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Old 9th Aug 2022, 12:57 pm   #27
ButchJames
Tetrode
 
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Join Date: Dec 2021
Location: Newcastle Under Lyme, Staffordshire, UK.
Posts: 84
Default Re: Sony TC-645 1/4 Track R2R Erase Head & Issues

Just replaced the motor run capacitors - the bonus now is that the capstan motor runs only luke warm. The removed caps were dated '1974', other unrelated caps are dated '1973'!? Will replace later.

I lubricated the motors a few days ago.

Very pleased so far with machine's progress.

My only criticisms of the TC-645 so far are:

(1) FF/RW => leftmost erase head wearing?
(2) The slightly crude method to drive the capstan, ie the idler method.
(3) No obvious way to disengage the spools so that the tape can be moved back and forth freely? Similar to that found on the Revox and others.

I'm still new to this machine, so obviously I've much to learn about it.

@Timtape: Thank you for your feedback. Yes indeed, the clue was in the double worn paths. However, I would still have re-capped and transitorised the bias osc circuit and studied related working voltages in that particular path chain, so no time was wasted in my opinion.
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