Jay, W5OLF has produced a new version of his WSPR beacon (see photo). It is simpler than his earlier version, the WSPR-AXE-CW.
He writes:
"I have finished my WSPR-Snake stand-alone transmitter. The snake name is because it is programmed in the ‘Python’ language and, as with the WSPR-AXE-CW, the repeated random 2min intervals on the spectral display to me look like the trail of a snake. Differences between it and your‘s are that it only puts out 375mW (on 10M) but runs off of USB 5V sources. One can plug it into the common wall cell phone charger or into the cell phone recharge batteries they sell. It uses the Adafruit Trinket micro board which has a 3.3V regulator on it for the VCO. Like yours you turn the PA off when not actively checking propagation and you can even put in a switch to turn the VCO off (reducing standby current to 10mA). That allows transport (say backpacking) without loosing the precise time you set back at the shack. Speaking of the precise clock, this version uses the clock circuit for both WSPR symbol timing (exactly) as well as 2min interval timing; expected drift when set - and the crystal aged - is about 0.5sec per month. Otherwise, I use the same single 2N7000 for the final in a class-E, high efficiency, design. "
