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05-05-2024, 03:47 PM
themaster1 themaster1 is offline
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Looks like i've saved yet another vcr (belt+ mode switch cleaning) but i've got a parasited output.

I haven't check the inside of the drum, though there are 2 long springs in contact with the lower drum on the Mobo. I checked all screws, everyting is in contact with the chassis real tight.
Checked the ribbon cables, well inside their sockets.Heads cleaned, gears greased.

The Blue screen (No OSD advanced Menu for this vcr) looks like crap aswell (i checked my cables / scart adapter not the issue)

My theory for now:
- Bad grounding of the scart (the two scarts, really?)
- Something inside the drum parasiting
- Capacitor(s) to change

Is there an easy way to test the grounding of the scarts ?

Ideas welcome (video sample below)

-- merged --

Well, after more investigation, it turns out NTSC tapes (SP only, EP plays like crap) play properly parasites-free, only pal-secam tapes affected (and Menu). I'm open to suggestions.

video link: https://we.tl/t-fpODxRvjc4?utm_campa...trk=TRN_TDL_05

service manual:

-- merged --

Page 25 of the service manual there is the schematic diagram of the MB. Should i suspect a bad capacitor surrounding the video processing IC chip (IC 301 LA 71598HM) ? Please note this electric stuff is not my forté.

Attached Images
File Type: jpg aiwa-magneto-face_avant2.jpg (50.2 KB, 14 downloads)
File Type: jpg aiwa-photo3-mode_switch-gros_plan.jpg (92.3 KB, 13 downloads)
File Type: jpg aiwa-photo2-mech.jpg (50.5 KB, 15 downloads)
Attached Files
File Type: avi AIWA-capture-test-bruit-easy_rider-Secam-parasites-HUFF.avi (84.14 MB, 1 downloads)
File Type: pdf AIWA-hvfx7800-Service_Manual.pdf (11.88 MB, 0 downloads)
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05-14-2024, 02:00 AM
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lordsmurf lordsmurf is online now
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I have nothing to add here, but didn't want you to think you're just replying to yourself here.

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05-17-2024, 02:38 PM
themaster1 themaster1 is offline
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Some update. I did resolder the pins of the scarts but it didn't improve. I couldn't open the upper drum, i'm missing the right hex key for now. Maybe i'll try a full drum swap if i can find one that fits. To be continued
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