Telefunken

[JimmyEJames]

Hello tube people
I have very nice big receiver from Germans it has nice amplifier like this type
http://www.tube-classics.de/TC/GermanTubeHifi/Poweramps/Telefunken 2430/2430.htm
I want to make so I can use every day and it is all original so I know it needing caps and clean at very least plus get rid of selenium rectifier and make sure line AC adjusted correctly!
I have never work on German amps like this so I would like to ask for ideas and what to look out for to do nice job and preserve quality
It is first very delicate job just to remove from cabinet!
It is in working state so maybe I just do amplifier and leave rest alone just clean? I have not made decision. But I would still like idea on parts and tips from anyone who knows these
I have Telefunken speakers that match too
My receiver is this I am almost scared to open it is looking like new
http://www.radiomuseum.org/r/telefunken_opus_5430mx5420_m_hi_fi.html
Thank you
JJ

 

[primosounds]

Since the layout of the components is 3 dimensional you will need to be very careful. Sometimes in such a layout you will need to remove stuff just to get to where you need to go. On such an old piece removing wires and components will inevitably lead to broken parts which need to be replaced. So such a layout is not user friendly. My advice is to use it until you are ready to do a full rebuild. This does not involve the power supply which obviously needs to be working properly. But if testing shows that the power supply is at the correct voltage level and there is no DC on the grids of the power tubes, and no bad smells or hot can caps, then probably use it for a bit.

 

[Pio1980]

I have a similar Grundig NF-10 that needed very little to come back to life. All small elyticaps, especially Frako, should be replaced. The selenium rectifier may be tired and need replacement, also the big elyticaps.
If the amp was checked powered up as is and the big elyticaps and selenium didn't get warm or humming come from speakers, fuses didn't blow, the power supply may be OK.
The small plastic film caps are usually ok. Do have tubes checked if channels don't sound equal.

 

[toshik]

My Telefunken Opus 5550 MX (2550 EU version) has a similar amp/ps board and looks pretty much the same. Just take your time some caps on the turer board are major pita to repace, but can be done. Large 400 uf on stereo indicator pcb was completely dry in mine.