Old Allen Bradley Pots

[dreric]

I've been looking at these on ebay and it seems that most are listed as "type J" but some are described as linear and some audio tapers.

http://www.ebay.com/itm/110789697397?ss ... 1423.l2649

Does o anyone know the specs? specifically how to distinguish between linear and audio tapers?

Thanks

Eric

[selloutrr]

Some batches have a "B" to indicate Linear taper. Others are assumed to be Linear taper unless marked "A" for audio. Some are also Marked "L" for linear. Not all Allen Bradley pots were producted by Allen bradley each factory had it's own stamping practice.

The link to the auction states Linear taper.
The back of the pot is stamped S-"L"-?-Meg
"L" stands for Linear.

If you do a search on ebay for "Allen Bradley Type J Linear" and "Allen Bradley Type J Audio" and look at the back of the pots you can see what I mean.

[Structo]

I don't know if it was a coincidence or what but I bought two 1Meg NOS Allen Bradley pots and they turned out to be bad.

One jumped way up in resistance after about 1/4 turn.
The other was way out of tolerance.

I was bummed because they were in my new 100w build for the volume and master.

[diagrammatiks]

the mil spec codes are this...

A = linear 10%
B = linear 20%
C = logarithmic
10%
D = logarithmic
20%
E = reverse
logarithmic 10%
F = reverse
logarithmic 20%

the internal codes are S = linear
z= log.

type j is carbon conductive element.

can't wait for that lead dress guide dreric.

merry christmas.

[dreric]

Thanks guys!!!!

[dreric]

can't wait for that lead dress guide dreric.

You know far more than I, my friend.

Merry Christmas

Eric