BeoGram

Re: Beogram 4002 Drive Motor

yachadm — Sat, 24 Jan 2009 15:02:47 GMT

You're right!

I was concentrating on the motor issue with the cap, and got sidetracked into thinking of the 2N3055.

The 2 TIP's are hard-mounted on the chassis base - I remember I had to replace them, but used more robust substitutes - BD241 for the TIP31 (NPN), and BD242 for the TIP32 (PNP).

Menahem

Re: Beogram 4002 Drive Motor

tournedos — Sat, 24 Jan 2009 14:34:17 GMT

yachadm:

That 2N3055 is a warm transistor at the best of times, and is widely counterfeited.

Hello Menahem Isn't that the one in the power supply, mounted legs up nearby the motor? I was referring to the two transistors that form the amplifier for the motor drive. I have to admit I never even noted where these were located physically when I had my BG6000 open...

Re: Beogram 4002 Drive Motor

yachadm — Sat, 24 Jan 2009 14:08:07 GMT

That 2N3055 is a warm transistor at the best of times, and is widely counterfeited.

I got a suggestion from a member at my Tektronix O'scope forum that a 2SC5197 or 2SC5198 is a much better bet.

And if that 150uF BiPolar cap is impossible to find, a much more common 220uF BiPolar will do the job just as nicely.

Menahem

Re: Beogram 4002 Drive Motor

tournedos — Sat, 24 Jan 2009 13:09:54 GMT

Ouch. Well you'll need to replace at least that transistor, then. Fortunately they are easy to find and cheap.

Re: Beogram 4002 Drive Motor

MrGrey — Sat, 24 Jan 2009 12:34:44 GMT

I just out my multimeter on TIP31 and broke it. It's now getting rather warm and the motor has stopped doing anything at all.

Re: Beogram 4002 Drive Motor

tournedos — Fri, 23 Jan 2009 10:56:17 GMT

Those were nice presents! Is she available? ;-)

Sounds like you have the AC motor version. From what I understand, this could be a failure of the phasing capacitor (150uF bipolar, one of the four) or the motor itself. You should also check the voltage at the other end of the 4000 uF cap feeding the motor (another one in the bank of four) - it should show 11,4V in average. If not, one of the transistors driving the motor may have failed - I think TIP31 and 32, in TO220 case mounted somewhere off the circuit boards.

I presume one of the experts will correct me sooner or later, I just jumped in because we have a lot of traffic now when the forum is back online. Welcome, and I'm sure we'll have your Beogram sorted sooner or later!

Beogram 4002 Drive Motor

MrGrey — Fri, 23 Jan 2009 09:36:41 GMT

I received a Beogram 4002 from a co-worker yesterday (after she gave me her vinyl collection!). Everything appears to be in working order except the platter will not spin. I took the platter and top panels off and noticed the motor that drives the belt is not spinning. If I rest my finger on belt wheel I can feel it moving back and forth (almost like a vibration). The movement speed does increase if I change from 33 to 45. I'm not sure if this is the AC or DC motor, but it does have four large capacitors directly above it.

Just wondering if it is a motor or capacitor issue (or something else)?

Any insight is greatly appreciated.