Which damping resistor pot?

[autitch]

I’m attempting to put together a variable damping resistor circuit for a concentric coil I’m putting together for my Minelab GPX 5k PI . I have found this simple circuit which is what I’m looking to make. I was wondering what type of pot resistor is recommended. As I don’t have much experience with pot resistors there are several types I’ve found available single turn, cermet, wirewound or plastic. Which of these would be better suited for the application. I’m assuming 1W would suffice.

AuTitch

[waltr]

I’m attempting to put together a variable damping resistor circuit for a concentric coil I’m putting together for my Minelab GPX 5k PI . I have found this simple circuit which is what I’m looking to make. I was wondering what type of pot resistor is recommended. As I don’t have much experience with pot resistors there are several types I’ve found available single turn, cermet, wirewound or plastic. Which of these would be better suited for the application. I’m assuming 1W would suffice.

AuTitch

I use any of the smallish cermet single or multi turn pots. Since the pot is in series with the 200 Ohm and then parallel with the 2k Ohm resistors it does not 'see' much current (power). So any NON-inductive pot will be fine.
Do NOT use wirewound since these have high inductance and will effect the coil's collapsing field.

[autitch]

Thanks Waltr for clearing this up. I'm glad I asked the question as I was thinking of using a wirewound pot.

AuTitch

[autitch]

Just wondering if the resistors should be the 1W type or would 0.5W resistors suffice.

AuTitch

[homefire]

One Watt is good. .5 would work .

[waltr]

One Watt is good. .5 would work .

Yep, I use 1/2 W and have even used 1/4 W for short periods.

[autitch]

Thanks Waltr & homefire.

AuTitch