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Thread: Having difficulty interfacing a current sense resistor
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face BY : Mike Kendall email (remove spam text)



Who cares where Sanjay was trained?  I've  met some real morons in my day
that hold college degrees from reputable colleges.
Aren't we talking about the sensitivity of the circuit used to make the
measurement and the power dissipation/efficiency of any impedance
transformation device used.  A traditional analog meter uses 10kohms/1volt.
This why the older SAMS circuits gave voltage reading points with the "load"
of the meter taken into account.  A modern digital multimeter (DMM) has a
sensitivity of 10megaohms/1volt, I've even seen one with 20mohms/volt once.
Another classic example is RF current meters in transmitters.  Certainly an
RF current meter inserted in a transmission line path will not require 5% of
the radiated power.  If this was so, a 1.5kw transmitter would lose 25watts
to the meter and it would require a small heatsink. If the analog meter
movement was replaced with a digital readout that had an active power
supply, would it suddenly require 5% of the radiated power?  I've never seen
a heat dissipating RF current meter in my life.     The earlier idea of
winding a transformer seems to have much more merit to  me than to give up
5% of the power.
> Hi Sanjay, sorry I don't know where you were trained,
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> > {Original Message removed}
<000c01c11828$03e85200$0101a8c0@pavilion> 7bit

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