On Sat, 01 May 2004 17:03:26 GMT, Jan Panteltje
wrote:

On a sunny day (Sat, 01 May 2004 14:19:59 +0100) it happened Paul Burridge
wrote in
:

Hi,

I have a spare RF signal generator that has an unmarked output from a
type of socket I've never seen before. What's the simplest way of
establishing its output impedance? I've had a few ideas but no doubt
someone out there will know of something better, since I always seem
to end up making unnecessary work for myself.
Any suggestions?

Load it with 50 Ohms, and measure output voltage, remove load and measure
again.
If it is half, it is 50, else do the math.

Or double, presumably. :-)
Well there you go; I knew there must be a more elegant solution to the
one I dreamed up which basically involved taking a spread of 10 carbon
resistors of from 10 - 1000 ohms and measuring the applied voltage
across each, then arriving at power transferred in each by V^2/R;
drawing a graph of the results and finding the point of maximum power
delivered.
--

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