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Revox A700 F6 fuse blowing


I have a nice Revox A700. last time I used it it worked fine. It sat for several years (5-6) and when I tried to use it- all the tape controls were lit and I knew something wasn't right. I removed the back cover and found the F6 fuse blown. I replaced it, but it blew instantly upon pushing the power button. Can someone help me with a clue or two?
Thanks, Kurt

Re: Revox A700 F6 fuse blowing


This is a blown capacitor 2200uF (FRAKO), C24 plus blown rectifier, D6 on Board.1.067.160 or 161.

Replace all 4 2200uF (FRAKO capacitors ) on ths board plus recifier D6 (by a stronger one e.g. B100C1000).



Re: Revox A700 F6 fuse blowing

Thanks for the reply. I wrote in a while back. since then I found that a couple chassis screws were missing? maybe vibrated lose? I shook the machine upside down and low and behold a screw fell out. And my arms were dead. I then tried the unit and it seemed to operate of, except no I have a Humm coming thru the audio path that was not there before. Any ideas where I should look? I cant use the Revox because of it. It was my dads unit and I love it and want to keep it working.
Thanks Mart.

Re: Revox A700 F6 fuse blowing

Dont put it to the AC powerline ! Its just those 40 years old electrolytic capacitors. All them off and fresh ones in !

Re: Revox A700 F6 fuse blowing

What about the F7 fuse blowing, same thing? I just replaced all the X2 caps. All transport lights are on and the machine runs in Play I think fast. Help!