HK Citation 1

[PF Sound]

OK......was it tough to find the wafers?
This thing is kind of a PITA to trouble shoot. I found an issue with one of the resistance readings going to pin 2/V4......it should read around 200K (to ground) via the cheat sheet but it's over 900K.....chasing down an elusive 680KR as per schematic.....not finding any in the unit, lol

 

[jefferylhenr]

OK......was it tough to find the wafers?
This thing is kind of a PITA to trouble shoot. I found an issue with one of the resistance readings going to pin 2/V4......it should read around 200K (to ground) via the cheat sheet but it's over 900K.....chasing down an elusive 680KR as per schematic.....not finding any in the unit, lol

No, it wasn’t easy. I would probably just rework an alps pot and replace it altogether

 

[PF Sound]

I appreciate your replies to this old thread.
I disassembled/cleaned the volume pot & it's only part of the issue. One side measures 499k & the other 580k. The way the switches/pots are bridged makes it challenging to know what is a good reading & what isn't. The other problem was a broken wire at the base of turret.........getting there.

 

[jefferylhenr]

With mine, one of the carbon wafers literally fell apart. Do some research on ALPS, they make some high end dual pots that should make a much better replacement vs the original or trying to repair it. You can also search for units of that era that have the same resistance as these to give you a wider range of parts to search. I have been using chat gpt for this. Still need to find a citation II, but everything that isn’t all beat to death is $3-4k and I can get a Luxman, McIntosh or Sansui for that money.

This might be something to try? https://guitarelectronics.com/alpha-500k-audio-taper-dual-ganged-stereo-control-pot-for-guitar-bass/

 

[PF Sound]

Thanks for the tip on new pots. I'm going to check the balance pot & then decide if replacements will be the best ave. This is a friends unit. Apparently it was his older brothers unit that was shelved 30-35 years ago. It ain't mint but it isn't hammered......has all original face/knobs/switches, just not in pristine shape.......only one tube bad. It had all but a few of the original bumble bee caps replaced at some point so I finished that. I've worked on a few tube guitar amps but am pretty much a SS guy, so this thing is a bit of a different animal for me.

 

[jefferylhenr]

I finally found the citation II and I now want to upgrade the citation I volume pot to an alps. Don’t know why this is so much a mystery? Have done quite a bit more work on both.

 

[Mr Boochie]

Sweeet!

 

[TriodeLuvr]

I finally found the citation II and I now want to upgrade the citation I volume pot to an alps.

Alps doesn't make a direct replacement. The Citation 1 volume pot has two taps. Do you have a solution for that?

Jack

 

[gadget73]

Hm, one for loudness i assume, what's the other do? Kinda looks like it would mostly just modify the taper.

 

[TriodeLuvr]

It modifies the taper and the loudness set point.