Found a Sony Trinitron KV-1212

[zeno]

Originally Posted by rca2000

ANY Sony that uses a GCS is something to STAY AWAY from!! Unless you are into masochism...I do NOT think a KV-1212 does....but may be wrong. If you have the SLIGHTEST problem with horiz. drive..kiss the GCS good-bye INSTANTLY !!

On the same page.
Sony was a super arrogant company in the 70's. Independant parts
distributors were yet to come. If you called them & managed to get
the right person they treated you like dog doot. The shops that did them kept mum on how to deal with them. They were getting $120 to open one, a LOT of beer & smokes at the time. Most of the arrogance went away in the 80's, the parts dept in KC were great & the tech help became friendly. Of course it helped to be an ASC & true franchised dealer !
Anyhows avoid the bad ones & have a fist full of electrolytics for the good ones. Nuf sed.

73 Zeno

[Kamakiri]

Soon as I get some packing material rounded up, she'll be headed to Florida

[DaveWM]

great, now I can give back the one I have been holding hostage to my buddy.

I looked over the schematic, horz seemed pretty straight forward use of transistors.

[dieseljeep]

Originally Posted by DaveWM

great, now I can give back the one I have been holding hostage to my buddy.

I looked over the schematic, horz seemed pretty straight forward use of transistors.

The one I had, I found a few bad 'lytics in the PC correction circuit. that cured that problem.
Before you get too involved in the repairs, check the soldering around the horizontal drive circuit, the transformer and the driver transistor. Just disturbing those connections, can take out the horizontal output transistors.
The 2SC867's are rather hard to get, as they're matched and expensive.

[dieseljeep]

Originally Posted by zeno

The ones to avoid use the SG613 or SG603 gate controlled switch for
a hoz output, few shops would get near one. They were sold apx
'72-'77. Before that not to bad. After that about as easy as most sets.

73 Zeno

In a Sony of that vintage, I replaced the damper diode and the GCS, with ECG replacements. The repair lasted about an hour.
The only parts that would last were genuine Sony replacements.

[zeno]

Originally Posted by dieseljeep

In a Sony of that vintage, I replaced the damper diode and the GCS, with ECG replacements. The repair lasted about an hour.
The only parts that would last were genuine Sony replacements.

Yup the old top-hat dampers used to open intermitantly. Change them
all even if I was working on another stage. OEM only of course.

73 Zeno

[DaveWM]

so if I own of these I should get a couple spare transistors? I can keep I eye open for them.

[rca2000]

Can't you use 2SC 1308's---those should work fine...unless Sony did the ol' "specific ckt" that you MUST use OEM's for....

[DaveWM]

found its way to soggy central Florida today, arrived in good shape, nice pic but has the same pin cushion issue I found on the other. bad cap located, pulled tested bad, but of course I am out of 4.7 uf argh...

video soon.

Thanks again Tim.

[Kamakiri]

Glad it made it intact! Did the best I could with the packing I had available.....

[DaveWM]

Yep and replacement caps are on the way, really only needs that 4.7 but I got a bunch of others as long as I was making an order. will get some fresh video as soon as I get it going. Now I can give back the one I fixed for a buddy, I liked it so much I was keeping it hostage

[Kamakiri]

I watched your video

As long as you guys want these types of sets, I'll keep grabbing them. Seems I always come across them in these parts. Nice thing is that they're very shippable.

[DaveWM]

LOL yea I dropped my buddies name in there followed with a hehehehe

I have been ducking him for a while hehehe

you are doing a good service, thanks again

even sets that are beat to heck are worth saving, as my buddy John Folsom told me a long time ago, its all about the parts.

[walterbeers]

Yea, beware of those sets with the SG613s. I had a KV1722 that was working on that lost the filament voltage to the CRT. Traced it down, found an open primary on the filament transformer. Thought this will be an easy fix. I put the circuit boards back in place, checked it all over, powered it up and poof, smoke. Guess what, both SG613s the Horizontal output and regulator SG613 are shorted. One more Sony bit the dust.

[Sandy G]

I'd ALWAYS be interested in the SMALLER Trinitrons-The 5", & the 3.7" models.. I just wish I had my 7010UA back, too, but its GONE..