The service manual is on site. However check the record player first - more likely the stylus is shot than anything. If it plays well though another amplifier, the BM2200 service manual is on site but you will need to be a silver member to access it and be competent with circuit diagrams and have the right equipment!

I agree with Peter, the cartridge could be the sole reason.

Having said that, the phono input is the most sensitive in the Beomaster, so is
usually the first to be affected by f.e. an unstable power supply.
I would grab a capacitor kit and replace the lot. Aging caps are the cause
for the majority of faults in these wonderful machines.
I'm sure that, if the caps in your Beomaster hasn't been renewed yet, the ones
on the power supply module (at the bottom center of the Beomaster) will be
visibly cracked. Probably others as well. Those red cylindrical ones are horrible.
Replacing caps is a job for a person with electronic knowledge and soldering skills.

If you take the Beomaster apart, note the little spring for the aluminum lid. It sits on
the horizontal black rear metal plate under the black top aluminum cover.
Of course, it would be worth upgrading your membership and get the whole servicemanual.

Martin

Thanks Martin, I have the original documentation for the BM2200 which includes good circuit diagrams - will the service manual offer much additional information?. In a previous life I was a computer engineer so I'm comfortable with electronics (less so with analogue!) and soldering etc.

I notice the 35V supply to the phono circuit is down to 32.4V but I haven't yet had time to trace much further. You mention a capacitor kit - do you know of a stockist who has a kit for this machine?

Thanks to you and Peter for your help.

Gordon 

Gordon,

The voltage is not the huge problem, it's essential that it's clean and free from ripple and noise.

You have a message regarding capacitor kit, check your inbox in the top right corner.

Martin

Thanks Martin. I have now replaced all of the electrolytic caps and noticed C3 in the power supply had been leaking so I thought I had found the culprit but unfortunately the problem remains.

I have also just repaired my Tektronix 465 oscilloscope wich I haven't used for about 5 years (also a cap problem!) so now I can monitor the BM2200 properly.

I see about 50mV of quite noisy ripple on the +35V supply line and the waveform looks sawtooth. Is that what you'd expect? 

Good job on the caps. Now we know that that part is alright.

The amount of ripple is no problem. The sawtooth waveform is to be expected and not a problem either.
You will have to connect a signal generator to the phono input (or play a test-record on a turntable) and use the scope
to find where the signal gets distorted.

Martin

Thanks Martin. Whilst I'm waiting trying to find a test record, I measured around the power supply and here's what I found, I'd be grateful for your comments:

P31-1, -31.53V, 250mVpp sawtooth ripple

P31-2, +31.15V, 580mVpp sawtooth ripple (note I swapped over 5000UF caps and this stayed on the +30 supply)

P31-3, +33.0V, 50mVpp noisy ripple

P31-4, +14.8V, 20mVpp noisy ripple

P31-5, 6.21V, 1Vpp 50Hz sine wave

P31-6, 21.8mV

P31-7, -26.3mV

P31-8, GND

P31-9, GND

With the new caps installed, if the problem is limited to the phono input, I think we
can rule out the power supply.

Did you try using a different needle/cartridge or turntable ?

You could also check inside the DIN plug on the turntable signal cable. Especially the ground connections.

Martin

Thanks Martin

Unfortunately I don't have access to another turntable or cartridge so I'm just going to have to try to debug this the hard way. I have been in touch with the previous owner of the 3000 who is very trustworthy and says the turntable and cartridge are both good. Unfortunately, he now lives about 500 miles away so I can't use his components to isolate/test.

I'm trying to find a test record so I can check the path from the stylus all the way through the phono amp.