I've got this GE VG4025 (dont know chasis) that is having SMPS problems.
When plugged in, capstan pulsates at about 1hz. After about 3 minutes of
this, the display starts to flash POWER/VCR LEDs in sync with capstan
pulsing. I searched for VG4025 and got this webpage and content:
http://intrepid-video.com/database/genelectric.htm
VG4025(VR507)
*Dead
*C08 in power supply

*Dead, timer flashes, won't accept tape
*C09(22/16v np), C04(4.7/25v), C05(82/200v)

*At power on capstan pulsates
*C09(22/16v np), C4(4.7.25v)

I replaced C04, C09 and C05, however C05 is 400v (should work, right?)
No change in condition. I also noticed that if I manually turn the load
motor to a half-load position, the VCR will power up long enough to
"eject" the tape. If I hold it in place, it will eventually time out,
however now the VCR will work perfectly from a mechanical point. Loads,
Plays, rewinds, seeks, etc.
I stuck a tape in and noticed that it had problems syncronizing the
correct speed and sound would be garbled and slow. Picture also had 4
thin horizontal lines that would roll down. Also could hear motor noise
though speakers.
I dont have a ESR meter (yet!), but have heard that the caps in the
secondary need replacing too? Or is it a diode?
With power supply pulled out of machine, under no load, I am not getting
readings out of the xformer that are silkscreened on the board. Seems
that two of the primary windings are powered, but the windings connected
to the feedback circuit are not.
Any help please!
(hope this post was a good, detailed post)

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BFriedl
A+ Certified Technician
AIM: UACybercat
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