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This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Hello, long-time reader, first time poster. I've got a Beogram 4002 (hooked up to a Beomaster 2400 and out through Beovox 3000s), and I'm only the second owner after it was originally purchase in the 70s by my grandfather. It's been a trusty turntable and is still in relatively good condition aside from some wear to the lid.
In the last couple of months, however, anytime I've tried to play anything other than a standard 33 LP on it, the 45 selection button won't work, and the speed doesn't auto-adjust when I play a 7" record. The arm will still drop at the right point for a 7" or 10", but it simply won't change to 45 at all. I've taken a quick look inside, but a) there's no visible damage and b) I don't really know what I'm looking for, so am stuck at this juncture.
I'm based in London, so have tried to get it fixed by the closest recommended repair centre (J&A in Richmond), but they claim it's no longer possible to repair it. Saying that, when I took it in for repair for a separate matter (45rpm speed has always been inconsistent, slowing down at random for a revolution or two, which I've put down to lack of use on the part of the previous owner who had no 45 records, and the belt looks fine), they couldn't fix that either so I'm not entirely convinced by them.
At this stage my options are to try and repair myself (with limited knowledge) or keep it until it finally gives up the ghost (I can't get rid of it yet...there's too much sentimental value attached). I have another turntable that plays 45s with no problem, but would love to troubleshoot this one myself and get it working again. If anyone can pitch some ideas or what to look for, I'd be most grateful.
Thom
Try contacting Tim Jarman via beocentral - he knows his way around these decks better than most!
Peter
Take a look at this old thread. Lots of speed issues and advice and fixing them.
Thanks both Rich and Peter for your swift help - sadly it seems this issue isn't in that thread, though it made for some interesting reading!
I'll drop Tim a line as Peter suggests. Much appreciated for the guidance!
You can download the service manual here:
http://www.beoworld.org/manuals_view.asp?pid=294
On page 6, section 2.3, there's a full explanation about how the electronic speed switch works.
I'm just a hobbyist, but I fixed my 4004 by myself and I can tell you it's not an easy task... but with the help of the service manual, and other forum users, I got it working. If the (so-called) repair center tech told you that your 4002 is impossible to repair, my advice is to wipe off their number from your address book
It could be a faulty transistor - TR8 or TR12 - or the relay 1RL1 (mine had a broken winding): you could take off the plastic cover and try to clean the contacts, but you need to remove the PC board to do this.
Good luck.
B&O Beogram 4004, Revox B790/Audio Technica VM520EB, Yamaha CX1000/YSTA5/TX350, Philips CDP400/BDP3100,Technics RS-B965, Infinity Qbx, Audio Pro 4/40 MkII
Double post... sorry :-)
My first diagnosis would be to put the DMM probes on the 2 contacts of the speed-control relay.
Connect AC power, and press the 45 button, and see if the DMM registers a resistance of about 1 ohm. If that's what you see, the relay is fine.
If you see a resistance much higher than 1 ohm, there's the problem right there.
You'll need to replace the relay. But those relays are NLA, so you need a new standard Tyco or Schrack 24V 8A relay, wired correctly.
See that link posted above with all the speed issues for correct wiring instructions.
Menahem