• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

MCS 3865 Needles stuck!?

Big15Inch

Big15Inch

New Member
I bought a MCS 3865, MCS 3701, and MCS 3564 amp, tuner, and tape deck, respectively, and all the needles (VU) seem to be pegged like this thing went through a power surge....What do? I've taken it somewhat apart and sprayed it with electronics cleaner but the needles in the amp still are stuck, they vibrate very little at the every top but its not a full sweep like it should be...any suggestions/places I can get replacements?
 
Register to hide this ad
Some cool gear you have there.

The MCS meters are notorious for sticking. I've found other mentions of it in web searches. My take on it is that once the spring gets some tension on it (i.e. needle pegs), the pivot gets tight and the needle hangs.

I had a 3845 with one meter pegged so I pulled the meter and fiddled with the pivot point (I think it was a screw, but I can't remember). If you can get some lube in there, all the better. Anyway, once the pivot point was loosened up, the needle fell back to zero and worked fine after that.
 
Ah, good to know, how accessible are the needle pivot points? And yeah, they're pegged even with the power off, I took off the top and sprayed an entire can of electronics cleaner on the innards and alot on the meters but it seems theyre encased in a glass housing or maybe there's some way of getting under it? advice?
 
Electronics cleaner won't really help on the meters...it might not be good for the plastic lenses either.

If you pull the faceplate off the amp, you should be able to get to the pivots on the meters.

Be gentle with them, though. They're plastic and you're not likely to find replacements.
 
Most audio grade meters are in plastic housings. If I were you, I would experiment on a junk broken meter (maybe on one of the one's you have in your MCS) but only if you can locate a replacement meter.

I only say this because I have a box of over 200 meters that have come from equipment that I have pirated & torn apart from the last twenty years, from tuning, center, record meters, to watt, decible, amp & voltage meters.

You can carefully crack them apart with something like a tiny knife, razor blade or xacto knife blade, and carefully examine the inards. If you don't want to break it, then don't tear it apart, and look around for some replacements.

If you can post some pics, I can look in my box and see what I have.
 
Yeah, sorry for the delay, I've been crazy busy this week, Sunday I'll be back and I'll post some pics of it as best I can, so the housings can be taken off by the lower portion of the meters? Now that you say it, they are watt meters, so if that helps at all, but yeah, I'll post pics of it from as many angles as I can on Sunday, thanks!
 
Alright so I know this thread is ancient but I actually took it all apart today, got one watt meter working smoothly and when i went to do the other the screw was pretty much effed up in there and now besides filing down a new screw base into the adjusting screw, is there any way I can get just a "new" or NOS part to replace this?
 
I've fixed many of the MCS meters like you have. There were a couple that were beyond repair, and I used the watt meters from an Optonica SM-1515 donor unit I have. If I remember correctly, I may have had to swap out part of the plastic housing, but it was fairly easy, and the meters work great now.

Also, if the pivot screw is stripped, you could try gently "lifting" the needle away from the meter itself. Sometimes the heat from the back light melts and swells the plastic a bit - enough to push the metal range plate into the needle itself, causing it to stick. Of course, if you can see clearance between the needle and the metal plate, then the issue is with the pivot. There is another screw on the opposite side of the meter that can be be adjusted. One of the screws is covered from the factory with a plastic film that you'll have to break through to adjust the screw.

I hope this makes sense.
 
You must log in or register to reply here.
Back
Top Bottom