Here is a DIY guide to making some lab standards. It is detailed with some component values.
http://nopr.niscair.res.in/bitstream/123456789/4848/1/JSIR%2065%286%29%20510-513.pdf On Wed, Aug 19, 2015 at 8:48 PM, Dave M <dgmin...@mediacombb.net> wrote: > Here's a paragraph from IETLab's web site on how their inductance > standards are made: > > "Each standard inductor is a uniformly wound toroid on a ceramic core. It > has a negligible external magnetic field and hence essentially no pickup > from external fields. The inductor is resiliently supported in a mixture of > ground cork and silica gel, after which the whole assembly is cast with a > poƫting compound into a cubical aluminum case." > > Sounds like their objective is to isolate the winding from as many > external influences as possible. Of course, the same couild be said of any > physical or electrical standard. > > Cheers, > Dave M > > > > > Dr. David Kirkby (Kirkby Microwave Ltd) wrote: > >> 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) >> > > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. > _______________________________________________ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.