David, G8UOD began by saying his talk would cover the period between WWl and WWll, but it was pointed out that, although the country was not involved in a World War before 1939 there were numerous smaller conflicts involving Great Britain. During this time progress was being made in communications, and by 1933 the first of the ‘numbered’ sets was in use. Of course, it was called Wireless Set Number One.
At the start of WWll numerous sets from the first war were still being used, most likely due to the effects of the depression. However with the onset of WWll the Royal Signals quickly organised their ever growing numbers into various groups of command. In 1939 they totalled 43,332 persons which grew to 150,990 by 1945. All aspects of communications were eventually covered from laying land lines to mobile communications, cryptographic, and even deception transmissions as cover for the D Day landings.
Photos from Wireless for the Warrior http://www.wftw.nl/wsets.html
A good club turnout came to hear Richard tell about the UK’s Heritage Railways.
Richard is very knowledgeable of the subject as well as being enthusiastic. His slide presentation detailed the results of various rebuilding projects from narrow gauge to full size engines. All done by volunteers who not only rebuild but help finance the projects through fund raising. To make matters more difficult, almost all of the restoration is done in the open air! Restorations need to be covered during bad weather and heavy lifting equipment has to be hired in when things need moving.
The engines which have been bought from scrap yards where they have been rusting for the last twenty five years are now looking like new and running on their own rails. A feat that many thought could not be accomplished by volunteers.
As the winner of both the Weekend Special and the Major Project sections of the contest, Don, G4LOO spoke about his projects.
The Weekend Special was a self imposed challenge to build a high Amperage power supply for under £50. Don provided a cost breakdown which included numerous items purchased on the internet. The main power was supplied by the Dell Poweredge,
Server supplies. While many are listed on the popular auction site, the cost of shipping can be a deal breaker! Two were found that met the criteria and were incorporated into the twin 12v, 2x 47A supply. Don explained how a voltage nearer to 13.8v was obtained and
how over voltage and power was controlled and monitored.
The idea for the Major Project came during Don’s visit to Friedrichshafen where he saw a PCB for build a switching control for six antenna inputs to two rigs. Don build this unit but then decided he would like ten inputs to two rigs and set about designing one. After producing his own PCB, Don used 36 relays to control the ten inputs and also the inputs from his Four Square antenna. Measurements show the connection isolation to be equal to or better then commercially manufactured units.
Victor, who won the Kit Competition, was unable to attend on the evening and will present his story of building the ‘PIXI’ at a later date.
Don’s first talk about Utility Listening was back in 1990 when he described the Hoka Code 3 Data Mode Decoder. At that time there were many different modes which are, for the most part, no longer used.
Since that time, many of those who made the transmissions have changed to satellite communications. However, now it is realized that satellites can be vulnerable as well as costly. Some Civil Authorities and the Military have been migrating back to HF communications. The use of complicated software negates some of the shortcomings of HF drop-outs and the overall result is still reliable and much cheaper. While still using satellites, the HF communications provide an effective back up.
Don demonstrated the latest decoding software and played several recordings of transmissions using modern modes of modulation. Although much is known about the parameters of the transmissions, most of the results are encrypted. There are, however,
some transmissions which are not. They are mostly weather related and some news services.