If this is just an audio amp, you can replace the entire board with a modern class D amp for less than the price of a replacement transistor.

Edited to add: And get better sound out.

Hi Bob
I would like to keep the vintage machine as original as possible, so that would be a last resort.
Dave

 

Here are some PNP Ge power transistors in TO-3 package.

https://www.jameco.com/Jameco/Products/ProdDS/2286039.pdf

https://www.jameco.com/z/2N2833-Maj...-Transistor-BJT-PNP-75V-20A-TO-3_2286039.html

Look at those Icbo values!


Those transistors would self bias themselves.

 

If this is just an audio amp, you can replace the entire board with a modern class D amp for less than the price of a replacement transistor.

Edited to add: And get better sound out.

Hi Bob
I would like to keep the vintage machine as original as possible, so that would be a last resort.

 

Hi Bob
I would like to keep the vintage machine as original as possible, so that would be a last resort.

I understand. Much like people who restore antique furniture. It loses value if you replace any major part of it.

 

You might want to contact Bill Bickers from Jukebox Friday Night in Georgia. I have been sending juke amps and receivers to him for years. He typically has NOS components and he has enough knowledge on specific units to recommend part swapping to modern equivalents.

 

You might want to contact Bill Bickers from Jukebox Friday Night in Georgia. I have been sending juke amps and receivers to him for years. He typically has NOS components and he has enough knowledge on specific units to recommend part swapping to modern equivalents.

Hi Thanks for the heads up. Looks likes he knows his stuff. With all the help I've been given by Mr Chips and others I'm going to upgrade to the Silicon transistors and see how that works out.

Regards,

Dave

 

If you're going the silicon route, R24 and R26 will probably need to be about 6,8Ω for a similar bias current to the original.

 

If you're going the silicon route, R24 and R26 will probably need to be about 6,8Ω for a similar bias current to the original.

Hi Alex
Thanks for the info. Much appreciated. When I have all the new caps and bits I'll let you all know the results.
Dave