Talon2000
Well-known member
Initial problem..
Poor picture quality, and Horizontal was to wide. Aproximately 2 inches off screen on both sides.
Went to adjust the Horizontal coil and it was broken. Typical for these.
Replaced Coil, and was able to make horizontal smaller but screen was still to wide.
Did a cap kit, hoping that C511 might be the problem. Needed a cap kit anyway.
Well no change on the horizontal width, but picture looks much better.
Checked b+ to adjust, and found it was at 148V and not moving. Dang
Pulled X701 to see if I could get adjustment. Nope still 148V
Checked for cracks and cold solder joint. Nada this board actually looks pretty clean. I found only 1 bad solder joint.
Checked the voltage Case to ground on X01 148V
Checked the other end of R1 was 160V
So at this point, I start checking voltages on X901, and X902.
X901 B=148V C=160V E=148V
X902 B=.6V C=148V E=6.8V
Well those aren't right.. Looks like there is a problem with 900 circuit.
So I start checking the transistors, the appear to check good.
Then the Diodes.. Thinking surely it's D905 Nope it checks good too.
Checked resistors.. Aha!! R908 47K 2w open..
replace and check.
Well now my b+ is running at 174V still can't adjust.
I do measurements on X902 again, and still getting same readings. Pull and check it again on my BK520B still seems good. Had one handy so I replaced it.
Now my b+ is running at 109V. Fingers crossed I adjust. WOOHOO Set at 120V
Check Horizontal size, and adjust WOOHOO size came back in..
Ken mentioned to me, that sometimes transistors check fine out of circuit, but under load will fail. Hence the reason I did voltage checks. X902 wasn't turning on, and it feeds X901 which is why I was getting bad readings on it.
Hopefully this will help someone else.
Kevin
Poor picture quality, and Horizontal was to wide. Aproximately 2 inches off screen on both sides.
Went to adjust the Horizontal coil and it was broken. Typical for these.
Replaced Coil, and was able to make horizontal smaller but screen was still to wide.
Did a cap kit, hoping that C511 might be the problem. Needed a cap kit anyway.
Well no change on the horizontal width, but picture looks much better.
Checked b+ to adjust, and found it was at 148V and not moving. Dang
Pulled X701 to see if I could get adjustment. Nope still 148V
Checked for cracks and cold solder joint. Nada this board actually looks pretty clean. I found only 1 bad solder joint.
Checked the voltage Case to ground on X01 148V
Checked the other end of R1 was 160V
So at this point, I start checking voltages on X901, and X902.
X901 B=148V C=160V E=148V
X902 B=.6V C=148V E=6.8V
Well those aren't right.. Looks like there is a problem with 900 circuit.
So I start checking the transistors, the appear to check good.
Then the Diodes.. Thinking surely it's D905 Nope it checks good too.
Checked resistors.. Aha!! R908 47K 2w open..
replace and check.
Well now my b+ is running at 174V still can't adjust.
I do measurements on X902 again, and still getting same readings. Pull and check it again on my BK520B still seems good. Had one handy so I replaced it.
Now my b+ is running at 109V. Fingers crossed I adjust. WOOHOO Set at 120V
Check Horizontal size, and adjust WOOHOO size came back in..
Ken mentioned to me, that sometimes transistors check fine out of circuit, but under load will fail. Hence the reason I did voltage checks. X902 wasn't turning on, and it feeds X901 which is why I was getting bad readings on it.
Hopefully this will help someone else.
Kevin
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