[volt-nuts] Anyone know how to make stable inductors?

[Dr. David Kirkby (Kirkby Microwave Ltd)]

I was looking to make some inductors that I can use as a sanity check for
my HP 4284A LCR meter. I don't too much care what their values are, but I
want them to be stable with time. Any suggestions about the best way to
make or buy them? I'd like values in the range of 1 nH to 100 mH.

The LCR meter has 4 terminal Kelvin connections, with 4 x BNC sockets on a
22 mm pitch.

The meter is at Keysight at the moment being calibrated, along with a free
software upgrade they are kindly providing. So I'd like to measure some
inductors when it comes back, and track their values over time, to see if
the meter is drifting.

The meter covers 20 Hz to 1 MHz, and has a basic uncertainty of 0.05%, so
ideally I'd like to keep inductor changes to less than 0.005% over a year,
so the inductor is an order of magnitude better than the meter. Maybe that
is not practical. As I say, the absolute value is not important, since I
only want a comparison.

The calibration costs on this meter are not too bad (£207 GBP), but the
calibration interval is 6 months, which is a bit annoying. I'd rather not
be sending it off every 6 months if I can satisfy to myself it has not
drifted too much. Luckily I don't need to satisfy anyone else.

Dr. David Kirkby Ph.D CEng MIET
Kirkby Microwave Ltd
Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Essex, CM3 6DT,
UK.
Registered in England and Wales, company number 08914892.
http://www.kirkbymicrowave.co.uk/
Tel: 07910 441670 / +44 7910 441670 (0900 to 2100 GMT only please)