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Greetings.
I've got a Panasonic NV-HS65 (AG-3520) Japan only deck that uses VU meters instead of VFD for sound level monitoring.
It had numerous issues, most of which are fixed (the usual replacement of SMD caps deal on Y/C and HQ boards, repair and recap of a bad PSU that was most likely used with 220V or hit by lightning, most of the boards getting recapped etc.), but the ones that still persist are strange, and unfortunately i was not able to trace what causes them.
1) When the unit is turned on, white streaks and sync ripple appear on video whenever timer VFD is lit up.
White streaks fade in a few seconds but the sync ripple does not. Disconnecting timer board's 3-pin power? cable makes these disappear. (the unit has a separate board mounted below which seems to handle a portion the power distribution among the boards)
2) VU meters stop working after some time on playback.
This unit has a separate board for the audio power supply, which uses a linear transformer. I found out that this is caused by mute pin of the BA6138 VU meter driver circuit gradually building up voltage, indefinitely, but i was not able to find the cause.
Minor issues include silent noise in headphones whenever drum or mechanism motors run, but these don't really seem to be related.
I am writing this in hope of someone encountering and solving similar problems on similar machines and say thanks in advance. Really don't want to get rid of this machine despite the amount of headaches it has already caused.
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