Beogram 4500 servo motor

in Imported Content (Unmapped) · Feb 8, 2022 17:38 GMT

The pin 9 on IC1 stays solid at 5 volts whether i operate the < or > button. As for resistance from pin 21 and 22 to GND with the unit unplugged i measure 46.6KΩ and 44.5KΩ respectively. Both numbers are not solid, and k…

Beogram 4500 servo motor

in Imported Content (Unmapped) · Feb 6, 2022 21:46 GMT

[quote user="manfy"]I'm not quite sure how to interpret your voltage measurement...is that across the motor terminals?[/quote] Yes it was across the terminals by operating the < and > buttons. I did the above mentioned t…

Beogram 4500 servo motor

in Imported Content (Unmapped) · Feb 5, 2022 11:16 GMT

OK the parts arrived and finally i found some time to replace them. I replaced the Zener first and had the same readings from the OpAmp. I then moved to replace the OpAmp itself. (thanks manfy for the alternative) I now …

Beogram 4500 servo motor

in Imported Content (Unmapped) · Jan 22, 2022 19:26 GMT

Thanks Mark and Manfy for the troubleshooting, I'll replace the Zener and will share the results.

Beogram 4500 servo motor

in Imported Content (Unmapped) · Jan 22, 2022 15:17 GMT

OK further to your suggestions the CPU outputs 21 and 22 give 5.15V to GND, the same goes to opamp 7 & 8. Opamp outputs 1 and and 3 give 3.51 and 3.62 to GND respectively. Pin2 of IC2 to ground outputs 3.64V The 5V and 1…

Beogram 4500 servo motor

in Imported Content (Unmapped) · Jan 21, 2022 09:33 GMT

Thanks Mark, Yes the motor is spinning and changes direction with reversed polarity (i gave it 5.6V and is works nice). The unloaded measurement switches polarity with << or >> and gives the same 3.6V either way. I will …

Beogram 4500 servo motor

in Imported Content (Unmapped) · Jan 19, 2022 21:34 GMT

OK you are right the motor was puling down the voltage. With the motor disconnected i measure 3.6V from the board and not 7... Do you think it could be a bad capacitor?

Beogram 4500 servo motor

in Imported Content (Unmapped) · Jan 18, 2022 19:25 GMT

Thanks for the reply Mark, With ''string'' i mean the... 'wire' that connects the pulley with the sliding chassis. But the rubber belt you are referring to is also OK. Good hint on that pulley being loose but not in my c…

Beogram 4500 servo motor

in Imported Content (Unmapped) · Jan 14, 2022 21:01 GMT

Hi all, I have an issue with my beogram 4500. The servo motor does not work. When i operate the arrows, the deck responds and does what it should (starts spinning, raising tonearm turning the light on) but will not move …