3 ms·
I used the WSPR protocol to send a message from San Francisco to Georgia using a 250 milliWatt transmitter, operating in 20m. It sends tiny messages (current l
by blendo 2y ago
I used the WSPR protocol to send a message from San Francisco to Georgia using a 250 milliWatt transmitter, operating in 20m.
It sends tiny messages (current lat/long, transmitter power, and your call sign) with so much error correcting code that each 50 bit message takes a minute or two to transmit.
https://en.wikipedia.org/wiki/WSPR_(amateur_radio_software) https://en.wikipedia.org/wiki/WSPR_(amateur_radio_software)
It’s the only time I’ve used my General class privileges.
- chillingeffect 2y agoOmg reading the wiki for wspr i thought i saw a typo "630m" but yup, ~430 kHz, wow. What antenna did you use, a quarter mile dipole? ;)
- wl 2y agoWikipedia is just being weird by using an MF band in its example. Most WSPR is in the shortwave bands, which can use large antennas, but not THAT large.
- swalberg 2y agoHams have privileges on 2200m, too! At those wavelengths people are using big loading coils. Saw a video last week of a guy in Alaska with a sizeable loop in the trees and was putting in about 1 KW to get 1W EIRP. WSPR is all over the ham bands. There's people making relatively small, hydrogen filled balloons and trying to see how long they will stay alive. They're using WSPR on 20M to broadcast their telemetry (search for Traquito).