DIRECTORATE OF TELECOMMUNICATIONS
Special Services Memories (1980)
By: Dave McKay
My first dealings with The Directorate were when I was a member of the Ministry of Defence Police special escort group. Because we provided an armed police escort all over the country we required to be able to communicate with many Home Office Police forces.
As a result I dealt with CCE at Harrow during the early 80's. As I recall it was behind the HMSO building in Harrow. We used Pye Whitehall's at this time and in order to work the forces along the route we had to carry three sets in a rack behind the drivers seat in a Range Rover. This proved to be interesting because there were only two control boxes mounted between the front seats, when the boxes needed to be changed over the driver had to move his seat forward and the radio operator in the back had to change the leads over. This was OK if the change was possible during a stop but interesting if it had to be done on the move.
The sets were designated "A" "B" and "C" for normal use and then there was a "D" set which was for special jobs. These were crystalled as required for these jobs and we had to take them to CCE for this to be done.
We also had a job that required the use of a train and the set used was an ART177, which gave access to most Police VHF main scheme radio channels in the UK.
This was a wondrous piece of radio kit after dealing with the Whitehall especially to the Radio amateur in me. Even though it was early logic design they were remarkably reliable. The fit was done by Racal from Bracknell due to the HF system we also used. The usual thing that went faulty was the special tuned slot antenna that the Racal engineers had installed because of the limited gauge on the carriage for antenna clearance. It was tuned to 100 MHz Rx and 82 MHz Tx by means of switched matching circuits.
However, due to the hostile environment, it would often de-tune and give poor Tx and Rx performance. The Racal engineers fixed it a few times but it was so unreliable that I eventually took a quarter wave mag mount whip tuned to 82 MHz Tx. After one job the Racal engineers came to fix the slot antenna and asked how we had managed to get any comms using a quarter wave whip tune to 82Mhz when the Rx frequency was 100 MHz It took quite a bit to convince the guy that a quarter wave antenna like this was quite broad band on receive and the normal fit to almost every Police vehicle in the UK. But then he was also the Guy who when faced with a Pye Reporter that would intermittently blow the supply fuse told us to keep fitting a bigger fuse until the fault became permanent on the set……...one solution I suppose.