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
I blew up my Beomaster 3000-2 left channel when I was adjusting the Bias.There is now no voltage over the big resistor nor there is current between de adjustment points.Of course there is also no sound coming out of the headphones or speakers.You hear a very soft sound maybe distorted so the channel is blown.Any suggestions what parts I need to change ?
Would love to get this receiver running again as it is a great looking and super soundingreceiver.
I took out the 2N3055, these I think are ok.
UPDATE :Found the error.To adjust the Bias you need to remove the connector.This went rather difficult (more 40 years old).The force provided was the cause that the PCB broke where the pin is soldered.Hardly visible but the little wiggle of the connector made me suspicious. So turned out to be an easy fix.
Welcome to Beoworld !
Which connector?
Martin
Thank you for the welcome.
If you look at at the PCB you find 2 pins on which there is a connector.
Here you can insert an ampere meter and adjust the bias.
Thet are in the middle of the amplifier PCB.
I have 2 beomasters, the 3000-2 and the 4000.
The 3000 is almost mint.The 4000 shows its age and the swtich block is malfunctioning.
I do have many vintage amps and receivers but the beomasters are really good.They sound great and also look great.
Oh those. I never use them.You can set the idle current by simply measuring the voltage across one ofthe emitter resistors. This way you don't have to break the circuit.
Hi Martin.I adjusted the Beomaster 4000 I have according to the methode written in the Service Manual with the ampere meter.I read somewhere on a forum that the voltage over the resistor for the Beomaster 3000-2 should be 10mv.Is that correct ?
10mV sounds about right.