Quote:
Originally Posted by Palinurus
Thanks, Zeno. I see a 9-89-R for sale for $20, but it doesn't appear to have the IC that mine does. I'm hesitant to order it. Is the IC the black card-like piece attached to the module? The 9-89-R doesn't appear to have one. My IC is numbered "Zenith 105-110" with another number E-181-7833. It's also referred to as "IC 1201 THICK FILM" in the diagram pasted inside the TV.
|
No, the 89 module is the kine driver. If that's bad, you'll have bad grey scale.
EDIT: I see where Zeno advised soldering the thick film ICs on the 88 and 89 for general maintenance, not to fix the no color condition. Good idea. Use enough heat and I'd add some flux to it. The solder on those gets crusty and doesn't like to reflow easily.
As Zeno said, it's the 86 board right above it.
There are two ICs on that board, but most problems are either bad connections on the ICs, bad connections between the module and the chassis connectors, or adjustment. Every once in a while we'd see a bad IC.
If you have an early module, the ICs are not mounted in a socket, they're mounted in individual pins. Remove the ICs, clean the pins with fine sandpaper or pen eraser (the leads are probably black with oxide), clean with alcohol, and put the chips back. If the color comes back, I'd remove the socket pins and solder the chips directly to the board. You can always buy standard 16 pin sockets and replace those crappy pin sockets. Zenith eventually soldered down the ICs in later versions and in rebuilds.
There are 4 adjustments on the 86 module, one of them is color killer. See if you can find a SAMs - I don't remember the adjustments any more..
There is also burst kill switch on the module used to set the 3.58 osc that gets dirty. Clean that as well.
I believe there might also be one or two electrolytics on those boards. At this age, they're likely to be iffy.
EDIT #2: I seem to recall there were several suffix versions of that board (maybe 6 or more), but they all subbed into two classes. I don't remember the numbers but they look very similar but won't interchange. If you do put the wrong one in, no harm will be caused.
John