ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Dear Forum,
I have recently bought a Beomaster 901. It works fine playing music from both my record player and aux-connection.
However - the heatsink on the back of the amplifier gets very (worringly) warm. According to a forum thread somewhere I read it is due to too much idle current being drawn. It is the right hand side of the heat sink when viewed from the front/top gets the warmest.
STATS @ ZERO VOLUME: After Running 5 min - 0,19 AMP @ 235 V [Voltage selector set to 220 V]After Running 10 min - 0,21 AMP @ 235 V [Voltage selector set to 220 V]
After Running 5 min - 0,19 AMP @ 235 V [Voltage selector set to 240 V]After Running 10 min - 0,17 AMP @ 235 V [Voltage selector set to 240 V]
Anybody got any suggestions on how to solve this? I am not confident enough in electronics to fix the circuit board myself, but would like to know what the issue is. (I live in Copenhagen, so I believe there are qualified Bang & Olufsen-repair-people around).
/Staffan
Hi Staffan.
I just picked up a 901 with this exact same issue. I'm tempted to just replace all the output transistors just for the heck of it... but did you eventually find a solution?
Hello Staffan
on mine 901 recently restored I changed both trimmer 1K and fixing on 10-11 mV across 0.39 ohm resistor without warming on heatsink.
Same changes shoulf be done on 500 ohm trimmer to set right 32 V on supply voltage.
Have a nice Tuesday
MArco