One of the problems is that when you measure the resistance to ground in a circuit that contains solid state devices, the value can vary widely because of the meter you are using. Different makes of DMM's use slightly different voltages for the ohms sense and that can cause widely varying readings in the resistance in a "normal" circuit. That's because often the value of resistance you are seeing is not the value of several resistors, but is instead a slight forward conduction through junctions of transistors, and diodes.
Also, that is why it's so important to only use a meter designed for solid-state gear. Many older "VOMs" use sufficient voltage and allow sufficient current to destroy solid state devices. But even among the DMMs designed for solid state circuits, the values reported when "looking" through junctions in IC's or transistors can vary widely. Add to that the desire to be sure that when the book says "greater than" (>) there follows a value that NO DMM is expected to show less than if the circuit is correct, and sometimes the actual value your DMM reports will be orders of magnitude larger. For example, your DMM may indicate several megohms when the book says ">100k ohms" Ron AC7AC -----Original Message----- > Perhaps these questions come from those not familiar with the 'greater > than' symbol (>) - I can only guess. Or from people thinking it's "too much" greater than - I did have that thought the first time I saw > 100 k and measured a few M. I decided it was ok and carried on... _______________________________________________ Elecraft mailing list Post to: [email protected] http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: [email protected] http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com
