Corby Just a 1 cent thought that may not apply or be accurate. C-fields are current sensitive, so if they are wound with copper wire, any small change in their temperature, even when temperature controlled, could have a effect much greater than 1PPM on that current when driven from a fixed voltage thru a resistor. Does anyone use current drive? ws ***************** Corby posted: Attached is the schematic of the C-field supply. Cheers, Corby

-------- In message <5AC3D7F0C1F14BAB8B7BE4A552034FCC@dell370>, ws at Yahoo via time-nuts writes: >C-fields are current sensitive, so if they are wound with copper wire, any >small change in their temperature, even when temperature controlled, could >have a effect much greater than 1PPM on that current when driven from a >fixed voltage thru a resistor. > >Does anyone use current drive? The standard circuit is current drive... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk@FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence.