Lloyd, thanks for the informative (and well produced) video. I've done similar experiments using the same bridge. Have you come up with a way to calibrate the power without expensive equipment? 73, K3FLN
Hi Chuck. Thank you for your positive comment. I don't know how this would be done in a lab, but I measure peak-to-peak RF voltage with an oscilloscope, then compute RMS power as p-p voltage squared divided by (8 times the load impedance) --footnote 2 at www.lloydm.net/Demos/swr.html.
Lovely video, Lloyd! Timely as well, because I've just received a V1.5 bridge from W8DIZ at Kits and Parts to incorporate it into a QRP transceiver. The clones of Diz's boards don't have the Kits and Parts URL and often the version number overlaps the "SWR Bridge" text on the board. IMSAI Guy got a clone - MaWBiQuOhnI (
Lloyd, thanks for the informative (and well produced) video. I've done similar experiments using the same bridge. Have you come up with a way to calibrate the power without expensive equipment?
73, K3FLN
Oops, posted before I read your document.... nice write up too!
Hi Chuck. Thank you for your positive comment. I don't know how this would be done in a lab, but I measure peak-to-peak RF voltage with an oscilloscope, then compute RMS power as p-p voltage squared divided by (8 times the load impedance) --footnote 2 at www.lloydm.net/Demos/swr.html.
🙂👍
Lovely video, Lloyd! Timely as well, because I've just received a V1.5 bridge from W8DIZ at Kits and Parts to incorporate it into a QRP transceiver.
The clones of Diz's boards don't have the Kits and Parts URL and often the version number overlaps the "SWR Bridge" text on the board. IMSAI Guy got a clone - MaWBiQuOhnI (
Many thanks and Fair Winds! -Lloyd (WA4EFS)