drh4683
06-09-2007, 09:38 AM
This is that little 14" I found at the estates last saterday. This was quite a dirty set when I found it, but could tell it had much potential. I went all the way on this one and took the entire set apart to clean.
It was from a non smoker home, but had its fair share of dirt in on the cabinet and on the knobs.
The little 12B8C15 hybrid chassis was neat to see out of its cabinet. They didn't get any smaller and more comact than this for a zenith tube color set.
It was a well used set, was in for service a number of times. Some of the problems found by me from other techs: Broken off solder cone on one of the B+ junctions, the tech bunched all the wires up and soldered them together. I removed a solder cone from a parts chassis and properly resoldered the B+ leads back how they should be. Horizonal output cathode fuse was run up to the top of the chassis for easier replacement and tacked to ground. The chassis indicates that the fuse is under the set. You could see where the orignal leads from the fuse were clipped. I reinstalled it in its correct position.
UHF tuner didnt work, due to dirty wiper springs.
10Z10 audio output was bad as usual, as well as the typical faulty 2HA5 and 4GJ7.
Another reason the set HAD to be dissassembled was the fact that the color and hue controls needed to be cleaned and there was absolutly no way to get at the pots on this set unless the chassis was pulled! The opening of the pots were facing down on top of it, so you couldn't even get them from a distance.
This set uses the 2 pole static convergence unit. Much simpler convergence circuit. The convergence board is only a 3 pin connector!
As for cleaning, I used fantastic with water, which cleaned up excellent and does not leave marks or dull the cabinet if used properly. Never apply a cleaner directly to a plastic cabinet from the spray. 9 times out of 10 you will stain the cabinet with "spray" marks. Also, never use a toothbrush other than to clean corners and the speaker grill, otherwise you will scuff the reflective finish on the cabinet. I learned that long ago. The only way to really clean a TV and make it look good is to take the entire thing apart so you can really clean using water and a toothbrush, not having to fear getting things wet like the speaker etc. You can clean it up nice and rinse it down with water to get all the junk out of the corners. I do not rinse the back cover off with water as it will ruin the tags and labels.
With the set having as much use as it seems to have had, the CRT is excellent still.
Even though this set has the bandswitch tuner, it still makes makes the loud "clunk" noise when tuned. This is the last year zenith used the bandswitch tuner with the leaf spring on a steel ball the indented steel channel stop wheel. If you know zenith, later on they used the cheaper metal leaf spring on a plastic stop wheel, making the tuner feel much "cheaper" when tuned.
Again, the model chassis tag was still on back of the set which is amazing for these portable sets. Starting in 1971 zenith switched from the chassis model stamp to cheaper paper tag with red lettering which seems to always have faded out unless the TV was in the dark for the past 35 years.
If you really want to know what model you have, use a black light and shine it on the tag, you can then read the info on the tag! It works good too.
The TV is now reassembled and works great. Looks like a whole other set compared to when I first got it.
It was from a non smoker home, but had its fair share of dirt in on the cabinet and on the knobs.
The little 12B8C15 hybrid chassis was neat to see out of its cabinet. They didn't get any smaller and more comact than this for a zenith tube color set.
It was a well used set, was in for service a number of times. Some of the problems found by me from other techs: Broken off solder cone on one of the B+ junctions, the tech bunched all the wires up and soldered them together. I removed a solder cone from a parts chassis and properly resoldered the B+ leads back how they should be. Horizonal output cathode fuse was run up to the top of the chassis for easier replacement and tacked to ground. The chassis indicates that the fuse is under the set. You could see where the orignal leads from the fuse were clipped. I reinstalled it in its correct position.
UHF tuner didnt work, due to dirty wiper springs.
10Z10 audio output was bad as usual, as well as the typical faulty 2HA5 and 4GJ7.
Another reason the set HAD to be dissassembled was the fact that the color and hue controls needed to be cleaned and there was absolutly no way to get at the pots on this set unless the chassis was pulled! The opening of the pots were facing down on top of it, so you couldn't even get them from a distance.
This set uses the 2 pole static convergence unit. Much simpler convergence circuit. The convergence board is only a 3 pin connector!
As for cleaning, I used fantastic with water, which cleaned up excellent and does not leave marks or dull the cabinet if used properly. Never apply a cleaner directly to a plastic cabinet from the spray. 9 times out of 10 you will stain the cabinet with "spray" marks. Also, never use a toothbrush other than to clean corners and the speaker grill, otherwise you will scuff the reflective finish on the cabinet. I learned that long ago. The only way to really clean a TV and make it look good is to take the entire thing apart so you can really clean using water and a toothbrush, not having to fear getting things wet like the speaker etc. You can clean it up nice and rinse it down with water to get all the junk out of the corners. I do not rinse the back cover off with water as it will ruin the tags and labels.
With the set having as much use as it seems to have had, the CRT is excellent still.
Even though this set has the bandswitch tuner, it still makes makes the loud "clunk" noise when tuned. This is the last year zenith used the bandswitch tuner with the leaf spring on a steel ball the indented steel channel stop wheel. If you know zenith, later on they used the cheaper metal leaf spring on a plastic stop wheel, making the tuner feel much "cheaper" when tuned.
Again, the model chassis tag was still on back of the set which is amazing for these portable sets. Starting in 1971 zenith switched from the chassis model stamp to cheaper paper tag with red lettering which seems to always have faded out unless the TV was in the dark for the past 35 years.
If you really want to know what model you have, use a black light and shine it on the tag, you can then read the info on the tag! It works good too.
The TV is now reassembled and works great. Looks like a whole other set compared to when I first got it.