Welcome - I hope you enjoy reading my pages, which I've tried to make useful and entertaining for readers.
I used to work as a Technical Manager in the Broadcast industry, and have been a licensed radio amateur for more than 40 years.
This website mainly reflects my interests in radio communication, experimentation and construction, but a few other items may occasionally appear.
I'm one of the Admins for the SUWS WEB SDR - http://websdr.suws.org.uk/
I also operate a KiWi WEB SDR which covers 0-30MHz - http://southwest.ddns.net:8073/
This is connected to my Patented TC2M broadband HF antenna - http://www.tc2m.info/
Please don't hesitate to contact me, especially if you spot any errors or omissions.
Martin - G8JNJ
Active Antennas - Updated April 2018
1m HF loop antenna - Uses a novel tuning capacitor - RADCOM antennas column Sept / Oct 2010
G8JNJ ‘Fat-Max ® ’ HF Antenna - 6m to 40m - the poor man's Steppir
M3KXZ no-counterpoise antenna - Does it actually work ?
Slinky antennas - Compact antennas made from Slinky toys are likely to be poor performers
Solarcon / Antron A99 - How well does it work on other bands ?
Portable Vee Dipole - Uses fishing poles and a lighting tripod
Broadband Terminated Vee antenna - A travelling wave antenna using 9:1 Ununs & a 50 ohm terminating load
Rotary Washing line antenna - Various antennas using hardware from scrap rotary washing lines
Washing line wire reel antenna - A cheap portable antenna
Low Band Wire Antennas - Which is the best ?
HF Antenna Switches - Remotely select a Doublet, Tee or Vertical - for use with a 100w tranceiver
Multiband Wire HF antennas - Thoughts on the G5RV and similar designs
Better than a G5RV - the ZS6BK / G0GSV multiband HF antenna - External site
More information relating to ZS6BK antenna and matching section - External site
Problems with broadband transformers using Iron Powder Cores - why Ferrite cores give better results
6:1 Unun construction - Similar to Comet CHA 250 matching unit with less loss
Using Auto-Tuners - Some general information, Hints & Tips
FM on the LF Bands - How much spectrum does a Narrow Band FM transmission occupy
SSB TX audio equaliser - Published in Radcom February and March 2009
Boom microphone for Yaesu FT-857 / FT-897 & Icom IC-7000 - modify a cheap PC headset
Modifying Clansman Military Headsets - use with Yaesu FT-857 FT-897 Icom IC-7000
EMC & Amateur Radio - Updated February 2017 to include VDSL information
Switched Mode Power Supply - Why A CE mark Does not Guarantee a Quiet Power Supply for Amateur Radio use
All other miscellaneous projects can be found by clicking on this page link
- Manhattan or 'New Amsterdam' Style construction - Added Dec 2014
- 40m Antenna Shootout - Added June 2014
- Switched X dipole / Vee Beam
- Christmas Light - Vertical Antenna
Other items have now been moved to separate pages