WSPRing Across The Atlantic

May 7, 2009 by 30 Comments

wspr

Host of the Soldersmoke podcast, [Bill Meara], contributed this guest post.

WSPR is a new communications protocol written by radio amateur and Nobel Prize winner [Joe Taylor]. Like the very slow QRSS system described in a previous post, WSPR (Weak Signal Propagation Reporter) trades speed for bandwidth and allows for the reception of signals that are far below the level of radio noise. WSPR takes “low and slow” communications several important steps ahead, featuring strong error correction, high reliability, and (and this is really fun part) the automatic uploading (via the net) of reception reports — [Taylor]’s WSPR web page constantly gathers reports and produces near real-time Google maps of showing who is hearing who. The WSPR mode is very hack-able: [Bill Meara] is running a 20 milliwatt homebrew transmitter from Rome, Italy that features an audio amplifier from a defunct computer speaker pictured below. This contraption recently crossed the Atlantic and was picked up by the Princeton, New Jersey receiving station of WSPR’s esteemed creator, [Joe Taylor]. Continue reading “WSPRing Across The Atlantic” →

30’s Style Regenerative Receiver

January 9, 2009 by 11 Comments

radio

[Des] sent in this really cool writeup on building a Regenerative receiver using VFDs. Regenerative receivers are basically short wave radio receivers that use positive feedback to more finely tune the signal. Though they can be built with modern components, [Des] wanted to try to make something that not only looked like it was made in the 30’s, but actually used the same technology. He utilized some VFDs in various places where vacuum tubes were needed. After building, [Des] found that the unit performed very well, better than his authentic 30’s radio that he compared it with.  Those VFD’s seem to be everywhere recently. We did the story on using them as amplifiers, and and building display drivers for them too.