Re: What are you QRP guys using to measure power?

Arv Evans <arvid.evans@...>


Should be easy to do.  Just a well designed Stockton bridge to sample 
both SWR and PWR, then use an Arduino ADC input to read volts and 
convert that to show amperes FWD, amperes REV, watts FWD, and 
watts REV.  Could also do some fancy things like output for limiting 
RF PA drive if the reflected power were excessive, and maybe even do 
rough frequency measurement by adding a divide-by-n ahead of one 
of the digital input ports.  Once you have the RF sample, the rest is 
just software.


On Fri, May 29, 2020 at 4:01 PM Mike Besemer - WM4B <mwbesemer@...> wrote:

I think we need a QRP-Labs meter – 0 to 5 watts!





From: [] On Behalf Of ajparent1/KB1GMX
Sent: Friday, May 29, 2020 5:39 PM
Subject: Re: [QRPLabs] What are you QRP guys using to measure power?


I use...

QPSA, a Steve Webber design for over 10 years ago also SWR/frquency counter/aux
audio amp.

DL5NG terminated diode mount (up to 10mw or so, with calibration table.

A dummy load based on caddock resistors (25W) and diode for the
10mw to  20W range HF and calibrated.

Bird Model 43 throughline watteter. Large number of slugs for it.
Loads:  Bird Dummy load (100W), Heath cantenna for higher power.
A lower power 100W pint-enna  (high power (caddoc) resistor in Pint can.

RIgol DSA815T or HP8568B SA with 30DB 50W power attenuator (narda 7768-30)
Also a Bird 50W model similar.

All in cal.

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