Busted Sony 1210 Fixed!!

[Eric H]

Are the 2SC267's the ones on the bottom of the HV cage?
There's another large transistor mounted on a large heat sink at the top of the frame, I was guessing that's the Vertical?

Can I test them with the Diode range on my meter?

Lots of Electrolytics in this set too, lots of possibilities for failure here.

It looks like a nightmare to work on, very packed.

I don't suppose anyone has a schematic for this already scanned?

[ChrisW6ATV]

Originally Posted by Eric H

I don't suppose anyone has a schematic for this already scanned?

I have an original Sony manual for the KV-1201 and some others, but not for the KV-1200/1210.

[DavGoodlin]

Originally Posted by ChrisW6ATV

I have an original Sony manual for the KV-1201 and some others, but not for the KV-1200/1210.

I have two TAB "Japanese Color TV service manual" volumes that cover the KV1200 and KV1201/12, since I have had a KV1210 for 30+ years I forget but I bleeve I had this problem. It sounds like you're on the right track. PM me If you want a scan emailed.

[Eric H]

Originally Posted by DavGoodlin

I have two TAB "Japanese Color TV service manual" volumes that cover the KV1200 and KV1201/12, since I have had a KV1210 for 30+ years I forget but I bleeve I had this problem. It sounds like you're on the right track. PM me If you want a scan emailed.

Thank you for the offer, lets wait and see what happens when I put the new Transistor in.

I replace the three electrolytics on the Osc board and fired it up with the Transistor removed to see what would happen, without the transistor in place I still get just a vertical line but it's now bright white and perfectly straight up and down, and it fills the entire height of the screen, the oscillator is clearly heard running.

I put the transistor back in just in case I had misread the Ohms readings but it still doesn't sweep, it does however reduce the brightness and make the line green and bendy so it's probably dragging the power supply down I would guess, the surprising thing is nothing smokes or pops with this shorted power transistor in place.
Hopefully I will get the replacement next week sometime.

Kind of an odd set that has the HV circuit separate from the H sweep, it's like some of the vintage sets that used an RF high voltage supply.

I have a sweep transistor in an old Panasonic 5" Pop Up set but it's rated at 50w where the one in the Sony is rated at 125w, it might last a few seconds if I packed it in Ice before I powered it up.