bad precision pot?

[Martin Czech]

I've read somewhere that precision 10 turn wirewound pots have problems.
The slider seems to stick on the windings, that means problems with
resolution.  And it was said that mechanical shock or vibration would
change the value.  The author claimed that he would rather prefer ordinary
pots, maybe two, one for coarse and one for fine.

I was sceptical.

I took a 10 turn 10k Burns with 10 turn display/knob for my test
oscillator.  I doubt that I get better resolution with a carbon or
other type pot.  I tryed also reasonable shock and vibration (finger,
pencil, screwdriver) and I couldn't find any change of value (even if
the mechanical break was inactive).

So, I came to the conclusion that these guys are expensive, but worth
the money.  Especially for analog coefficents.

As they are wire wound they should have high inductance, however.
Won't harm for dc control voltages.

Any other observations?

m.c.