Need help finding a Pot for my head.

[creis2]

So I scooped up an Ashdown Klystron 500 head for cheap off of eBay. Of course, Fedex destroyed the box it was in. The input pot (gain) snapped off with the knob, I can't move it.

Obviously the pot needs to be replaced. The seller offered to take back the amp and have it repaired, but I don't want to risk any more damage with shipping and I can easily do the repair myself.

I tried to contact Ashdown several times, with no response. Does anyone know where I can grab a schematic for this head, or does anyone know what type of Pot I need?

How to I test the pot with an ohm meter?

 

[grendle]

Their usually labeled for the value, a generic pot will work, check digikey or mouser. The pn on the pots is usually a special for the mfr only. Just gotta check the dimensions. Or you can order that pn# through a local dealer / repair center.

 

[fdeck]

If the pot isn't destroyed on the inside, you can measure it with an ohmmeter.

Don't give up on the part number. The maker might have used a generic pot in order to save money. What are all of the markings on the pot?

 

[will33]

I know this guy down the street....he's a head...could prolly get a lid or somethin'....

 

[chuck norriss]

Come to California. Plenty of pot for your head.

 

[Count Bassie]

It took 4 posts to start the party rollin' here! What's the matter, people??

 

[T-Bird]

Hi.

IME most of the manufacturers unfortunately use hard to find (nowadays anyway ) potentiometers.

What makes matters worse, is that the potentiometers are usually mounted onto the PCB, so unless there's plenty of room there, just any (better ) potentiometer just won't fit. If You can find one with the same electrical and physical values as the old one, it's easy to wire it to the PCB though, something I have had to do sometimes.

One option that I have used a few times with vintage equipment is to drill and tap both the separated shaft portions and attached 'em with a screw. Requires some skill, but is perfectly doable and can literally save the day.

If You're confident enough and understand the safety precautions when working with el. appliances, pop the lid open and take a pic of the potentiometer in question. Someone will surely come up with a substitute, if not the exact one.

Regards
Sam

 

[madmachinist]

have you removed it from the circuit yet ? you won't get
a good reading unless you at least remove the outer
connections , then measure resistance of the outer two
contacts - that should give the value of the pot.

it won't tell you if it's a linear taper or an audio(logarithmic)
taper - the amp will function with either kind , but if you get
the wrong one the volume might act a bit quirky .

the good news is that pots are relatively cheap - i'd order
one of each -that way you can try it out and swap them
if you don't like the action of the first --before you put the
amp back together.

make sure the replacement has the same mounting length ,bushing style ,shaft diameter + length, and type (round, split ,knurled , flatted , etc) to fit your knobs.

good luck.

 

[JimiLL]

Come to California. Plenty of pot for your head.

So beat me to it

 

[Budbear]

So many jokes, so little time.

 

[JimiLL]

So little weed as well