GE roundie

[old_coot88]

Does that one use a NE-2 neon bulb in the burst gate area? If so, it can cause color phase/ sync issues even though the bulb appears to be firing normally.

[DaveWM]

Originally Posted by old_coot88

Does that one use a NE-2 neon bulb in the burst gate area? If so, it can cause color phase/ sync issues even though the bulb appears to be firing normally.

Yes it does, it also looks blackened from the inside? Have not tried to observe it in operation. Schematic coming. I will have to see if I have any spare NE-2 laying around. the color demodulation seems to be working ok, it just seems like the tint control does little to shift the tint, does seem to effect the color saturation, not to the extent that the color control does though.

[DavGoodlin]

Originally Posted by old_coot88

Does that one use a NE-2 neon bulb in the burst gate area? If so, it can cause color phase/ sync issues even though the bulb appears to be firing normally.

I read in my book that the NE2-H was a recommended replacement. The grounding of the flyback aux coil (that triggers via this neon) may be faulty. This was an issue in the later rectangular chassis KC-KD-KE as well.

Edit: This book has a good bit of advise about alignment of the color circuit (a quirky GE exclusive). The predecessor chassis CA and those before were RCA design. The tint control is a variable capacitor for example. PM me if you want a copy of the 'CB' chapters.

[DaveWM]

back on it again. Had a weak video out tube, that helped with the brightness.

I was getting all kinds of RF interference, a close exam showed some breaks in the balun mounted on the tuner. got that fixed up then I lost color. I think it was just the color pot grounding on the chassis when it was in the tuner mount on the back of the chassis. Of course I broke the neon bulb while putzing around on the chroma chassis so I went ahead and replaced that. While I had the chassis out I replaced the broken thermistor (it was just being held in place with pressure on the leads) with a CL-90. I also checked the schematic, the hacked in resistor was two 3.3k WW in P where there should have been a 680ohm...oy.... anyway I did not have a 680 on hand so I went with a 830.

there are some .1 brown drops (1kv) in the vert circuit that I will keep an eye on. I did not have any sweep issues but one of them sits right up against the 6EF7 and looks discolored from the heat. I don't like to make too many "fixes" on a working set at one time, so I will try it again and see if the color is working again. If it does I will prob pull the chassis one last time to go ahead and replace those, as well as the .0082 in the feed back and the .001 2kv snubber on the primary of the vert out (its one of those paper in hard ceramic tube shell types).

[tvcollector]

I wish I could see pictures of this set.. It looks to be an interesting set..

[DaveWM]

Originally Posted by DavGoodlin

I read in my book that the NE2-H was a recommended replacement. The grounding of the flyback aux coil (that triggers via this neon) may be faulty. This was an issue in the later rectangular chassis KC-KD-KE as well.

Edit: This book has a good bit of advise about alignment of the color circuit (a quirky GE exclusive). The predecessor chassis CA and those before were RCA design. The tint control is a variable capacitor for example. PM me if you want a copy of the 'CB' chapters.

I have the GE service manual book, is your book the orange one vol one by Robert Goodman?

Some other interesting things about this set. The CB chassis I have is for the round CRT, but the same chassis was used also for the rectangle chassis with a plug in board for the pin cushion (if I am reading it right) My set also sports the later tint control that has a pot with a variactor diode to act as a phase shifting cap instead of the variable cap.

If all goes well I will pull the CRT to remove the lens today or tomorrow, there is only about an eight inch clear spot so it should come of easy.

[dieseljeep]

Originally Posted by DaveWM

I have the GE service manual book, is your book the orange one vol one by Robert Goodman?

Some other interesting things about this set. The CB chassis I have is for the round CRT, but the same chassis was used also for the rectangle chassis with a plug in board for the pin cushion (if I am reading it right) My set also sports the later tint control that has a pot with a variactor diode to act as a phase shifting cap instead of the variable cap.

If all goes well I will pull the CRT to remove the lens today or tomorrow, there is only about an eight inch clear spot so it should come of easy.

Then you people have the nerve to moan about the Motorola 6LE8 circuit.
I had one of those GE's that had a perfect RCA sourced Hi-Lite CRT in it. Needless to say, I scrapped that pig and installed the CRT in a Zenith. It was the last Zenith roundie they made.

[DaveWM]

well the CRT is indeed a RCA Hi lite. At 1st the pic was not that great, but the last time I had it running with color it was looking pretty good that is after I replaced the video out tube. The Cabinet is blonde and in very good shape.

[DavGoodlin]

Originally Posted by DaveWM

I have the GE service manual book, is your book the orange one vol one by Robert Goodman?

Yes, it is.. I learned alot from those TAB books in HS because those 10 year-old sets started showing up on curbs and at VoTech.
My RCA vol 1 book by Carl Babcoke is tattered, bound with tape and smudged with notes, a treasure trove all these years later.

Funny thing is that Robert L Goodman also wrote the Zenith and Philco books the same year. Stan Prentiss wrote the Magnavox book and did a great job.

There are many I don't have in that series, but I just hooked a set of 14 of the books off ebay for $5 each, the original cover price. Hope to "get them for my birthday" next week

[dieseljeep]

I bought a lot of those Tab manuals at the time. A lot of great imformation.
One of the quotes from the GE manual: " Color killer, Who needs it".
If you look at the GE schematics, you'll see a lot of simularity from the 1957 color circuitry design to the later offerings, such as the porta-color and the CB, KC etc. Cheap and nasty.

[DaveWM]

looking good, color is back, decent gray scale. I do have my old friend line pairing rearing its ugly self. My 1st attempt to resolve that was of course adj vert hold, but it jumps in and out of pairing so I will pull the chassis and start with those brown drops in the vert circuit, esp the boost filter cap (.1 1kv) that sits right next to a compactron. while I have it out I will also replace those pesky feed back caps in the vert plate circuit (.0082 is on of them). I will also replace that .001 on the vert primary to ground, just in case some horz is getting in thru the yoke into the vert out trans. I recall having a real tough dog with line pairing that was cured with a new yoke.

the horz prob needs a bit of work as well, its pretty much all the way to one side to lock and will not flop, so I am going to look at the caps/resistors in that circuit as well.

[DaveWM]

argh, pulled the sync sep tube with the set on to replace and see if my line pairing goes away. Well it did as did the video. Being a compacton it is a multifunction tube, I know better to pull tubes with the set on, but I did it anyway and smoked the video driver TRANSISTOR (the only one in the set). Of course there was no actual smoke just a blanked out screen. I had anohter Si NPN handy so popped that back in and all well.

So warning becareful about pulling tubes alway have power off just to be safe.

Will try to see if I can get the CRT out an pop the cat off next.

[Electronic M]

Tip when dealing with multi-section tubes: if you have many spares handy cut off or bend the pins on the section you want to disable and make sure to plug it in the right way...I've done it that way before and it works.

[DaveWM]

popped the cat, did not have to soak as the PVA was soft enough to dig out spaces for the wood wedges (clothespins), about 10 in total. Just have clean it, put it all back together and will call it done. This set has a near mint cabinet, but the CRT red is a bit weak but not bad. After I get it all together I think I will get started on that CTC-5. I put a little restore finish on the 5 and it looks pretty good. Has some nicks and chunks missing down near the legs, but the overall finish is not bad.

[Tony V]

How about some pics