General Electric AC-Chassis - Videokarma.org TV - Video

zenith2134 · #1 08-28-2008, 10:12 PM

Hello. I was given a 17" GE remote set with the AC chassis recently. It plays quite well, with a very bright and vivid picture, just that its so, so sensitive to mains-fluctuations. For example, if I were to switch on my celing fan or air conditoner, the pic would momentarily squeeze inwards and then bloom considerably. I would just swap out the filter caps ordinarily, but I wanted to pick your brains and find out if there was somewhere in particular I should start with first. Pressed for time lately.

Anyways, the set was built in Portsmouth, VA in April of 1982. I'm kind of surprised at the quality picture this GE puts out. In the past, I've noticed GE sets were typically sort of washed-out or hazy. Maybe I've just been accustomed to sets which needed some kind of repairs. But this TV is quite the champion. Plus its got IR remote, which makes it easier to use with my digital boxes.

radiotvnut · #2 08-29-2008, 12:11 AM

First, I'd check the B+ to make sure it's running within spec. Then, I'd look into the voltage regulator circuit for trouble. You might want to change the electrolytic caps in the power supply. I've seen these chassis in the 10" "portacolor III's"; but, I've never had to do any in depth troubleshooting on one. I did have one of those 17AC chassis sets with a mechanical tuner and mine had a very bright, sharp picture (unlike most GE's).

You may not be able to completely eliminate the problem; but, I think the problem can be minimized.

zenith2134 · #3 08-29-2008, 12:28 AM

Thanks for the quick tips! Yeah, I don't know what they did here but this set has a smokin' picture. The tube code is 188-23, classic GE.

Tomorrow I'll get a chance to dismantle the set and check this out. I'm probably going to start by doing a 'shotgun' replacement of the lytics in the power supply.

radiotvnut · #4 08-29-2008, 01:11 AM

Isn't that a large neck inline tube that uses the convergence coil assembly with two knobs on top of the assembly?

While you're in there, look for any bad soldering. GE was famous for that at one time.

I believe the AC chassis was the last true GE chassis to be used in a 10", 13", or 17" set. Somewhere around '83 or '84, GE started outsourcing the chassis from Matsushita and, later, GoldStar. Those Matsushita flybacks are always bad in those GE branded sets.

If you ever find a PC (19" and 25") chassis GE from around '86 or '87, you might want to grab it. I'm pretty sure the PC was the LAST true GE chassis before GE sold out it's consumer electronics line.

zenith2134 · #5 08-29-2008, 09:48 AM

That's the one...it has the knobs on top of the tube for convergence.

Its definitely a GE chassis.

zenith2134 · #6 08-30-2008, 06:30 PM

I took radiotvnuts advice and resoldered a whole bunch of module-plugin-connectors. It actually helped a little bit. As it stands, i haven't replaced any parts yet. Thats next.

rcaman · #7 08-30-2008, 10:05 PM

consumer reports gave those sets high marks as for as picture quality ranking above the rest of the manufactures. i worked on a ton of those and they had a hell of a pictue on them. they will lose the flyback over time replaced a ton of them part ep77x? it seemed the harder you run one of those the longer the crt lasted. it is a keeper. steve

zenith2134 · #8 08-30-2008, 10:30 PM

Really? I wonder how driving it hard would make it last longer? Sort of reminds me of the instant-on TVs. IIRC, alot of members here felt that they lasted if instant-on was maintained, but die off once they are unplugged.

Guess that the cathodes need a strong input to keep working in this tube.

One thing is for sure, and i don't know how to explain it: For a 17" set, the whine of the horizontal oscillator circuitry is exceptionally loud. I can hear the high pitched whine of this set outside in my yard. Even my 35" Trinitron (1999 model) doesn't sound as loud. Not that its a big deal, just interesting to note.

This TV has a copy of the tuner block diagram and schematics for the entire chassis in a folded-up little manual which is kept in the back cover of the set and is only accessible from the inside.

The manual's instructions for setting greyscale are a bit whacky..... I'm accustomed to just using a dark scene to set background levels and then snow to set the drive levels.

On this set, it instructs the serviceman to short two posts on the video output board and set only two of the three background levels. Meanwhile, its got adjustments for all three.

I re-set the convergence before. The knobs on the crt neck (which radiotvnut pointed out) are very helpful in getting it right. There are clearly marked knobs for vertical and horizontal convergence for each color. As given, the set looked OK but I purposely threw off all the converging knobs so that I was forced to get it 100% correct. It looks even nicer now.

Thanks for the tips so far, and by all means keep em coming!

zenith2134 · #9 08-30-2008, 10:36 PM

Was watching an 80s marathon. Heres some pics.

radiotvnut · #10 08-30-2008, 11:29 PM

I seem to remember GE having a problem with squealing flybacks even in the old tube type chassis. I guess they still had the same flyback squealing problem by the early '80's. Of course, your set was not made too many years after GE discontinued tube-chassis sets. Some say that GE made the 10" tube portacolor as late as 1980. At any rate, I think GE was one of the last US manufacturers to build a tube chassis TV.

You're lucky that the service manual was still in the back. Those are almost always missing, especially if the set has been to a repair shop.

zenith2134 · #11 08-30-2008, 11:37 PM

I wouldn't be surprised if GE put the same flybacks in the AA-chassis sets and tube sets. Also, I recall GE made a lot of stuff for other companies, like arcade monitor chassis and stuff like that. Once saw an 80s GE chassis in an Invaders game from that time. What happened was I went into an old tv repair shop asking if they had equipment or old parts for sale, and saw the machine since they were working on it. The guy told me that GE made a ton of parts and even whole chassis for arcade games back then. They were (are) HUGE, in every field it seems.

About the service manual... I don't think this sets been in a repair shop, but I can't be sure. For one, I usually see one of about five stickers that the repair shops around here leave on the back of sets, and this has none.

Its funny how the little manual has a warning about the shop returning the literature back to the customer, and like you say, they rarely did.

radiotvnut · #12 08-31-2008, 01:04 AM

I know GE made some TV's for Western Auto (Truetone) and JC Penny. You can look at the sets and they scream GE. They just have a different name plastered on them. I'm sure they are harder to find than the actual GE branded sets.

I was just thinking about the AA/AB/AC chassis line and how they were used in 10", 13", and 17" sets. I've had examples of all three. For some reason, the 17" version produced a far superior picture to the smaller screen versions. Really, the picture on the 10" version looked almost like a tube portacolor.

bgadow · #13 08-31-2008, 11:18 PM

I think the trouble with the 10" version is it has the same phosphor 'dot' size as the bigger screens, so it is really course on such a small screen. They are some tough sets. GE, of course, was (is) all about value-how cheap can we make this widget and still have it work okay? It took them awhile to make a really good color tv that way. I grew up around lots of GE sets and the flyback whine was really common (I never paid it any mind, just figuring that all sets must do it, until I started dragging home other makes) and the voltage flucuation issue sounds kinda familiar, too.

I have an elderly neighbor with a 19" GE from the 80s-push button tuning, remote I think. That set is in a back room and probably hasn't been on in years. Though I don't have the room, I should make an attempt at saving it, before it gets tossed.

zenith2134 · #14 08-31-2008, 11:52 PM

Yep, i'd save that set Brian. I feel like these will be rare one day. The 80s sets aren't a big appeal to most any collector, yet they are great sets. They usually just get dismissed as 'old' and are thrown out.

From what i've read, the General built em cheap yet they last forever. Good philosophy when you think about it.

I have a '66 portacolor with the 11sp22 crt which looks darn awful. Colors are vibrant and nice, but man those phosphors are terribly coarse! Again, it works and its color, but the resolution is real bad! And the chassis tubes look to be all original, 40-plus years later!

radiotvnut · #15 09-01-2008, 12:19 AM

Yes, '80's sets are generally overlooked now; but, wait another 10 years. Look at sets from the '50's through the '70's. Ten years ago, most collectors wouldn't give them a second look. Now, look what's happening with sets of that vintage.

I need to get busy and try to locate one of those tube portacolor's. Back in the '90's, they were real common finds. I don't think I've had one since about '97. The one that I'm really kicking my butt over was the November, '76 model that I sold for probably $15-$20 working. Back in the '90's, TV's were just something for me to fix and sell to fund my antique radio habit. I really didn't have an interest in collecting them nor did I see the future collector interest in them. Now that I'm older and have developed an interest in TV collecting, those once common sets are not as common anymore.