1960s vintage 9" GE B & W Portable TV has no Picture

[Captainclock]

Originally Posted by Gregb

Just use those little yellow axial lead caps and bend the one lead over so it goes down into the hole in the board. Worked fine for me! I did also find a few resistors that were way out of tolerance so check them as well. This is all really easy to do with the CRT removed.
I am just in the process of putting my Hotpoint back together and will have a picture or two tomorrow, it works really good.

Gregb

OK Sweet, I'm looking forward to seeing what yours looks like so I know what to expect out of mine when I get mine finished.

and I kind of guessed that's the kind of capacitors I would of have to use but I wasn't sure, which is why I asked.

My car is going to need a $500 shock and strut repair so I'm going to have to save up for that by mowing my parents lawn sometimes during the summer.

So anyways Hopefully I can still get some of my spending money from my mom that I can use to get the capacitors I need for this TV to get it up and running again. Because the guy at my church who gave it to me would like to know when I get it going because I guess it was the TV his parents used when he was growing up and he would love to see a picture or a video of it running again.

[Captainclock]

Well I finally was able to order some capacitors for this TV but now I just need to know which capacitors I should replace first considering the issues I was having (vertical issues), especially since I don't have the service manual for this TV it would be nice to know which capacitors in this tv are involved in the vertical circuitry, so I can replace those first since that's what's having the most issues right now.

Also I took a look at the tube in this set and noticed that it doesn't have a HV Anode anywhere on the picture tube, just wires coming off of the little assembly on the neck and that's it, I also took a look at the tube and found a manufacture date code, the code was 6024 (which if I'm reading it right would be the 24th week of 1960) but then I saw a tag on the top of the tube that said Rev. 4-63, so the tube in this set is definitely not original but it is a GE Tube though so it might of been a replacement done under warranty.

Thanks for your help.

Levi

[Electronic M]

Look at the tubes with vert. labeled next to them in the set's tube chart and the vertical output transformer.....All caps connected even through resistors should be changed. There will be a lytic connected to the cathode of the vert output (most likely the problem) and one filtering the B+ connection of the output transformer, change them.

In a monochrome TV you need to know the generic block diagram of circuits that applies to any monochrome TV....Most apparent problems are easily correlated to their given 1-3 (most can be tracked to only 1) circuits, then it becomes a matter of replacing parts in that circuit. You should know this, and not need us to tell you, if you plan to service TVs.

[Eric H]

The HV goes into the base of that tube. The pin is off by itself if I recall right.

[Captainclock]

Originally Posted by Eric H

The HV goes into the base of that tube. The pin is off by itself if I recall right.

What I mean is that this picture tube doesn't have the 2nd anode suction cup thingy that most CRT TVs have is what I mean.

Anyways This TV has a 4 MFD 50 Volt Electrolytic Capacitor in the circuit and I was wondering if a 6.8 MFD 50 Volt electrolytic capacitor would be a good replacement for that capacitor, I'm curious because I don't have any 4.7 MFD 50 Volt Electrolytics in my capacitor stash and the only 4.7 MFD 50 Volt Electrolytic capacitor that Radio Shack has is an axial leaded one which I wouldn't think that using an axial leaded Electrolytic capacitor with one side exposed would be very safe without having some sort of shrink wraping over it so that it doesn't arc against something else in the TV.

[Eric H]

Originally Posted by Captainclock

What I mean is that this picture tube doesn't have the 2nd anode suction cup thingy that most CRT TVs have is what I mean.

I realize that, I was just pointing out it doesn't have one on the side of the tube because they ran the High Voltage through a pin on the base of the tube instead.

The 6.8Mf cap is probably close enough, it's more than 50% over but depending on what it's for it probably wont matter much.

[Captainclock]

Originally Posted by Eric H

I realize that, I was just pointing out it doesn't have one on the side of the tube because they ran the High Voltage through a pin on the base of the tube instead.

The 6.8Mf cap is probably close enough, it's more than 50% over but depending on what it's for it probably wont matter much.

That's why it would be nice to have a service manual for this TV, but I don't want to pay $20 for a Sam's Photofact for this thing because that's kind of rediculous to pay that much for a simple 4 sheet document that's over 50 years old and that's probably a very poor scan at that.

Also you never answered my previously asked question concerning where to start first when recapping this TV because I just ordered the caps for this TV but I would like to know where to start in the chain of things (which caps are for the vertical out stage where I'm having the main problems right now) and where are the HV/Horizontal out stage caps at?

Also the really weird valued .0039 MFD 400 Volt capacitor I had ordered a .0047 MFD capacitor to replace it, is that ok? I'm just wondering because there were no other values that came close to that funky valued cap at AES except the .0047 MFD.

[Eric H]

If you know the number you can get a Sams from John Kendall for $9.00 http://vintage-electronics.com/
If you don't know the number he can look it up by model number.
eBay is another place to get one for cheap.

As Electronic_M explained above you could find out which tube is the vertical output from the tube chart and start there, one of the Electrolytics is probably also part of the vertical circuit so that would be a good one to start with.
The set is so simple it can be completely recapped in an hour or two anyhow.

The .0039 is probably close enough, depending on what it does, if it's part of an oscillator circuit (Vert or Horiz) it might throw it far enough off frequency that it can't be brought back in sync with the adjustments given, you won't know until you try.

[Captainclock]

Originally Posted by Eric H

If you know the number you can get a Sams from John Kendall for $9.00 http://vintage-electronics.com/
If you don't know the number he can look it up by model number.
eBay is another place to get one for cheap.

As Electronic_M explained above you could find out which tube is the vertical output from the tube chart and start there, one of the Electrolytics is probably also part of the vertical circuit so that would be a good one to start with.
The set is so simple it can be completely recapped in an hour or two anyhow.

The .0039 is probably close enough, depending on what it does, if it's part of an oscillator circuit (Vert or Horiz) it might throw it far enough off frequency that it can't be brought back in sync with the adjustments given, you won't know until you try.

The original Capacitor was the .0039 MFD and the one I had ordered to replace it was the .0047 MFD all the new capacitors i ordered were 630 volts so hopefully that should be ok. anyways I was actually thinking of trying to find a free download of the service manual, because I really don't have a whole lot of money to throw around at ordering stuff like service manuals and what not as my only source of income currently is Disability checks from Social Security because of my Autism and I'm currently unemployed and have been trying to find a decent paying job for almost a year now without any luck, and the money that I get from disability is handled by my mother, so the only spending money I get is $30 every two weeks and I can't just randomly blow that $30 all at once on just buying parts and service manuals for my repair projects because my mom would be upset at me if I did that.

[Eric H]

I probably have the Sams for it somewhere around here, If I can find it I'll scan it for you, I can send a copy to the ETF too so it'll be available in the future.

[Eric H]

Here's a link to the Schematic, Right click and "Save As"

http://vintagetvsets.com/schem/359-7%209T001.pdf

[Captainclock]

Originally Posted by Eric H

Here's a link to the Schematic, Right click and "Save As"

http://vintagetvsets.com/schem/359-7%209T001.pdf

Thanks very much for the copy of the sams, I have now figured out that the reason why I'm having issues with the bottom of the picture being folded over on itself and not have very good vertical linearity is because possibly the 10C8 Vertical Output tube might be either very weak or bad, there are two 10C8 tubes in this TV the other one of which goes to the Audio Amp stage, which works fine so I might try substituting the Audio Amp stage tube for the vertical output tube and see if that makes a difference with the vertical linearity in the picture if it does then I know that the 10C8 tube is what's causing my problems and not necessarily capacitors (although I'll probably replace the capacitors anyways since I got them just to be on the safe side).

EDIT: Iwas able to swap the Audio Output tube and the Vertical output tubes which are both 10C8 tubes and I was able to almost fill the entire screen except for the very top of the screen and that was with the height and vertical linearity controls jacked up about 3/4 of the way up.
So it seems that now I know that the TV's issue is a combination of a weak 10C8 tube and some bad capacitors in the vertical section. Which like I said I had already ordered some new capacitors for the TV and should be getting them by Thursday.

[Captainclock]

Ok So I got my capacitors today and I just finished replacing the old capacitors and I went to test the TV out and for some reason the TV is giving me a very poor picture that's nothing but a small line in the middle of the screen that rotates in a circle (kind of like an analog tape counter except a little faster) and the screen goes completely dark at either end of the brightness and contrast controls but is visible in the middle of the controls, I also have to mention that a couple of traces lifted when I removed the old capacitors (the traces that the capacitors soldered into lifted but didn't break). I have a photo of what the TV is currently doing, that I've posted below.

[Electronic M]

Looks like your B+ is low. Focus on the PS lytics.

[Captainclock]

Originally Posted by Electronic M

Looks like your B+ is low. Focus on the PS lytics.

Ok but why would of the power supply caps suddenly gone out when they were working fine for the most part before I recapped the TV? Because before the TV was competely filled except the bottom part which was folded up on itself but now its not even completely filled and the image on the screen rolls around like a can on the ground or like a cement mixer truck, and the brightness and contrast controls are being screwy.