25k ,50k locking potentiometers for bias

[Tone Junkie]

Sorry to put this here but in the past someone had posted a good link to some good quality pots i cant find it. Its in my last computer that crashed a while back, damn machine
Thanks Bill  b b 

[Willabe]

Webber speakers has them. 25K/50K locking pots. Small size, low cost. Bought some, have'nt used one yet , but they look/feel pretty good.


          Brad     

[Boots Deville]

I've used the Weber locking pots with success, but if you'd like some other options, here's a digikey part number for a PEC 25K locking pot:

RV4L253C-ND

Probably better quality than the weber offering.

[stingray_65]

I too have used those small Weber pots with success. But I always felt they were cheap somehow, not that they ever failed me yet.

In the past I had modified full sized CTS and Alpha pots by marking the shaft with a scribe and disassembling them so I could cut the shaft just below the scribe mark. I would dremmel a slot in the shafts end and reassemble them.

I then felt that somehow my monkeying might compromise the pots, until I read a recent post by Doug stating the same technique.

Those tiny locking pots need a tiny screwdriver and are easy to slip out of. The modified CTS pots have a lip created by the pot barrel and a larger screwdriver is prevented from slipping around.

Besides that, between Alpha and CTS  you have a pretty big variety of values to choose from too.

Just offering another avenue to pursue.

OH!

After the Bias is set, a dab of nail polish on the shaft adds a bit of hold to prevent accidental adjustment and gives a nice tell tale  if someone does try adjusting the bias.


Ray

[Tone Junkie]

Thanks guys i like the Weber 2watt conductive plastic . But I hate how long it takes to get things from them.
Ray thanks for the nail polish trick never thought of that
Bill

[DummyLoad]

PEC - digikey..

25K part.

http://search.digikey.com/scripts/DkSearch/dksus.dll?vendor=0&keywords=RV4LAYSA253A

50K part.

http://search.digikey.com/scripts/DkSearch/dksus.dll?vendor=0&keywords=RV4LAYSA503A

--DL

[Ed_Chambley]

I have some of the ones DummyLoad linked to.  I have them in 4 of my amps and they are great and look and feel practically indestructible.  That was until Doug told me about cutting them.  I will never pay $9 plus shipping again since Doug told me this.  I couldn't believe I never thought of it.  I used a ziz wheel or wizz wheel, whatever you want to call it.  Cut the shaft about 1/16 below the edge of the hole on the pot.  I cut 4 slots down through the threads. Mounted it and then squeezed another nut just a little making the opening squeeze on the shaft to get resistance so it will not turn unless I loosen it a bit.  Opened up a whole new world of options for pot values for bias.  The coolest thing is I did not have to wait for anything or weed through mouser or digikey's website.  I would have to say it is one of the best suggestions I have been given in a while.

[stratele52]

I always use mutiturn cernet potenetiometer. Their 10 turn won't change by itself and they are low cost

http://www.futurlec.com/PotRect.shtml

[Tone Junkie]

I like the reguler style potentiometers with the locking nut because then I can put them through the bottom side not to far from the tubes so I can change the bias without pulling it totally from the head or amp Im lazy.