488 MKII won't record on track 8

Discussion in 'TASCAM Analog Forum' started by obZen, Jul 30, 2019.

  1. obZen

    obZen New Member

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    Gear:
    414MKII, 424MKII, 488MKII
    Before I say anything, yes the sync is off. The problem is simply that track 8 won't record. Channel 8 plays back just fine when I flip the tape (track 1 flipped) and I can also record through channel 8 onto other tracks. When I engage the machine for recording on track 8, both track 8 meter and the stereo mix meter light up. But it doesn't record. I don't think it's an issue with the sync switch because when it is on, track 8 meter doesn't show, but the stereo meter does. And when the sync is off, both meters light up.

    However, when I record 'nothing' to test the erase ability of track 8, it works perfectly fine. It erases what I had recorded on the flipped track 1. So I think the issue is isolated to the record ability of track 8. I cleaned the heads with 91% isopropyl and even though it was my first time, I think I did it it correctly.

    I opened up the machine and checked as well as reconnected all the connectors. One guy on another forum pointed out a specific 8 pin connector on a vertical PCB that could be the culprit, but I went through all of them anyway. He seems to think it's a faulty relay. I'm no electrical engineer but I have built EQ, compressor, and preamp kits. Those are more like Legos for audio nerds though and I don't have much knowledge of the deeper workings. My soldering technique ain't bad though!

    The other more minor issue is the headphone jack is scratchy and cuts out a bit when I move it around. Maybe it's a bad solder joint? I tried reconnecting the connector to the tiny headphone PCB but it didn't do anything.

    I'm quite amazed at the sound quality achieved by this machine... 8 tracks on an 1/8" cassette! I would love to get it working. Any ideas or advice?
    Last edited: Jul 30, 2019
  2. Jim D

    Jim D New Member

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    From:
    Drexel Hill Pa
    Gear:
    488 MKII, DP 24
    obZen have you considered a bad mic\line switch? I have that model and had an issue like yours with track 1. I replaced that switch and it worked perfectly. The switch can wear out over the years.
  3. obZen

    obZen New Member

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    Do you mean the 3 way switch at the very top of the channel (line/tape/multi mix)?
    Last edited: Jul 31, 2019
  4. Jim D

    Jim D New Member

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    Drexel Hill Pa
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    488 MKII, DP 24
    Correct
  5. wkrbee

    wkrbee Active Member

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    Broken sync.switch?
  6. -mjk-

    -mjk- Moderator Staff Member

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    From:
    Hukou Township, Hsinchu County, Taiwan
    Gear:
    DP-32, | 2A Mixer, A3440
    @obZen you may try touching up the solder joints on the board for that switch. Doesn't cost anything to try. Pressing on PB switches can put pressure on the PCB and stress-crack solder joints sometimes.