recently i bought a 40-year old beomaster 1400K. FM gives a fine stereo sound, a cassette-player connected to the tape-entry works also. But AM/LW/SW nothing at all. replaced a leaking capacitor , but no result. anyone with suggestions?
 the capacitor was 3000 uf 50Vdc, could not find a replacement exactly the same ,  now it is 2900 uf 40Vdc. also tried a 4100 uf 50Vdc but no effect. what's more important the uf or the voltage?

jogerr

Welcome to Beoworld !  

Both are important.
The uF to get the correct capacity and the voltage to achieve correct filtering and to insure nothing
explodes due to overload.
4100uF - that's not a standard value and never were. Probably misread 4700uF - is it a
new component or one taken from another set ?

Don't get me wrong, but mounting a 40V filter capacitor instead of a 50V leads me to think that
your Beomaster would be better off going to a trained tech guy. It's far too easy to destroy
rather than repair.
I'm sure it's not a costly repair.

If you feel confident about repairing this yourself, I will be happy to guide you,
these will be the first steps to take;
- Mount a suitable filter capacitor. 3300uF 50V should be fine. Alternatively 4700uF/50V.
- Do you have a suitable AM antenna or are you using the internal ?
- Contacts clean and dry ?
- Do the signal strength meter do anything as the dial is travelled ?
- Do you have static or hiss or nothing at all ?
- Power supply voltages correct and ripple-free ?
- Power reaching IF and AM frontend circuits ?
- Is the AGC line reacting ?
- Local oscillator running ?
- DC voltages on IF transistors correct ?

Martin

Martin,

thanks for your help with all the instructions, that made me think and test.

I found out that touching the mainboard at centain spots helped, so  there had to be  a bad  contact or connection.

It took some time till I found it: the long pin used as a spring to take care of the release or return of the buttons on the front panel, had moved so far to the left that it was now touching  a pin on the mainboard.  pushing it back was the solution.

now i can receive transmissions on AM/SW/LW.

although the radio is now operating on 40V capacitor,  i will try to get me a 50V one to be sure.

and, it was not a mistake, the other capacitor was as a matter of fact  4100 uF 50V (but too large to put in the beomaster)

jogerr.

Great job, one to note ! 

Martin