Beomaster 6000 (2702) restoration: ultrasonic receiver and tone amplifier

Another PCB where everything is very tight and space is limited: "PCB 14, remote control receiver". Luckily not that many capacitors but also a few trimmers that I wanted to replace. And there I found again something interesting: the trimmers only had 2 legs ! The slider contact that typically sits in the middle, was here one of the two outer contacts. Never seen this before. So I had to modify the multi turn trimmers that I wanted to use. Not a big issue however.

The added advantage of using this type of multi turn trimmer on this PCB is that it is now reachable from the top and does allow setting without removing the PCB. This was not the case with the original trimmers.

Recapping the tone amplifier was pretty straight forward. All easy reachable capacitors. As you can see, this board is still attached tot the potentiometers (the string of coloured wires).  I did not want to unsolder all those wires unnecessarily . 

Beomaster 8000: Recapping the Filter and Tone Control Board

The last Beomaster 8000 PCB that needed its electrolytic capacitors replaced was the Filter and Tone control board that sits underneath the control panel of the unit. After unsoldering the signal strength meter leads, I removed the board from the control panel. Here are is a photo of the board in its original condition:

And after replacing the capacitors with new 105C types:

And a detail shot (the two AD13 ICs are the 64dB volume attenuators for the right and left channels):

Time to put the Beomaster back together and test the 3D printed control panel latch!

Beomaster 8000: Recapping the Filter and Tone Controls Board (#4) and Broken Signal Meter

I moved on to recap the filter and tone controls board (PCB #4) that is under the control panel of the Beomaster 8000 I am working on...not much to report about the capacitor replacement. Here are pics:

Before:

and after:

Sadly, the more 'interesting' part of this board is the non-working signal strength meter. I unsoldered the contacts and measured the resistance. It is open circuit, i.e something is wrong on the inside. It looks pristine inside, from what I can tell by peeking through the plexiglass cover. I am wondering if one can open it up without penalty...I guess, we will find out soon.