View Full Version : My really small Sony

01-30-2005, 10:04 PM
Here's my Sony KV-5100 that I just finished up. At 5" it has to be the smallest color TV of its day (early to mid 70s).

It's actually a combination of two sets. The first was from ebay and in really bad shape. It was missing the back and screen protector, was very dirty and someone hacked in their own power supply to replace the original switching power supply. The rear power and ant jacks had also been replaced and the whole thing had obviously been stored in a damp environment. It was cheap, so I took a chance on it. Fortunately, the CRT was good and the set actually still worked.

About a year later someone responded to a newsgroup post. He said he had a KV-5100 that had been dropped and sold it to me for the cost of shipping and a small amount to cover his trouble. This set was in good cosmetic condition, but the fall had cracked the exhaust tip of the CRT. That's where the good CRT from the junker came in. The set was also missing the antenna, but amazingly I was able to order one from Sony at a slightly inflated price, but not bad for a 30 year old set.

After some minor adjustment and a lot of cleaning it's looking pretty good. It has an excellent picture for such a small set.

The CRT is unusual because it uses directly heated cathodes. There are 3 filament transformers with the video signal applied to each heater. You can see the green filament on the broken CRT. Each filament is a tiny metal tape and the cathodes are metal discs welded to this tape.

The other thing I noticed while working on it was that the circuit board has locations for a pincushion correction circuit that wasn't used in this set. I wonder if any other product used the same circuit board and had the PCC circuit? As you can see from the picture, it does suffer from slight pincushion distortion.

I'm looking for a battery pack now.

Chad Hauris
01-31-2005, 09:27 AM
The directly heated CRT filament really has an instant-on quality...I have a small sony B/w set that is directly heated filament.