G07 No glow

Fudd

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got a go7 cbo with 140v b+ but no neck glow......what should i be checking the 900 series? i've gone thru most of them and they all check out..
 
140 is high but generally not high enough to be a problem in the 900's section of the board. Do you have new caps in this thing? The R908 resistor would be the only thing in this section that could be suspect but i've had these be bad with b+ readings in the high 150 range and still produce a picture
 
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yea i bought this from another klover who put a deluxe in it and couldn't get it working....there were lifted solder pads parts missing, etc.....i've replaced all the missing parts, reflowed the solder and nothing....145v at the b+ check but no glow or picture....r908 checks out good.
 
got it.....they started replacing resistors and r512 was replaced with a 80k resistor instead of a 8k.....i can now adjust the b+ to 120.....now to see what else is wrong..
 
possible vert deflection now? this looks slightly different from the failure i've seen before.
 

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Check FR401 supply voltage for X401 @ collector vert trans and X402
between the two trans is r420 a 5.6 ohm,check for open traces off the vert-trans
As always solder the pots/controls,and with monitor off, clean or
turn the controls back and forth a few times to clean the contacts
then return to spot you started. bad connections and open pots
can cause a few different symptoms..

I just had a G07-904 Hear HV for a second then nothing..
it went into shutdown,killing the Horiz-Drive..
Open fuse.. B+ good, I o-scoped HOT collector
could see messed up waveform at power up.
replaced fly,up and going now..
I use a regular o-scope with a 100 times probe
to measure waveforms on Collector of HOT..
If you monitor the waveform on any HOT you can tell
if the FLy is shorting inside,also a flyback ring tester..
Just sharing my experience,with this repair.

Good Luck!
 
i've got power to it....i just refowed a bunch of things and readjusted my b+....at 95v i get the skinny red line down the middle.....at 120v i get a thick about 6 inches running thru the middle...minor progress.
 
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