Variable resistor potentiometers for AR, Infinity, etc - replacements?

[HamboneF18]

For those who read this re: the AR pots, they are 0-16 ohm 25 watt, used as a voltage divider to adjust driver output of midrange and tweeter.





Used as a voltage divider. Tweeter circuit shown, AR-2ax:



A good substitute is this $10 unit, 20 ohm, 25 watt. As a voltage divider it will increase output at 100% setting, or allow AR setting’ or down to 0%. Open back, so just needs a simple hood to protect the wiper from the fiberglass batting. I used plastic cut from a 2-liter bottle.

 

[Leftspin]

For those who read this re: the AR pots, they are 0-16 ohm 25 watt, used as a voltage divider to adjust driver output of midrange and tweeter.

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Used as a voltage divider. Tweeter circuit shown, AR-2ax:
View attachment 2880734


A good substitute is this $10 unit, 20 ohm, 25 watt. As a voltage divider it will increase output at 100% setting, or allow AR setting’ or down to 0%. Open back, so just needs a simple hood to protect the wiper from the fiberglass batting. I used plastic cut from a 2-liter bottle.
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Interesting. What is the part number?

 

[HamboneF18]

I'm seeing the same white material, but it's on my screw heads also. I'm wondering if it's the zinc or whatever they coat the metal with to protect against rusting. I took a wire brush and screwdriver to remove it. The surface coating of the metal parts is now mostly missing.

View attachment 2880105

Spraying with clear polyurethane “paint” works to prevent corrosion, after removing the oxides. Back in 1998 I sprayed my heat pump control circuit boards to protect them, since they’re mounted outside in the weather. Had a technician out last week to give everything a checkup. Circuit board looked new!

 

[HamboneF18]

Interesting. What is the part number?

BTW, I didn’t use the knobs. I got the pots from Harfington. I see they’ve raised prices since I bought 4 a while back. (I removed the little tab under the nut.)