Okay, this one was given to me by a neighbor and the plan was to have it replace a Sharp 32" flat CRT with a very weak picture tube. The sony was working fine upon receipt, if not a tad fuzzy. (adjust flyback) I opened it to clean it out, and removed and replaced the CRT board to clean it. When I powered the set back on, the screen blanked once and when it came back up, the picture was horribly dark, very out of focus, and discolored. :wtf: The standby led is also flashing five blinks, which I have never seen happen with a set up and running. Occasionally, the screen goes blue with lines that look like what usually appears when the G2 on the flyback is turned up way too high. After several minutes of operation, the screen goes darker and darker, until it is almost black. The blinking LED persists after I turn the set off. I am very confused... :headscrat

Since all you did was R&R the CRT board, check the solder connections on the CRT board, sounds like you might not have some bad connections, very common on Sony.

A few things to look at
Be sure you didnt crack the PCB at FBT.
Check that no harmonica connectors are crooked.
See if fillament is dimming with pix.
Check the G-2 & focus wires are not pulling out of FBT.

Odds are you stirred up a bad PC con moving things around.
Look especially under FBT & the CRT socket. You can find the
blink codes on the internet but IIRC they only come if the
set goes into shut down mode. Makes no sense !

good luck & keep us posted

73 Zeno:smoke:

Decided to revisit this set, and now it's doing something I have never seen before. When I power it on, degauss followed by a second of HV - with what appears to be bright ionizing inside the neck of the CRT! The TV tries three or four times to start, showing that ionizing for about one second each time. I unplugged it after the fourth try, as I didn't want to break anything! Photos to follow.

In the dark:

That tube has gone gassy. Possibly it cracked around a pin when you removed the CRT board?

Pull the board off again and see if any of the base pins have pulled out.

...

No no no no NO! I hadn't even thought of that! None of the pins came out when I removed the board again, but there could be crack(s) I didn't see. Two big TVs gone in a month! This sucks... :sigh:

No no no no NO! I hadn't even thought of that! None of the pins came out when I removed the board again, but there could be crack(s) I didn't see. Two big TVs gone in a month! This sucks... :sigh:

Sad! Now you have two of those big, heavy dogs to get rid off.
Sets like that seem to be around, at thrifts or CL. :scratch2:

I agree on a air leak in the picture tube...... But it must have been a quick inrush
for you not to have noticed it as you worked on it.....? No hissing sound while
working on that end of the tube....? No filaments lit right....?

.

it must have been a quick inrush
for you not to have noticed it as you worked on it.....? No hissing sound while
working on that end of the tube....? No filaments lit right....?


I'm thinking that it must have a *very slow* leak from a crack around a base pin.... the vacuum slowly degraded (no hissing) and the tube produced a dim out of focus picture for a while, until some arcing started to occur (blue flashing) *then* was observed to be gassy (purple glow in the gun). Tube is toast. :(

jr

Set worked fine when I got it. Removed and replaced CRT board while cleaning inside. After powering up, set had a dim and very fuzzy picture, eventually degrading to almost black/nothing. I left it alone for three months and tried it again yesterday, which is when the ionizing showed up. I had to have cracked the neck somewhere in the vicinity of the pins when I removed that board. X_X

...

It would have to be a very slow leak because if it was up to normal atmospheric pressure, it would just arc internally rather than glowing.

I assume that will happen after another few months...

My plan now is to put the entire set on CL for parts. If it doesn't get any nibbles, I'll pull the boards and parts, and junk the CRT and empty shell. Anyone here need parts from this model?