Hello Jim & LF Group,
Thank you for your recent e-mail, I have seen your design in the recent past
but did not give it much thought, but I see from your comments & reading the
associated article http://www.picks.plus.com/software/LFtunemeter.pdf that
it will be a very worthwile piece of gear to construct. The only query at
the moment is regarding the phase meter (1mA-0-1mA), if I were to use a
100uA-0-100uA meter with a shunt would this cause any problems with your
design or maybe increasing the value of R2 would be acceptable, (I have this
meter already in my junk box), the 1mA meter for V & A metering is not a
problem.
Just had another thought, I presume that the device is to be inserted in the
coax feed prior to the antenna matching arrangement at the antenna end.
73
Gary - G4WGT
-----Original Message-----
From: [email protected]
[mailto:[email protected]]On Behalf Of James Moritz
Sent: 24 February 2004 12:27
To: [email protected]
Subject: LF: RE: RF Current meter
Dear Gary, LF Group,
The RF ammeter circuit in the LF handbook and on K0LR's web page uses a
current transformer to develop a voltage of a few volts across a load
resistor when the appropriate RF current is flowing in the primary. This
voltage is then measured by a simple diode voltmeter to indicate the
current. Sounds pretty simple then, but some pitfalls are possible with
an RF ammeter of this type...etc.
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