"Dave Plowman (News)" wrote:

I'm searching for a replacement balance pot for an old Harman Kardon amp -
a PM645. It's an Alps 50k MN series - these are the type where the first
half of the travel doesn't effect the level but the second half does (in
other words no attenuation to either channel at the central indent), so a
special for balance use. Other Japanese amps of the period used them too.
The mechanical construction is standard dual gang 17mm body type with 6mm
shaft, and as it's PCB mounting a direct replacement would be nice.

The HK part number is 5113-50399122, but HK say they have no spares for
this amp. Alps don't appear to list this pot either. And I'm worn out
Googling. ;-)

If you can get the right type of log-antilog that'll do just as well nearly.
Failing that try 'slugging'a linear pot with a couple of resistors to bend the
law.

Graham