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Akai 635d reel to reel vu lights only, no other power?

Purchased this unit new while overseas. It was unused for years, then I began using it. It really worked great for long time. The only problem I had was getting past the cheep ampex tapes which really gummed up the heads. I may have encountered a power surge, but recently I went to turn it on, the VU lights lit up as normal, but the there were no power to the rest of the machine. All fuses were tested and were good. Any Thoughts as to what went wrong?

If by chance it blew a connecting capacitor between blocks, is their a source to get these vintage parts for these great machines?

Thanks



Re: Akai 635d reel to reel vu lights only, no other power?

Hello
These old machines often have problems with the capacitors of the logic control board and the motor control card capstan.
It makes sense to change all chemical capacitors of these two cards, as well as check the control transistor motor circuit and the diode bridge.

Good luck to you
Sorry my English is not very good !!!

Re: Akai 635d reel to reel vu lights only, no other power?

Thanks a lot for your help. I found one large capacitor (470 160volt which is the largest capacitor on the board), to be non responsive to the multi-meter. I found a source to replace this part, will let you know what happens. Thanks again.

yashoda rohana's picture

Re: Akai 635d reel to reel vu lights only, no other power?

One of my friends had an Akai GX-635D, he stopped using it for a few years and then wanted to make some recordings on some new tape he got and he had the same problem the machine powers up but doesn't run (no relay sounds even) he traced the problem and it was a bad capacitor on the board. I think it's one of the capacitors. To make sure that the problem is in the main board or the control side you can power up the unit and send an input signal then check the vu meters and check whether you can hear the sound of the source you input.

Good Luck!!!!

Re: Akai 635d reel to reel vu lights only, no other power?

Thanks a lot for your help. I found one large capacitor (470 160volt which is the largest capacitor on the board), to be non responsive to the multi-meter. I found a source to replace this part, will let you know what happens. Thanks again.

Re: Akai 635d reel to reel vu lights only, no other power?

Hi, I know I am responding late to this thread but have you or anyone managed to get their 635 running?

I have purchased and cleaned up a used unit but same as others, not running and only VU meters lighting up.

Is there a clear and precise list of all capacitors required for the control board as willing to accept a challenge of replacing them all but need advice on quality types needed etc.

Thanks