Fisher CR-110 Cassette Deck problem

[NickatNight]

I have had this Fisher CR-110 cassette deck for quite awhile. All of a sudden, it starts playing louder in the left channel. Tapes that used to play normally now play louder in the left channel. I taped a 1 khz note off of youtube using a BIC T2M cassette deck. I adjusting the vu meters so that they are even at 0 vu while recording. I then played the tape back on the BIC, and the vu meters were even at about 0 vu. Next, I played the tape back on the Fisher, and the left channed is significantly louder. I've cleaned and demagnitized the heads. Anybody got any ideas on this? I have some experience with discrete circuits but not a lot with IC's. I do have the repair manual for the Fisher.
Thanks,
Nickatnight

 

[(*steve*)]

Does the volume control affect both channels?

 

[NickatNight]

It doesn't have a volume control, it's just a cassette deck. Tapes that were previously recorded and played okay now play louder in the left channel. All cassettes were recorded as close as I could get at 0 VU. Now, when I play them back, the left channel is louder and the meter shows close to +3 on the VU meter.
Thanks,
Nick

 

[shrtrnd]

Seriously clean the tape heads, and transport rollers. Odds are, they need cleaning.. I know you said you cleaned them, ...Hoping it's not one of the heads themselves going bad. Other problem I've seen a lot of, is the switching mechanism for forward and reverse needing cleaning. When they get dirty, one channel plays at a reduced volume over the other. Just some things to check, before you get into the circuit. (NOT the push-button on the faceplate, ....the mechanical assy at the tape heads).

 

[Resqueline]

It's a very strange fault indeed; that it's stronger than it used to be on one channel.. The only explanation I can come up with for such a fault is as follows:
If you lately rarely have used it for recording then I'd suggest that it's the long rec./playback changeover switch on the main pcb that has developed an oxide layer.
It's usually operated by a wire from the tape mechanism. Try to get some contact spray into it and operate it manually a couple dozen times (without power of course).

 

[NickatNight]

It's a very strange fault indeed; that it's stronger than it used to be on one channel.. The only explanation I can come up with for such a fault is as follows:
If you lately rarely have used it for recording then I'd suggest that it's the long rec./playback changeover switch on the main pcb that has developed an oxide layer.
It's usually operated by a wire from the tape mechanism. Try to get some contact spray into it and operate it manually a couple dozen times (without power of course).

This sounds like a good bet. I'll be working on this over the weekend and let you know. Thanks for your kind assist.
Nick

 

[NickatNight]

Okay, I cleaned the slider switch with an electronics cleaner but still have the same problem. I know it's in the playback circuit because I recorded something from a mono source and had the vu meters both at 0 vu. However, when I played back the same recording, the right channel was lower than the left. I will continue researching this and post what I found out, when I can. Thanks all for your assistance. I appreciate it.
Nickatnight.

 

[jerryg50]

I have had this Fisher CR-110 cassette deck for quite awhile. All of a sudden, it starts playing louder in the left channel. Tapes that used to play normally now play louder in the left channel. I taped a 1 khz note off of youtube using a BIC T2M cassette deck. I adjusting the vu meters so that they are even at 0 vu while recording. I then played the tape back on the BIC, and the vu meters were even at about 0 vu. Next, I played the tape back on the Fisher, and the left channed is significantly louder. I've cleaned and demagnitized the heads. Anybody got any ideas on this? I have some experience with discrete circuits but not a lot with IC's. I do have the repair manual for the Fisher.
Thanks,
Nickatnight

You must first set the playback levels to proper reference using a calibrated reference alignment tape.

Using an audio generator, you must set the record levels to match up so that when you play back the recorded signal, it comes out at the proper levels when played back. On most home audio tape machines 400 Hz is a good frequency to use for level reference.

See if you can buy the service manual for your tape deck. They will give you the full procedure that is required. It's better than working generically.

Jerry G.