[radiotvnut]

I've ran into a lot of 9-160 TV's and 9-181 TV's that would have failures of multiple modules at the same time and it's highly possible to damage a new module because of a defect on one of the remaining modules. This was especially true on the 9-181/9-186 style chassis. I remember one 9-181/186 chassis that caused me to lose some hair. The set acted like it was trying to start; but, all it would do is make a roaring noise from the speaker and all power supply voltages were low. This set used a standard power/volume knob with an electronic tuner. When I unplugged the power cable going to the tuner, the rest of the chassis came to life full blast. The problem was a dead shorted electrolytic capacitor inside the tuner. I don't remember the value; but, I think it was something close to 1000uf, 25V.

One thing I forgot to mention was that the 9-160 sets were known for bad solder connections all over the sweep module. These connections usually cause intermittent power up, a set that would shut down and make a roaring sound, and a set that would blow horizontal output transistors.

I remember one 9-160 set that was given to me that had a shorted HOT and blown fuse. I resoldered any suspect connections and replaced the HOT and fuse, only to have the set make a roaring sound. I don't remember what all I replaced next; but, I seem to remember one of the horizontal driver transistors, a diode, and an 8-pin IC in the power supply being bad. After that, I turned it on and the flyback violently arced. I've seen those 9-160 flyback transformers go up many times and they will get your attention. Zenith wouldn't sell just the flyback; instead, you had to buy the whole board. I ended up taking a flyback off another board and the set worked and I feel like it was the arcing flyback that took out the other parts that I had to change. I don't know exactly what years the 9-160 sets were in production; but, the earliest ones I've seen were from mid-late '79 and the newest was a console from '83. The earliest 9-181 set that I've seen was from '82 and the most recent was from around '86. The earliest 9-181 sets used the same tri-focus CRT that the earlier system 3's used. Then, they dropped the tri-focus tube and went to using a standard inline CRT like what everybody else was using and continued to use up until the end of the CRT era. IMO, the older tri-focus tubes had the best picture.

From what I've read, Zenith really didn't want you to repair those 9-160 boards to component level. As for me, I tried to fix them to component level whenever possible because I liked the idea of only spending a few dollars vs. spending $80+ on a new 9-160 module (the last ones I priced were over $80). When I first started working on them, they were around $54 exchange.