Repair: input channel on 4-track tape recorder.

Motivation:

Philadelphia musician/writer Jon Pfeffer sent me his Tascam 414 for repair when it’s Channel 1 was no longer recording.

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For starters, the devices switches and pots were FILTHY.. obviously this is getting some good use.

TO THE BENCH:

Process:

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First step is to get the face-plate off. After pulling pots and switch-heads, you also have to find the anchor screws that are hidden inside the cassette deck.
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be careful lifting the front-face off the transport buttons (play, rewind, etc).
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these little monsters are DENSE mixture of main PCB and wiring between daughterboards. The mechanical cassette has lots of wires to worry about carrying power, signal, motor, etc. Other than that, it’s a walk-man with 4 read and 4 play heads.
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in order to get to Channel 1, I had to remove this electro-magnetic shielding plate. This part was tricky.
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finally isolated the board to it’s channels. TIME to CLEAN !

 

 

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I checked continuity on the input hack (here upside down) and fond that it was not even making connection to the board. AHAH

 

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I found that the input jack had become loose, and needed to be re-aligned and re-soldered. Note the arrow in silver sharpie that points to the bent metal flange that’s supposed to hold the jack in place.
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VERY glad to have found the problem in only ONE dis-/re-assembly, without having to dive in multiple times.

Conclusion !

After re-assembly, I made this quick video:

 

to show that Channel 1 now…

  • passes input signal
  • records to track 1
  • plays back from track 1

…before returning to customer Jon Pfeffer

It was better to repair that replace, saving time, money, and waste.

 

Contact me if you have any line-level gear you nee warranty-voiding repair upon.

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