I’m not too diligent about documentation – most of the fun is in building and experimenting! Nevertheless here are a few ideas from the GM4WZG stable.

El Peregrino

El Peregrino

From being a child I was enchanted by the idea of hiding things away in secret books. I guess I loved books, and I loved secrets ! When the EAQRP Club (The Spanish QRP Association) published “The Pilgrim” I thought it would the perfect vehicle for a nice little hidden “spy” transceiver.

It operates on SSB on 17m, has a built in ATU and a built in microphone/PTT.

FT817 Auto-tuning Magnetic Loop

I am very impressed with magnetic loop antennas and thought it might be nice to cross my interest in embedded systems with some amateur radio. The mechanical nature of the project lent itself to shooting a video – so I made one.

Airplane Wi-Fi

An embryonic project born out of a serious need. Coupling an Ipad in a light aircraft to a ground station that tracks position via GPS to maintain a directional antenna pointing at it. Allows the pilot to send high res images of a search area back to ground without having to land. Amateur Radio helping Amateur Aviation to search for vulnerable missing persons.


BOB – The mystery project ! To be revealed after publication in the world’s leading Amateur Radio journal. Watch this space….


Here is a Lora transceiver as loved by IoT fans – but one with a difference. Etalia has a power output of 1W which is QRP by amateur standards, but a heck of a lot of output for a Lora module. Coupled with a receive sensitivty of -137dBm and a built in web based messaging system, Wi-Fi and built in GPS this device was designed for RAYNET emergency use.

Those of us who are licenced radio amateurs have the privilige of being able to use higher power like this legally.


A useful little project for those that require battery backup for mains powered equipment. It started out as an investigation into applications of Smart Diodes. In essence, these are diodes which have an almost negligible forward voltage drop.

BiPower uses a pair of smart diodes to provide reverse polarity protection and battery backup to equipment driven from 12V mains power supplies.

VDSL Filter

It wasn’t the best of news that a neighbours internet outages coincided with GM4WZG activity on 40m. Some investigation and notching out of the 40m band from the copper VDSL feed not only solved the problem but led to a huge improvement in broadband speed for the neighbour. Not so much a project, as a story…..