National NV-H65 Hifi Audio Tracking Prob

[Ren]

Hi there..

I have a National NV-H65 Hifi Stereo VCR.. (shes an oldy, but still going
Strong)
When playing back Pre Recorded Tapes i get a crackling popping HiFi Audio
sound.
This is with the Tracking set in the Central position, which gives best
picture Quality Tracking.
If i adjust the Tracking to the Negative slightly, then the Hifi Audio
sounds Normal, without the Popping and Crackling, But the Video picture
shows the Normal Noise bars, as it does when the Tracking is not set
corrctly..

Does anyone have any Ideas for a fix ?.
I was thinking possibly the Spool tension ?..

Anyway.. I'm open for any contribution..

Thanks

Ren
New Zealand.

 

[Bob Parker]

Hi Ren,
Have you replaced all the low voltage electrolytic caps in the
power supply yet? After all this time, the originals are likely to be
very sick and might have something to do with this fault. This is a
design problem with that series of VCRs.

Bob

Hi there..

I have a National NV-H65 Hifi Stereo VCR.. (shes an oldy, but still going
Strong)
When playing back Pre Recorded Tapes i get a crackling popping HiFi Audio
sound.
This is with the Tracking set in the Central position, which gives best
picture Quality Tracking.
If i adjust the Tracking to the Negative slightly, then the Hifi Audio
sounds Normal, without the Popping and Crackling, But the Video picture
shows the Normal Noise bars, as it does when the Tracking is not set
corrctly..

Does anyone have any Ideas for a fix ?.
I was thinking possibly the Spool tension ?..

Anyway.. I'm open for any contribution..

Thanks

Ren
New Zealand.

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[Ren]

Hi Bob..

Yes.. I have gone through and replaced all electrolytics in the main power
supply, aswell as a 10uf Cap on the Main Servo Board.(This was causing the
Counter and Tracking to play up)
I had to do the power supply over as i was also getting blue Crosshair
interferance on playback.
All is Fine now.. Video playback is perfect.
Just the sound tracking is just slightly out.

Cheers

Ren.
Nz..

 

[Phil Allison]

Hi there..

I have a National NV-H65 Hifi Stereo VCR.. (shes an oldy, but still going
Strong) When playing back Pre Recorded Tapes i get a crackling popping HiFi Audio
sound.
This is with the Tracking set in the Central position, which gives best
picture Quality Tracking.
If i adjust the Tracking to the Negative slightly, then the Hifi Audio
sounds Normal, without the Popping and Crackling, But the Video picture
shows the Normal Noise bars, as it does when the Tracking is not set
corrctly..

Does anyone have any Ideas for a fix ?.
I was thinking possibly the Spool tension ?..

** Hi-fi sound and picture information occupy EXACTLY the same areas of
tape. With VHS hi-fi the recording is on the tape * underneath * the
picture info. With Beta hi-fi it is recorded in the same area but in a
different frequency range to the video. I suspect worn heads is the
problem.



............. Phil

 

[Ren]

Thanks Bob , Phill and Allan


I have it sorted now. All is Fine.
Yes.. I did replace that Infamous 10uf Cap that is located on the servo
board.
What actually caused the Hifi Audio tracking problem was the Tape Alignment
to the Video Drum Assembly.
I ended up slightly tweaking the Tape Take up Arm on the side of the Erase
Head.
I would have adjusted it by not even 1/4 of a turn.
This instantly re-instated the Hifi Tracking, and didnt effect the Video
reproduction. (however, by going an extra 1/4 of a turn, then the Video did
deteriorate)
I ran the Deck all day yesterday, changing tapes quite often, and didnt
encounter a problem..

Allan, I tried looking for a Audio Tracking adjustment, but didnt have much
luck.
Id probaly require a servive manual to find it.
The only tracking adjustment available is the One Adjustment that does
both..

Although this VCR is just a standard Hifi Stereo Deck ( Non Nicam) and is
probably nearing the 14 years mark, i find that it still keeps well and
truely up wiith my Sony SLVX 810, which is also regarded at quite a good
unit in its day.

Thanks for your help..

Cheers


Ren