I just purchased a home and the GE 802 was in my basement. Does anyone know what it would cost to restore and the value after completion? Thanks

Eric

Hi folks,
I'm in the middle of a resto of one of these right now and could use some advice. I have recapped the unit, and have good FM operation.
In TV mode I have raster, verticle and horizontal sweep, and good brightness, but no audio or video. I've tested all the 6CA7 tubes in the IF chain, but I can't seem to figure out how to test the 7F8 tube that is the oscillator and converter. I know the oscillator is working as I have FM reception, but maybe the other half of the tube (triode for converter) is bad. The problem is the tube seems to be held in by a screwed in frame of some sort, not just a socket like the other tubes. I can't even seem to see a socket, but I can't believe that wires or components are soldered directly to the tube pins. The set looked to be pretty much untouched when I removed the chassis. This thing is too cool looking to be just used as a radio, especially since in my experience it's tougher to get the sweep circuits right than the video/audio detection and IF.
Any help/hints appreciated.
Thanks,

7F8 is a Locktal Tube. It clicks into place. Give it a good wiggle and tug, and you sgould be able to remove it.

There is a button on the base. Push/tilt the tube toward the button.

Thanks, I'll give it a try, but I certainly don't want to break it. there is a metal band around the base of the tube that is screwed to the chassis, so I can't grab the tube at the bottom.

That might be where they grounded that tube. You might have to remove those screws. Not sure.
Locktal tubes have a metal locking key. That usually is the groundfor the shield. That on most sockets is connected at that point. GE may have chosen to ground it with that bracket.
Also, as stated by Philco, the originator of Locktal tubes.

You gently rock the tube from side to side while pulling up on the tube.

Bill Cahill

removing loctal tubes:


Curt Reed
Post subject: Posted: 06 Jul 2009 16:26
Silent Key

Joined: 31 Dec 1969 20:00
Posts: 34329
Location: Sandpoint, IDAHO 83864
They have a raised dimple on one side of the base. Simply tilt the tuibe towards the dimple and they will pop right out of the socket.
A lot of sets that used loctals will show an arrow on the tube placement chart showing what direction to tip the tube to remove it.
Curt

_________________
Curt, N7AH
(Connoisseur of the cold 807) CW forever!

Loctal sockets can be wrecked by not doing it this way. Curt is correct--even from beyond the grave

Thanks to all. I loosened the screws at the base just enough to get some wiggle room and got the tube out. It tested weak on the oscillator side triode and shorted on the converter side. Once I purchase a new 7F8 I expect to get better results and maybe even a picture! I'm sure I'll find other issues, but need to get this one resolved first and move on from there. I'm sure I'll be back with more questions. Thanks again,
Oh, by the way- I had an idea that maybe someone smarter has already done. On one of my older sets, I was never satisfied with the way the sound was demodulated through the converter and IF stages, so since I was using a VCR/modulator as a programming source, I decided to bring the line out (audio) right to the volume control pot on the TV. I got much better sound that way. Do you think it's also possible to create the proper matching network to bring the video line out from a VCR/DVD/Cable box right to the input of the final video amplifier stage? Think about it- you could just remove the tubes from the RF amp/converter/mixer/IF stages and not worry about all that aligning and whether or not the tuner was dirty, etc. Just have Audio in at the volume control and video in at the video amplifier. The audio works because of the volume control. I don't know if there is a similar need for a pot of some kind or a matching network to properly feed the video out from VCR/DVD to the final video amplifier stage, or do brightness and contrast controls serve that function? Any input appreciated.

Well, I replaced the 7F8 loctal tube that was shorted, and I now have TV sound, but still no video. I have raster and can see a difference when I adjust horiz and vert, but there is no video. All video IF and detector tubes test good. All paper and electrolytic caps replaced.
So close but yet so far away. Any hints appreciated.
Starting to measure all DC voltages tonight, then looking for signals with scope after that.

I posted this in another thread, but thought it wouldn't hurt to put it here, too.
I have an 802 that I'm trying to restore. I have Broadcast, FM, and TV sound working. I have brightness, contrast, and raster, but no video. Changed a shorted 7F8 (converter side), all IF tubes and detector tube test good.
For some reason contrast control also has an effect on volume level. Can't figure that one out, but maybe it's a clue for someone as to what might be wrong.
I'm feeling really close on this one, but something is still amiss. All paper caps replaced along with Electrolytics.
If I could just get the video going I'd be all set and could put it back together and start on the next killer project- a Magnificent Magnavox Imperial Hutch w/ AM/SW receiver, FM Tuner, Huge AMP with 4 6L6's, monster woofer and 3 tweeter array. But I must finish this project before I get to move on to the next.
Any hints appreciated.

Try bypassing the IF section and injecting a video signal into the video amp.
You also mentioned measuring voltages a few posts up. Did you find anything amiss?
Have you checked the pots--especially the contrast as you had mentioned a problem there.
I always recheck wiring against the schematic as well if I've unsoldered anything.

The contrast control on this set varies the dc bias going to grid 1 of the 1st and 2nd video IF tubes. The sound gets picked off after the first video IF, so I think a slight volume change with contrast setting is normal on this one.

For bypassing IF and going right into Video Amplifier V14 6AC7, I assume you would suggest pin 4, as this would be fed from pin 5 of video detector V15 via choke L10, right? If that works, I'd like to just have a video line in and audio line in on the volume control since most progam material nowadays is in the form of direct audio and video and not modulated RF. Think of the savings in time and tubes! (I guess we still need sync for the sweep circuits though)

I don't have the schematic but yes, the grid which on that tube is pin 4. A composite video signal with ground to chassis. Some of the guys here run their sets like this with the sound to the volume control.
My disclaimer: I am not a pro--I have only restored one set

[EDIT]
Just realized this was your thread Bob--sorry I drove it OT a little

I just grabbed the schematic from earlytelevision.org. This is a strange set. To have sound, the tuner and the first video IF stage have to be working. That leaves the second and third IF stages, the detector & the video amp as a source of problems. Injecting video into the video amp would be a good troubleshooting technique. But note that the contrast control on this set varies the gain of the IF strip, not the video amp (on most newer sets, the contrast control varies the gain of the video amp). That means that if you inject video into the video amp, you will have no control of the contrast. This also explains why varying the contrast affects the sound.

Perhaps a new thread should be created for this set.

Ok, I've figured out a few more things with this set. Unfortunately, others have been in here before me. Voltages were somewhat lower than expected in IF chain of tubes, and I found out that there is some mis-wiring that has taken place, but I need a little extra help in putting humpty dumpty back together again.
Someone had connected the 33K resistor in the horizontal section that should be in series with the blue wire from the transformer to pin 8 of V21 Horiz Output tube 6BG6 to ground. it should not be connected there. the other end of the 8200 ohm resistor that is connected properly to pin 8 has a red(orange?) wire connected to it instead of a blue wire, and pin 1 (not used) has the .001uF cap to ground. My guess is the 33K resistor was/should have been connected to this unused pin along with the .001 cap, and then the correct blue wire from the transformer gets connected to the other side of the resistor. Now I have to determine where the red(orange?) wire was supposed to go.
If I could get a picture of the bottom of the chassis from someone who has one it would be most helpful.
Thanks,

Do you still have this set? I need a picture of the bottom of the chassis where the horizontal tubes V21 and V22 are to put things back together properly after some hack repairs were done in the past. I can't see what I need from the pictures you originally posted.
Hope you still have the set.
Thanks,

Do these help?

Awesome, thanks. Almost there, but not quite. Can you show me a shot of the 8200 ohm resistor that comes off of pin 8 of V22 (6BG6) and what is connected to the other end? I'm trying to figure out what and where L2 and the 33K resistor are connected, and where the 'blue' and 'orange' wires from transformer T25 are connected. I don't seem to have an L2 on the chassis anywhere I can see, and the 33K resistor is not in series with the cap of the high voltage tube as shown on the schematic, but instead is under the chassiss down near the two 330 ohm resistors and the 8200 ohm resistor. On my set that 33K resistor is made up of two resistors in parallel. I'm mostly confused by all the things that seem to be connected to pin 1 on the V22 (which is an unused pin that they just used to tie a bunch of stuff to.
Any help appreciated.
Thanks,