange plastic cylinders on the board are electrolytic capacitors, and if the vertical problem can't be cured by fiddling with the controls, these are probably what has gone bad. They are very ease to replace, as the small board can be removed from the drawer, by very carefully pushing from behind it (if you can get to it from behind, be careful, as those long silver cans on the other side can store high voltage even after the set is off and unplugged), you should start to feel it pop out. This is another cause of problems on these sets, as the pins on the boards (called modules) might not make good connection to the rest of the set, and can cause problems, though they are usually more major than this, such as no vertical deflection at all (only a thin horizontal line in the center of the screen), or no color.

I still need to figureout how to get those tacks out so I can remove the entire back panel.
Tacks? I don't know what you mean. There is probably another screw or two in the back, but it's mostly held on with metal clips. You just squeeze them and they pop through the rectangular holes.

John

There are tacks holding the plastic panel to the back piece...so I thought these were the reason why the back panel wouldnt come off, but sure enough it was the same hex screw I took out to bring the drawer out.

Find the 6CW5 tube. It's a tall 9-pin. That is the board with the vertical circuits on it. Chances are good that the big caps in the power supply have issues, too.

Is the horizontal and damper tube installed on a small separate chassis? Dont mess with these tubes, as it looks like you have good width on the images you provided.

I see a few trim pots that adjust vertical characteristics...Is it possible that I would just need to adjust some of these to fix some of the issues? Or is a cap and/or tube replacement definate?

iirc thats the ja board.
replace all the orange ero electrolytics
they are much more likely to be the problem than the 6cw5.
that set is a easy fix.


Look for the FA board. If not mistaken, this has the 6CW5 vertical output tube on it, and the horizontal oscillator tube. 6CW5's can cause lots of issues.

I have not seen one of these sets in at least 20 years. :)

If not mistaken, you need to remove that 1/4" hex screw near the power connector before you pull the drawer out the front of the set. I can see it in your pics.

Adjustments are just to compensate for small changes in picture size due to tube aging...this case looks more severe and I agree that the problem here is likely bad caps.

K, so I located these caps...They are the radial electrolytic type, correct?

There were 2 on the same board as the tubes, and one more on a board above...

2 on the tube board read:

8/50 A36 20
50/50 A29 20

The one on the board above read:

40/50 E2 A 30

I'm assume the 50 is voltage? Is the prefix uF? If so, I'm familiar with 10uF and 47uF but have never seen 8 or 50, or 40 for that matter...

Thanks

iirc thats the ja board.
replace all the orange ero electrolytics
they are much more likely to be the problem than the 6cw5.
that set is a easy fix.

Thanks, You're right. Recalling things can be fun, especially when you haven't look at a Quasar TV in about 15 years. :scratch2:

There's a simplified schematic on top of the drawer that signifies each section (this being the FA section). It doesn't say much about each part (other than tube names, and adjustment areas)....more of a map than a true schematic.

Although, by looking at this I noticed that the 3rd cap in question is not a part of the FA section that we are dealing with.

I've attached 2 pics of the 2 caps, labelled accordingly.

Yes, those are the two caps that are probably giving you trouble, the 50uF cap can be replaced with a 47uF, as they are almost the same, the industry switched over to the slightly different values for a reason that has slipped my mind. You should also be able to replace the 8uF with a 10. If you replace these two little caps, you should have a nice fully working set on your hands. :D

I headed down to Radioshack and they had some radial electrolytic caps for 47uF and 10uF, but both were at 35v rather than 50v...Would these suffice, or should I stick with the 50v?

P.S. If anyone can get the Sams document for this (#1159-2) that would be wonderful. This way I can be sure that I need a 47uF not a 4.7uF, etc.

Thanks a million

You need to go with the 50's.

Just placed a $.15 order with Futurlec...with the $3 shipping of course ;) Looks like it'll take a week or two to get here, so until then (unless I find some at my guitar tech's house Friday) I'll admire it's looks with the power off.

I also have a Works in your drawers (works in what drawer) that had roughly the same vertical issue. Turned out to be low B+ supply voltage thanks to the multi section cap in the voltage doubler.
As a Motorola radio tech for 20+ years I can tell you that Motorola was very good at making "oddball" rating parts for good reasons. Your 50uf cap is one example along with other even number/odd value parts as we used to call them. Motorola wanted to keep the radio service within its own service depots and the wierd value parts was a way to keep you coming back. You will be happy to know that the pins and sockets used on the boards are still available for Motorola as they were used in the Micor unified base stations and micor mobile radios, these are a real troublespot for both the television sets and radios that used them.
Last to look for is to make sure that the regulated low B+ I believe is known as the 20 volt supply is right at 20 volts, anything above or below has caused me much grief with my STS-934 chassis including loss of color lock and vertical stability issues.

Is it MONDAY yet? Gotta get back to my bench!
Tech-109