I've got a beautiful Beomaster 1900 that has distortion with volume increase and intermittent right channel failure. What I've done:replaced the electrolytic and the filter caps. Replaced the idle trimmers and adjusted per service manual. Replaced the R151 trimmer for the 15V supply. I was only getting 13V at TP15 and no changes when adjusting the R151.All lamps are working. 13V at TP 16 with a good wave form on the scope (I'm still learning to use this though)13V between the rectifier and R147.Green rectifier test good. D50 rectifier test good. 2A quick fuse replacedstill 13V.C95,96 100nF caps replaced, (one was a tropical fish, one wasn't)13.5V now and still no changes with trimmer R151.
What am I missing?
What is your AC current
Collecting Vintage B&O is not a hobby, its a lifestyle.
If D50 is still the original part, I suggest you replace it.They often measure fine but they are known to break down under load.
Dillen:If D50 is still the original part, I suggest you replace it. They often measure fine but they are known to break down under load.Martin
Sure you can. Go ahead!
AC current from transformer to D50 (9) (10) in the drawing ??, 95V when on doesnt sound right, please measure again
I ran my BM 2400 with a 4A 80V rectifier, no problems, now go after your left channel, cross checking with the right channel, with your scope
Well done then!