marantz MCD 810 cassette deck

[digitalscorpion]

MCD810. Good condition.
When I press play, the VU meters max out, with or without cassette loaded. The play head or pickup looks like it could have some gunk on it but not sure. I took some isopropyl to it and the meters are still maxed out. Can't seem to locate a service manual. Any thoughts?

[R_J]

Re: marantz MCD 810 cassette deck

do the meters go maximum if you place it in record mode? it might be a dirty record/playback switch.

[redwire]

Re: marantz MCD 810 cassette deck

Yes, a dirty record-play switch can make the circuit oscillate. Common in cassette decks.
Best to take it apart and put contact cleaner like DeOxit D5 in the really long switch (but not on the belts!). A trick in the shop was to take a small screwdriver and exercise the switch lever (inside the unit) 50 times or so, back and forth, to scrape off heavy oxide buildup.

Another method, without taking it apart, is pushing the no-record tab sensor up (using a junk cassette, or your finger or scotch tape), while pressing the record button a zillion times to exercise it. Not too rough.
If the deck has a motorized transport then this is not the best method.

[digitalscorpion]

Re: marantz MCD 810 cassette deck

When you say 'switch', you mean the actual mechanical play switch? I wouldn't think that would cause any audio disturbance, such as a turn/slide POT would..

[redwire]

Re: marantz MCD 810 cassette deck

The record-play switch is on the circuit board, not the front panel. It is a long multi-section switch with a spring or wire linking it mechanically to move when you press the record button on the front panel. Note the REC button won't move, it has a lockput, unless the tab is pushed up. With the door open, a pinky pushing up on the rec tab sensor, then I can push the REC button down.

Don't be too rough, just find a way to press and release the record button a dozen times and see if that helps the problem. Ultimately contact cleaner is best. Dirty rec/play switches are very common problem because they don't move for years and get oxidized. I've seen many decks oscillate and peg VU meters due to this.
I bought a 2252B in 1978 but went with the JVC KD-55 cassette deck. No idea what these Marantz decks are like.

[jons]

Re: marantz MCD 810 cassette deck

Hifiengine is first place to look for service manuals https://www.hifiengine.com/manual_li...z/mcd810.shtml