The resistance readings may vary widely depending upon the polarity of the leads attached and the individual DMM used, especially when there's a transistor or diode junction somewhere in the circuit.
Also, most DMMs read "INFINITE" whenever the value exceeds its maximum range. That can be a few megohms for some DMMs and many megohms for others, so it's not possible to know when the builder will see "2.6 megohms" or "INFINITY" or, equally disturbing to some builders, "OVER RANGE" which simply means the meter can't measure it. At the other extreme are typical permissible variations in the accuracy of DMMs and in the tolerance of the components in the circuit that affect readings. Those things also conspire to make it virtually impossible to try to establish "typical" resistance values in a great many situations. Besides, just what is "typical", within 10%, 50%...? So values are chosen that, if the circuit is correct, the vast majority of DMMs display measurements that agree with those shown in the manual. Some will be closer to the limits given than others by orders of magnitude, but as long as the reading agrees with the manual you're okay. If you have a reading that simply "feels" close, try reversing your test leads and see what happens or, if you have one, try a different DMM. Ron AC7AC _______________________________________________ Elecraft mailing list Post to: [email protected] 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
