Roger G3XBM's (Mainly) Amateur Radio Blog

Waverley Rd, Kingsbridge, Devon, UK My interest in light-beam communication goes right back to the 1960s when an old school friend and I...

There is a nice precis on Wikipedia about this. It is some time since my health has allowed me to do experiments with light. My special inte...

Well, this was an interesting evening. Just after teatime I noticed 50MHz was open with some strong Es signals from Europe. A few stations w...

With my wife manning the TX this afternoon and pointing it out of the landing window we managed a daylight speech test today with 100mm opti...

This morning I took a step further towards making a complete 481THz lightbeam transceiver by breadboarding and testing a simple AM transmi...

G4HJW received on 481THz over an 8.63km non line-of-sight path Bernie G4HJW was 20dB S/N in 0.67Hz bandwidth earlier this evening at m...

Well, guess what, I am a year younger (amateur radio wise) than I thought. Having looked up some old RSGB Bulletins this evening I see that ...

SpectrumView 0-24kHz displays of waterfall and spectrum Looking around for useful (free) software to help me with VLF and lightbeam test...

TX beacon optics This morning I bought a length of 110mm waste pipe from the local Plumb Centre shop. It came in a 3m length and ...

670nm receive head and converter to 80m Today I did some further light beam experiments, this time using a 25kHz modulation signal on th...

G8AGN/P and G0EWN/P achieved a 111km speech QSO on optical communications using 0.5W red LEDs and Fresnel lenses on April 6th 2011. Brillian...

Before I became a radio ham, a friend and I had our first phone wireless QSO using a small torch bulb modulated with a couple of germanium t...