Siemens 295b help...sst117/1 transistors?

[Tungstengruvsten]

Hey all;

been super busy lately with work, just taking some time back for myself to fire up the soldering iron and drill press!

Anyways, I've got a pair of 295b's that need fixing - had a couple resistors way out of tolerance in the output stage and I need to replace the output transistors...these are sst117/1's....anyone have a few around? I found one place but they had a minimum order of 100....I need 10 tops. Is there a replacement for them?

Here's a link to the 295b schematics description etc:

http://www.kubarth.de/cgi-bin/diy/german/index#w

Also in the output stage, there are 2x 5k trimpots on the output with a 22uf cap between the wipers...R29 and R30 on the schem... what are these used for? Symmetry? How to adjust them properly?

Any help is welcome!

 

[Rossi]

SST117 is the same as BSX45, or at least very similar.

 

[martthie_08]

speaking of "295b's that need fixing" - can anyone tell me if I can still find some rotary switches for the puppies? They were made by elma, quite compact and have a strange shaft size, not 1/4 inch...

 

[andre tchmil]

Tungstengruvsten !
I think I have some original ones.
Do you want me to look for them ?

 

[martthie_08]

Also in the output stage, there are 2x 5k trimpots on the output with a 22uf cap between the wipers...R29 and R30 on the schem... what are these used for? Symmetry? How to adjust them properly?

R29 is amplification / R31 and R18 are for symmetry.

R77 through R84 are trimpots as well. There are lots of points of adjustments in this schematic. Although I know nothing about the adjustment procedure, I can say that properly tuned units do sound noticably better than old / out of spec units. I have several w295(a/b) in various conditions - from mint to not-working

cheers, Marten

 

[fluxivity]

Tungstengruvsten !
I think I have some original ones.
Do you want me to look for them ?

Hi Andre. Voices from the past on this. I’ve got a few of these that need the prasenz switches to be functions again. Any chance you Still have some? Or does anybody know a part that might work? Thanks

 

[Lampie519]

Same issue with mine. I think you can get these from Grayhill or C&K.
https://www.grayhill.com/documents/56-Datasheet10 positions 36'