Sony help...

[radiotvnut]

When you say the set has HV, I assume you mean to the CRT. Can you feel static on the screen when you turn it on?

Every time I've seen one or both of the 2sc4834's shorted, the set was dead and the resistor was open.

It could be that there is too much B+, triggering the shutdown circuit. I think the B+ should be 130 volts or so.

[freakaftr8]

Yes there is HV, static on the screen.. Ill try to measure the b+, if it is high, what should I look for?

[radiotvnut]

I've never seen high B+ on these sets. If it's high, I'd poke around the power supply board. One other thing, the standby light will blink a certain number of times when a newer Sony shuts down. The number of blinks indicates what fault is causing the problem (overcurrent shutdown, vertical sweep failure, etc).

[freakaftr8]

This one's not shutting down, just continuous standby. Think I might have shorted something, I just found the black wire for the grounding of the Degausing field touching the "A" board shielding! Yipes!

[freakaftr8]

And in that graceful event it seems that it might have taken out the vertical output IC, this is a 3 pole that has a heat syns that is mounted next to the plug in jungle board which I think is called the "A" board? Well the degausing coil might have unloaded onto the Vertical IC heat sync and the reason I think this is it is that thwe 6.3 ohm resistor that is in circuit with that IC gets extremely hot while the set is powered up for about 20 seconds and it's sitting in standby..

[kx250rider]

If the vertical IC failed, the set would kill the video. I haven't really found any vertical problems in those sets, so I don't have a good mental picture of it the way I do with the power supply and high voltage areas.

As RadioTVnut said, the standby light will blink a code to tell what the nature of the shutdown is. Unplug the set, wait a minute or 2, plug it back in, press power once, and count the number of blinks in each set. I don't have a manual anymore, but I think vertical collapse may be 7 blinks? DON'T count on that! It's only a faded memory.

Charles

[freakaftr8]

That makes sense, I know the sony blink code, this one is not giving a code, just a continious blink, like when you power it up, the blinking and accociated HV and audio, I can even see some light in the screen with the lights off representing HV, but it will not come out of standby, and the audio and HV never go dead, it will sit there with HV and audio forever probably.

[andy]

What happens if you turn up the screen control? This should over bias the CRT so that you can see something on the screen even if it's blanked. If you have a full raster, then you know it's not a vertical problem. The fast that it has HV makes me think this might be an unrelated problem. I've never seen a bad HOT do any other damage than to the power supply (which has to be working for it to have HV).

[freakaftr8]

Well the resistor that gets hot is coming off the vetrical frequency IC that I believe the wire touched. This IC is a 3 pole and looks like a transistor except it uses a metal base to connect the screw to the heat sync. If I crank up the G2 I get a white raster while the set is in standby.

[kx250rider]

If it's a full raster, then the vertical isn't the issue... Be sure to set the G2 back to exactly where it was, or a little lower if in doubt. Otherwise, the video won't pop on in those sets.

Is there any display on the screen when you push the volume, and is there any sound?

One thing that sometimes gets me is that the small interconnect plugs from the CRT board to the main board can get partially pulled out, so you might double-check those. If nothing, then it might be time to troubleshoot the video circuit.

Or if you want to make the set work, you could cheat, and just get another chassis for it. I bet my friend in West LA has a dozen of those sets working, but with a dim tube.

Charles

[freakaftr8]

Hmmm, that might be interesting.. You know this set really aint worth anything, but just one of those satisfied feelings that your giving a set to someone in need that you fixed. As for the video, there is no osd at all, the remote will control volume and channel as well as everything else, just no raster.
The stupid mistake I made was having the black wire that goes from the Degausing field unplugged from the crt neck board, and it touched the metal frame that goes around the big IC on the "M" board (I believe it's called) (the one that stands up from the mainboard).

[radiotvnut]

That black wire from the degaussing shield to the CRT socket is the aquadag ground lead. It must be connected when the set is on. Otherwise, a charge will build up and it will arc to whatever. There's no telling what it fried. You may be better off to find a chassis out of a set with a bad CRT.

[freakaftr8]

Well I give up on this POS! If anyone has a spare chassis, my set is a KV-27V10 from Sep 1994, the chassis is fried. Thanks!

[kx250rider]

Let me see if I can find one at the shop in West LA... I probably will go down there between this Thursday and next Wednesday.

Charles

[freakaftr8]

Awesome, thanks charles! I would normally give up on this thing and send it on it's merry way to tv heaven, but the CRT is excellent and the case is still great