One of the secrets of QRP is you MUST have either a resonant antenna or antenna tuner. Why? Because if the rig sees any sort of SWR, most will cut back on the power. This is very confusing for newbies. They put in a SWR/Watt meter in line and see that while the power might be down to three watts or so, the SWR appears perfect. And, try as they might they can’t seem to work anybody.
Well if the antenna isn’t trimmed for where you are on the band, you’re not going to get full power out and when you’re talking five watts to play with you want all the power out you can get. The false SWR meter reading usually happens as the meter hasn’t got enough sensitivity at these low power levels to report accurately.
The result is guys go around saying QRP doesn’t work!
Sure it works. I proved it by working three guys during the CQ WW WPX CW contest using 300-milliwatts into a dipole.
A 100-watt rig, especially one with an auto-tuner, can allow just about anyone the ability to work other stations regardless of the antenna. A kilowatt amp, so long as it doesn’t melt improperly solder connectors, can ensure you’re loud as well. But a QRP station, especially an amazing QRP rig like the FlexRadio 1500, into a properly trimmed antenna can compete with most of the 100-watt setups out there.
Like I said, I managed to work Puerto Rico with my $250 R40/20 running four watts into a PAR end-feed antenna (It’s essentially a coaxial sleeve dipole which uses the outside coaxial shield as a random length element working against the centre conductor which is cut to a resonant length for the desired frequency. Not as effective as a properly cut dipole but has the advantage that only one end needs to be high in a tree for it to work.) while sitting in a chair on our front walkway.
So now the backup station looks like this:
I’ve got a Drake R8 working as receiver for the Tuna Tin II 300-milliwatt transmitter and the Ten Tec R40/20 running into the LDG-Pro 200 autotuner (remember what I said about resonant antennas) and I’ve got my Diawa 15/150/1.5K SWR/wattmeter in line to my Ameritron five-position antenna switch (Explorer Yagi with 40-meter loaded dipole; 160/80/40/30 dipole; 80/40 Alpha Delta dipole; G5RV-JR dipole and Butternut-type HF-6V vertical; and 160-sloper antenna still be affixed.)
And then of course there’s the main rig a FlexRadio 1500 which at $600 is the best buy in all of Amateur Radio as it comes with a panoramic display built-in and, according to Rob Sherwood, one of the best contest receivers on the market. (Yeah, yeah you need a computer but you’d have one anyway just to run the logging program.)
Next project is to trim the PAR antenna for 40 meters (works great on 20) and build the BLT QRP autotuner – remember what I said about resonant antennas 🙂