Fisher 700T Help Please

[shelly_d]

All:

I have a Fisher 700T that is need of some help. One of the channels is intermittent and the switching of inputs seems somewhat screwey to me. I need to get my hands on a schematic or manual for this puppy to actually start sorting out all the issues I'm having. At this time, I cannot even figure out what is or is not an issue in the input and switching on it.

I'm satisfied that outputs are fine and the driver circuits are now operating OK. (Found one loose wire that I re-soldered.) Any help with diagrams on this would be very much appreciated.

Thank you all.

Shelly_D

P.S. I'm a bit out of my depth here cause I normally do tubes, not solid state, but I suspect this thing has a number of wiring and connection issues as opposed to blown semiconductors.

Thanks

 

[tcdriver]

Have you given your Fisher switches a good cleaning with DeOxit? If not, that may solve all of the problems.

 

[shelly_d]

No I have not. I would expect that to help quite a bit, however the relationship of the switching on the front panels and the labeling of the jacks in the rear is confusingly different. Since I do not know the signal path through the inputs and switching path it is difficult to trace out where the problems might lie. Additionally, I may wind up spinning my wheels on something that is just an unusual switching arrangement rather then a real issue.

If I can see a layout (i.e. schematic) I could work out where I need to set the switches to trace a signal through the unit to try to isolate the issues(es).

Thanks for the thought.

 

[larryderouin]

The TWO FISHER Consoles I have had notoriously dirty pots, switches and had noise problems. Cleaned both of them with De-Oxit, and one is singing like a nightingale, the other showed a problem with the FM side.

Why try and trace a signal thru a dirty path??? The FIRST Thing you should do BEFORE troubleshooting is to CLEAN the hell out of the switches and the pots, so you DO have a CLEAN PATH, should you need to trace out a signal. Would you hook up a car battery to corroded terminals and expect the power to get to the car 100%??? I didn't think so.

Clean the switches and the pots, check it, and if it's still got the problem THEN trace it out knowing that the path is clear and clean electrically.

What is confusing you about the labeling on the rear jacks?? List them and we'll see if we can decipher them. Fisher was kinda eccentric with labeling terminology(east coast gentry/NEW YAWKER and all) and more than a few of us West coast kids had problems with it for a little bit. Once you get used to it, it makes sense.

Larry