G 8 G M U   

On 26 February 1935 a radio receiver was taken, in a small van, to a field just south of Weedon, in fact Litchborough.To try to detect a Handley Page Heyford bomber. The bomber had been directed to fly through short-wave (49 metre) transmissions from the nearby Daventry radio transmitter. The Heyford was detected by the equipment in the vehicle & was tracked for some 9 miles. At the time known as RDF this was the 'Birth of RADAR'. Heyford Bomber    The Heyford was K6902 flown by Flight Lieutenant R. S. Blucke KX 50 Flatnose Morris with Eccles Caravan body. Mobile lab. 75 years the experiment was re-enacted in the field opposite on the site of the Birth of RADAR Memorial. A team comprising radio amateurs from the Coventry Amateur Radio Society & The Northampton Radio Club with many other people including the pilots of the aircraft who are all radio amateurs were successful in the re creation of the experiment. The independent witnesses included the farmer Helen Brodie and local villagers who gave a round of applause as the trace on the oscilloscope moved due to the reflections of the 2 metre signal from GB75RDF at Daventry. It is by the good grace of Helen (The Farmer) that we able to use the field. Her immediate reaction was to tell me, that her father, who owned the land 1935 always thought "It was great honour that this took place on my land".

"Daventry Calling this is Daventry Calling" This was the world famous BBC signature announcement of Empire Radio and World Service Broadcasts. On the 26th February 1935 The BBC Empire Service was the a tool of Robert Watson Watt & Arnold Wilkins. Using the the 10Kw 49 Metre shortwave transmission from Borough Hill Daventry. The signal used to 'illuminate' the Heyford bomber in order to discover the signal bounced from it in their mobile laboratory (van) at Litchborough. Our thanks to Arqiva for allowing access to the site & for the hospitality before & during the event People gathering around the vehicle just prior to the successful re-creation of the 1935 Daventry experiment at 12 Noon 26th February 2010 The Birth of RADAR Memorial Stone, with the replica vehicle & replica receiving antennas in the background. Note the pool of water in the bottom left. The field was very wet as indeed the field opposite was, reportedly the original vehicle did get stuck, we managed on the day with many pushing. We are most grateful to David Hooper for coming with his vehicle for the day.

Peter Grace giving his talk on RADAR history especially the Chain Home RADAR system, one of the highlights of the day. G1ORG was Tango 'd, not glowing due to radiation. It is thanks to Dave & the scouting movement that we had the superb tentage far this event. Model Chain Home Station with Watson Watt miniature statue in the foreground A close up of the Sir Robert Watson - Watt miniature statue, The full size version to be placed in his home town of Brechin by the Sir Robert - Watson Watt Society.

So how did we do it?   We copied the original principal. A signal on 2 metres transmitted from Daventry, received with a directional phased array built by SWL Howard (Now 2E0HOW). This signal fed to a vintage NDI HC1400 (pictured above) giving our dc output from the AGC line, applied to the Y plates of the oscilloscope (above right) which gave vertical movement of the spot.when an aircraft was present. The movement due to reflections from the aircraft - Simple!  (it is now, not so in 1935!!) The original experiment was carried out on the 49 metre short wave band. Using the BBC Empire transmitter at Daventry, hence this being The Daventry Experiment..

Without the pilots & aircraft we would not have had the same elegant result on the day. The pilots involved all radio amateurs G4FQI, G4FKK, G0TCA and G4FPN.   G4FQI came in the twin from East Midlands Airport, G4FKK & G0TCA from Biggin Hill and G4FPN from Wellesbourne near Stratford on Avon. All flying at their own considerable expense on the day for which we are all greatly indebted.

Putting GB4WWR on the air. A team from The Coventry Amateur Radio Society, Stuart M0CAR, Martin G1ZSR, Bob G4GEE, & SWL Howard (Now 2E0HOW) erecting the 80 metre antenna. It was raining here also! We were not deterred by the water on the field it saved watering the earth spike

Daventry Town Mayor Councillor Frank Voeten (also a pilot). Sending greeeting messages from GB75RDF at Daventry; under the watchful eyes of John G4CZB Amongst the Mayor's greeting messages was one to GB4WWR at Litchborough linking up both parts of the event..

Some of the 'Daventry team'. We are grateful to Arqiva for allowing the use of the Ex - BBC Borough Hill site from whence to original 49metre signal for the experiment was transmitted. Our re-creation was in the 2 metre amateur band. GB75RDF doing a grand job making contacts & telling people of the event. Also contacting other special event stations who were celebrating the weekend. Over the licensed period 24th February to the 9th March 2010 GB75RDF will have made in excess of 1000 contacts

The Birth of RADAR or the Daventry experiment was a closely guarded secret, not until after WW2 was the general public made aware about RADAR. It is the level of secrecy that makes this next part of the story truly amazing! The gentleman pictured left & right is Bill Purser G2AXO, he emailed me to say that he a young boy had actually ridden on his bicycle to Litchborough and given a report to a person he believed to be Arnold Wilkins. This quote from his email "I saw the aircraft and heard signals and cycled straight out to Weedon to give my report verbally" (Not only this, but his report was for 6 Metres.) Bill further stated, "I was listening on 50 Mcs to presumably a signal from Ray G3PZ which probably changed by reflection or blocking by the aircraft".   I wonder how many more interesting stories will be un covered?

It would not be an event with radio amateurs without beer. Frog Island Brewery in Northampton kindly produced a limited quantity of a specially labelled beer to commemorate the event. Considering it's rarity value this is a beer that will be kept and looked at rather than being consumed.

The Birth of RADAR Memorial near Litchborough. Unveiled on the 15th September 2001. by Nancy Wilkins, widow of Arnold 'Skip' Wilkins You Tube - Stone unveiling ceremony Our re-enactment took place immediately behind the Birth of RADAR Memorial. the original field in crop & muddy.The original location," in the field opposite" the memorial is seen in the video clip. Please click to offer help or to comment on the above RADAR page 1 RADAR page 2 G8GMU Home Page