Technics 1506 Recording

[Grantola]

Hello All,

Don't know a whole lot about these machines, but I do know I've recorded on this unit previously so it did work fine at some point, and I didn't 'adjust' anything. After a year of hardly much use, I tried to record and noticed a problem. Playback is missing the right channel (it isn't totally missing, but it's extremely low sand muffled). When I record with the monitor switch flipped to source, everything sounds fine, both channels read similar decible levels, etc. When I flip the monitor switch to tape during recording, that's when the right channel drops out. Whether I record with the monitor on source or tape, all I get is a left channel signal when I rewind and play back. Frustrating.

The only fix I tried doing was removing the head block and spraying contact cleaner in the 2-track/4-track switch and rocking it a few times. That didn't do the trick

ANY thoughts here?

It's almost like the record head got out of alignment somehow and now won't record the right channel. But again, I haven't touched it since successfully recording previously, so I doubt that's it.

Other tapes I have play both channels just fine, so I know the 4-track playback head is good

 

[dhnash]

This problem could be caused by oxide build-up on the record head in the area where the right channel gap is located. You should check this carefully and make sure the record head as well as other heads are spotlessly clean. Another possible cause is poor contact in the right channel record mode switch. This switch has two sets of contacts, one set that connects the bias signal to the right channel erase head and a second set that connects the right channel audio and a lower level of bias signal to the right channel record head. You might try cleaning this switch with DeoxIT if you can access it. The switch I am referring to is the leftmost one in the attached photograph. It may be necessary to remove the control knobs, lever switch covers and lower front panel in order to do this. I agree that record head alignment is not a likely cause for this problem and you should avoid making any adjustments to its position.