Someone brought by a '99 27" Zenith with a bonded yoke Thomson CRT that they wanted fixed. They said it had audio; but, no picture. Upon testing, it indeed had no picture except for the OSD and menu. Upon further examination, I turned up the master G2 control and got a washed out B&W picture. Going into the menu and running the picture and color controls up and down did nothing whatsoever.

In the past, I seem to remember replacing a few jungle IC's in late '90's Zeniths for similar problems. I think I remember one where the color was wide open and another one that had no horizontal drive coming out of the IC.

This set uses a Toshiba TA1268N 56-pin jungle IC and I happened to have one on a junk board. After the IC was replaced, the set worked normally. The set still had a repair tag from '09 taped to the back and it was obvious that this same IC had been replaced at one time.

I seem to remember the technician at the local Zenith dealer telling me that this jungle IC was a high failure part. I wonder if they failed due to an internal defect or if they were sensitive to lightning/power surges.

Here's a video I made of the set:
http://www.youtube.com/watch?v=qtwKQ2aTJiM&lc=GLWDMgm7yDQ1Z5segcFRlj0zgQY71uEQR0s012gYR4Y

So weird, I've never seen the jungle IC's ever fail. I thought they are actually quite robust. Is this only to Zenith, or did other manufacturers have issues too?

Set looks good!
I replaced the Jungle IC in one of those ultra cheap 5" Chinese Jellybean B&W sets once, it had raster but no video, the chip was getting hot so I guessed it was the problem and it turned out it was.

Perhaps heat is what causes the failures; perhaps installing a heat sink on the IC would be a good idea?

Yes we did put quite a few jungles in the late Zeniths.
Maybe its static, if so could try a tape on shield to
ground like Toshiba did, but whats the point now??
Never saw anything from Zenith about it, but then
again GS had all but gutted them by then.........

73 Zeno:smoke:

So weird, I've never seen the jungle IC's ever fail. I thought they are actually quite robust. Is this only to Zenith, or did other manufacturers have issues too?
A good lightning strike almost guarantied killing one.
Also there was the Toshiba TA8680. Went in Toshibas, Sharp,
Gold Star & others. Changed tons of them under warranty
for buzz in audio or AFT problems. New ones were updated
& ran fine. So they can go bad, not common or rare.........

73 Zeno:smoke:

I once replaced the jungle chip in a 32" Sony Trinitron from 1997.
Pain in the ass to replace but keeps your soldering skills sharp!

I wonder if it's the jungle ID that's broken in my Dads bedroom TV, a 32" KLH. One of the S-Video inputs, on the OSD, it flickers between "S-Video" and "Video 2", which if no S-Video is plugged in, it becomes composite AV 2 input. But even with S-Video plugged in, the TV flickers the text like it doesn't know, and there's a lot of distortion in the luminance on that input, but ONLY when chroma is present. It's very weird, and annoying.. Luckily the TV has another S-Video input that works fine.

Oh, the TV has an odd 240p mode, in which case it it just merely combines the even and odd fields into one field like 240p, but no actual deinterlacing is performed. It's really weird the TV has that.

they did fail a lot in those zeniths. i hope the only reason you are replacing it is because of the thompson crt which will be good. i have a few of the jungle chips im sure. steve

Had it had a real Zenith CRT in it, I wouldn't have bothered. It's now fixed and the owner is happy.