David wrote:
Hi,
What would anyone recommend for measuring SWR on a system that has a low
power transmitter (20mW) ?
My meter has lowest range of 3W FSD. I do have a digital power meter and
directional coupler, would it be best to manually measure fwd power and
reverse pwr and calculate SWR ?
Thanks in Advance
Regards
David
20mW is definitely pushing it. QST published a QRP SWR meter at one
point that might go down that far with work. I use an RF noise bridge
and a receiver for establishing feedpoint impedance -- that may be the
way you'll want to go.
IIRC the bridge design came out of "Solid State Design for the Radio
Amateur" by Hayward and DeMaw. I think it's basically what MFJ sells,
only they wrap it all with a fancy computerized controller.
--
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
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