[sdiy] tempcos

[harrybissell]

Hi Ian (et al)

These are 1/6W @ 70C ... I suspect they are really about 1/4W body size
so
it should not be too much of a problem.  They have a larger size
available but
I didn't get a price on those... maybe I should check those out as
well...

I think the self heating might be on a par with the tranny pair... and
I'm one of those
who uses epoxy to add some mass to the whole system.

H^) harry

Ian Fritz wrote:

> At 09:05 PM 6/10/2004, harrybissell wrote:
> >from Micro-ohm.  1/6W 1Kohm +3500TC 5% for
> >$1.05 each in hundreds, $.85 in thousands
> >
> >The actual tolerance of TEMPERATURE coefficient
> >is not that great, but neither are their wirewounds ?
> >
> >I'm gonna get a hundred, but if a lot of other people
> >are in we could go for the 1000...
> >
> >Any comments on this tempco.  I've used a few
> >sucessfully. they are not as accurate as the KRL-Bantry
> >or the Vishay-Ultronix...
>
> Careful with that low-wattage stuff -- you can get into problems with
> self-heating.  I had trouble measuring the SMT guys because of them
> drifting around.
>
>    Ian