Sign in   |  Join   |  Help
Untitled Page

ARCHIVED FORUM -- March 2012 to February 2022
READ ONLY FORUM

This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022

 

Beomaster 1200

rated by 0 users
This post has 5 Replies | 1 Follower

Aad Jansse
Top 500 Contributor
Rotterdam (Neth)
Posts 236
OFFLINE
Bronze Member
Aad Jansse Posted: Sun, Sep 20 2015 1:04 PM

Listening to the output of various Beomasters was not enough for me so I did not hesitate to accept an offer from someone to take over a silent BM1200; "see what you can do with it". There appears to be a bad contact in the powerswitch or something, anyway after fixing this I got radio receipt, but no Tape or Phono comes through. Where could I start looking for a solution of this problem.

Second question, where is TR145 ( a 60054 or 2N5034) located inside  this 1200?

 

Aad Jansse
Top 500 Contributor
Rotterdam (Neth)
Posts 236
OFFLINE
Bronze Member

By listening better I can hear a faint sound when engageing Tape or Phono, only when the volume sliders are set in maximum position.

Dillen
Top 10 Contributor
Copenhagen / Denmark
Posts 13,191
OFFLINE
Founder
Moderator
Dillen replied on Sun, Sep 20 2015 2:54 PM

A too high ripple will often cause silence in this model, so there's a place for you to start.
The voltage regulator sits together with the output stage transistors at the bottom plate, using it for cooling.

Martin

Aad Jansse
Top 500 Contributor
Rotterdam (Neth)
Posts 236
OFFLINE
Bronze Member

Hi Martin, Thank you for your quick Sunday reply.

Pardon me my asking , but do you mean a ripple on the voltage from the powersupply? to check this shall I start with the big (3000/64) cap?

 

Dillen
Top 10 Contributor
Copenhagen / Denmark
Posts 13,191
OFFLINE
Founder
Moderator
Dillen replied on Tue, Sep 22 2015 6:19 PM

The power supply, yes.
Check it with a scope.

Martin

Aad Jansse
Top 500 Contributor
Rotterdam (Neth)
Posts 236
OFFLINE
Bronze Member
Aad Jansse replied on Tue, Oct 13 2015 11:47 AM

 

With the help of a "Beofriend" we found out, thanks to the professional suggestion (quote user="Dillen":"Check it with a scope"), that the 'Phono' problem was caused by the absence of a pre-amp. I connected a BG1500 to the BM1200: on the scope we saw a faint signal . Now I have music through a NAD PP2 pre-amp that I happened to have.

The 'Tape' was connected with a cord (why did I pick just this one?, I have numerous ones) with a faulty DIN plug!!

So all's well that ends well.

Thank you

Page 1 of 1 (6 items) | RSS