Jim, W1FMR asked: What is the lowest capacitance value you can measure with the popular DMMs ? (in picoFarads ?) DMM specs do not spell out what the minimum capacitance is..
--------------------------- My Radio Shack DMM will accurately measure capacitance as low as 2 or 3 pf. It has a parasitic capacitance of about 111 pf, but that's not a serious problem when working with small capacitors. I simply subtract the parasitic capacitance from the reading (113 pf - 111 = 2 pf). The meter has sockets for capacitor leads to avoid variable parasitic capacitance from the test leads. I've checked it for accuracy with values at low as 2.2 pf. It will work with the test leads attached too as long as I'm careful to lay the leads out so they don't move around. I've measured the value of caps I can't plug into it easily (e.g. a large variable cap) by arranging the leads so they are close to but not touching the cap and noting the parasitic capacitance. Then I touch the leads to the cap and note the change. I can't guarantee how other DMMs will react, but since a relatively small number of special-purpose I.C.s are used in virtually all DMMs, I'd expect other DMM's in its price class ($70) to behave much the same. Ron AC7AC _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
