TV color turning red

[qguy]

I have this Sony CRT tv, suddenly the color has a red hue, color adjustment does not help. Is this something that can easily/cheaply fixed ? The effect is that screen seems to be covered by red celophane

I have soldering and contact cleaner experience with vintage audio receivers

[zeno]

What is the model number KV????

73 Zeno

[qguy]

The model is KV25XBR

Thanks

[zeno]

OK I dont have a manual so a couple of things to check.
First turn the color level all the way down.
If it looks B&W then you have a color problem that will be deep.
If it is red you have a chance.
IMPORTANT if you pull the back take the speakers off 1st.
A newer XBR set had an exploding back, taking it off would cause
it to shatter. Be gentile with it.

Look at the CRT socket board. There are usually 3 controls
R, G, &B. Try turning the R down.
Also look for bad connections especially where there are 3
identical transistors. It can be a shorted CRT. LIGHTLY tapping
the tube neck will sometimes make it flash back to normal.
but so will a bad connection on the board.
Last thing you can try is swapping the 3 identical transistors.
If it turns a different color one of them is bad, you can take
it from there................
Beyond that it gets deep.
Good luck

73 Zeno

[qguy]

Thanks

cleaned the tube socket and soldered some cold solders on the tube socket. The red is now gone, but the TV needs some more brightness, I had to adjust the picture and brightness setting to full get acceptable brightness. The brightness trimmer on board is on full. Are there any other trimmers I can adjust to boost the brightness ?

Thanks again

[zeno]

Originally Posted by qguy

Thanks

cleaned the tube socket and soldered some cold solders on the tube socket. The red is now gone, but the TV needs some more brightness, I had to adjust the picture and brightness setting to full get acceptable brightness. The brightness trimmer on board is on full. Are there any other trimmers I can adjust to boost the brightness ?

Thanks again

Progress
Find the G-2 control. It may be the one you turned. I think it
was on the CRT skt on that set but may be on or near the HV transformer.
Its usually a fairly beefy control compaired to the others.
You will need a meter. Check the resistors going to it. They do
open. Basic set up is: one end of pot goes to apx 200 DVC
the other end goes to apx 800 VDC through a resistor.
Wiper goes to CRT G-2 pin & has 400-500 VDC on it.
Dont confuse with the H-STAT control !
When done turn up G-2 slowly til thin white lines
appear then back it off. Darken room & turn brightness down.
be sure there are no lines in pix and it either is black or very dim.
Good luck

73 Zeno

[qguy]

Thanks all the trimmers on the CRT socket board were all the same kind. I already closed the TV for now, I will look for that G-2 control trimmer

Thanks !!!