Roger G3XBM's (Mainly) Amateur Radio Blog

Bernie G4HJW recently posted to the UK Nanowave Yahoo about some powerful red LEDs that he bought from China for just £2.80. A couple of th...

This morning I received an email from Steve, VE7SL, reporting on his experiments with VE7CA over a 2-way distance of 54km using red LEDs.  ...

Reading Stuart G8CYW 's article on the history of optical communications in the latest RadCom, I am considering repeating my recent NLOS...

Today I tried two experiments. Firstly a continuation of my tests with the loop and E-field probe out in the fens on 8.977kHz and then tonig...

12W red LEDs for optical beaconing This afternoon I ordered 3 off 12W red LEDs, called a Phlatlight PT54, from the USA. These were origi...

QRSS3 signal at 3.6km by non line-of-sight cloudbounce Armed with my simpler QRSS3/CW beacon (see earlier post) I did a very successfu...

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

G0EHV's lightbeam kit (from the UKNanowaves group photos) Today I joined the UKNanowaves Group which is dedicated to optical comm...

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...

The latest RSGB news reports that G8CYW and G8KPD have set up a new UK record for optical DX over a distance of just under 90km in NE Engla...

Until I read the webpage below I didn't know that the record for optical morse DX goes back to 1896 and was an astounding distance of 18...

This month's Practical Wireless makes reference to something called the Joule Thief circuit which allows a very nearly exhausted single...