Anyone heard of wirewound volume controls?

[Arkless Electronics]

I've known them used in line with speakers as a rather direct way of controlling the volume....:eek:
But what I have found is an old dual gang precision 10K wirewound pot on a panel from an old and long scrapped piece of test gear :eyebrows: Yer see where I'm going here ;) It's linear of course but some log faking resistors should sort that out. I'll do a few measurements and see if its inductance is too high etc. Could make an interesting new take on the volume control front. Or maybe not. Anyway a few bigger fish need to be fried first but I'll report back in a few days probably.

[walpurgis]

Like this maybe?

http://www.ebay.co.uk/itm/L-Pad-Attenuator-15W-8-Ohm-Wirewound-Volume-Control-/231018741130?hash=item35c9ca3d8a:g:TTAAAMXQCZ1Tcil ~

Often used to control tweeter levels. They are intended to approximately match the impedance of the tweeter and offer the same load across their operating range. This prevents the crossover points from being affected (hopefully). Not a good idea to use them with bass drivers.



I've got a box somewhere with some ancient examples of wirewound pots of varying values and some are linear and some are log.

[Barry]

I've known them used in line with speakers as a rather direct way of controlling the volume....:eek:
But what I have found is an old dual gang precision 10K wirewound pot on a panel from an old and long scrapped piece of test gear :eyebrows: Yer see where I'm going here ;) It's linear of course but some log faking resistors should sort that out. I'll do a few measurements and see if its inductance is too high etc. Could make an interesting new take on the volume control front. Or maybe not. Anyway a few bigger fish need to be fried first but I'll report back in a few days probably.

They are used in high current situations, when a carbon track device would be inadequate.

[Arkless Electronics]

Yes guys I'm well aware of their use at high power levels :) This is a unit designed for precision rather rather than power handling

http://www.bartola.co.uk/valves/wp-content/uploads/2014/03/IMG_0554.jpg

Colvern like the one on the bottom right but mine is 10K +/- 2% dual gang. Yes they're that old!

[walpurgis]

Yeah. Pretty sure I've got a few somewhere in the workshop. Might even be some dual gang there.

[Barry]

I've got a few of those Colvern pots as well, though I don't think they're wire wound.

[Arkless Electronics]

I've got a few of those Colvern pots as well, though I don't think they're wire wound.

I don't know if yours are different but mine, like the one in the photo, says "wirewound" quite prominently on the back in a handwriting type script...

[walpurgis]

If they're not marked, you can tell if they're wirewound by listening to them as you turn the shaft. Carbon track pots don't make much noise, wirewound ones 'buzz' as the wiper follows the track windings.

[Barry]

I don't know if yours are different but mine, like the one in the photo, says "wirewound" quite prominently on the back in a handwriting type script...

I would have to find them to see if they are marked "wirewound". They are single pots and almost certainly linear law. I think I have some more modern looking Colvern pots that have a rating of 3W. They are about 1" in diameter and have a low resistance.

[Arkless Electronics]

It seems age doesn't treat these things kindly .... it is, to use an engineering phrase, fucked :steam:

[struth]

Used to get quite a lot of those when I was a lad. Can be used for audio situations and were, including tvs I remember. they get dodgy though as the wiper is inclined to get loose and the wire thats wound round the former can become loose and look like a spring:D not seen on for years although sure they are still made.. think they were used in boilers etc too.

[Arkless Electronics]

Open circuit at some points of the wiper and servisol etc made no difference. Binned it.