TASCAM 644 midistudio service manual

Discussion in 'TASCAM DIY Repairs and Mods' started by rohmal, Oct 29, 2017.

  1. rohmal

    rohmal New Member

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    Dear Sir,
    I need to find a service manual for TASCAM 644 as my unit is not recording on any channel as well as not erasing any. Any help is warmly appreciated in this matter. Thank You all ahead. The record light comes on and keeps on blinking while the play is going on without erasing.
  2. John Mackenzie

    John Mackenzie New Member

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    Tascam 688 midistudio
    Is the 644 similar to a 688? I have a 688, and just waiting for a service manual from USA. Quite expensive , with postage to UK, but I hope it gives some test proceedures.
  3. John Mackenzie

    John Mackenzie New Member

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    Does your 644 still play back prerecorded tapes OK ? I am almost sure that when the record light is blinking, you are in "rehearsal mode", but not sure about that , as it has been a long time since using these machines. In that mode , you are not recording anything, just monitoring ,while creating a track, before actually going for the take. My 688 manual explains all this. Sorry if this is not relevant.
  4. rohmal

    rohmal New Member

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    Dear Sir John ,
    644 is 4 track and 688 is 8 track. May be the general setup is same. My 644 plays back on all 4 tracks. When input is given I can hear(monitor) through all 4 channels., but when put to record the record light blinks and play starts with no erase on all 4 channels and the previous recording I can hear when I press the output button. Also I can see the levels on 4 channels on LCD display. Thanks for the interest.
  5. rohmal

    rohmal New Member

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    My one plays back the pre-recorded tapes on all 4 channels. When put to record mode I can hear signal on all 4 channels. Record light comes on blinking and play also happens and I hear no erasing as my pre-recorded tape plays with the input signal from monitoring out and nothing is recorded also.

    I read Your Problem also.
    Did Sir John, If you check your power supply. It should have on pin 1 -0V, pin 2-+10V, pin 3-negative 10V and on pin 4-+7V. If all is OK and check when a pre-recorded tape is played you have LCD meter level display on it when OUTPUT button pressed for display. If all is OK your sound output is blown. In my unit 644 the out put IC's are BA6209 ( seperate for each channel). There may be a pre-amp also. If you open the unit You can visually see any burnt part as if it did smell before stopping. I have included a sketch of power supply socket on unit seeing from behind in to the unit. So when you check your power supply chord it should be mirrored (flip along horizontal axis). Contact me if You need any help more with the findings.Good Day to You.

    Attached Files:

    John Mackenzie likes this.
  6. John Mackenzie

    John Mackenzie New Member

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    hello again rohmal. I was discussing my problems with my 688 on Facebook with a friend today, when another of his friends came in to the conversation. He told me that he has exactly the same machine ( not working) stored in his fathers garage. He tells me that I can have it for spare parts ! amazing news. I hope that this is true, and that it has a different problem to mine. I should be able to get one of them working properly. please keep in touch about this.