On the 5th of July, the club visited  the Anglian Water  Leighton Linslade Treatment Facility

There will be three stations set up in the Shefford A group: 23 cm with station manager Andy, 2M with station manager Stewart, and 70 cm, looked after by Steve and Brian.  The station managers plan to be available for the entire contest. The Shefford B station manager will be Terry running the 4M station till 10 PM on Saturday and then 6M on Sunday. As always, members are needed to operate.

This year there will be no paper logs!  All contact details must be entered directly into the electronic log running on the laptops.  Paul, who was heading the VHF/UHF NFD planning session pointed out that all entries must be absolutely correct in every detail or the entire contact will be lost.

Of course, there will be catering facilities on site for those who have signed the work schedule which includes setting up on Saturday, 7 July starting at 0900 UTC.  and packing up  on Sunday, 8 July 1400 UTC.

Members may attend even if they haven’t sign up!

Richard, G3NII started by explaining how the circuit worked and why certian components were used. He also explained why minor modifications were being introduced.  Ian, G3ORG followed by drawing a block diagram to show how areas worked with others.   Ian also had a test set up to demonstrate the effectivness of the project. Members then submitted their projects to be checked.

Paul, G1GSN who supplied the close up photos of the board says: The picture of the standing resistor is the new one – changed from 100 ohms to 33 ohms. Instead of mounting on the output (awkward), the resistor stands in the redundant hole of the noise switch. That moves just a little bit inboard and makes space away from PTT  input and the 12V supply. I thought it would be a good idea to show where the new C18(100pF) fits across the resistor R1(1k), hence the view of the solder side of the PCB.

Stewart’s presentation started with the ‘not so well known’ quote ‘I heard that… pardon!’ from an early 70s TV programme called ‘I didn’t know you cared’.  Stewart had a look back at the ‘good old days’ when there was a good chance that our transmissions might cause interference in a number of ways, while the interference we were experiencing was rather limited compared to modern times. Almost every day now, we hear of more ‘modern’ electronic wonders that cause more interference. So, what can we do about it.

Stewart outlined a systematic approach using flow charts to keep the search going in a logical fashion.  Apart from knowing where the interference was coming from and what to do about it, we learned that not all services are treated equally by Ofcom.  The three classes of protection status which saw the radio amateur as being ‘Protected from harmful interference’ gave us the feeling that we haven’t been completely left out of the protection process.

Of course, there are a number of ways we can deal with incoming interference ourselves; by removing the source, increasing the separation, using a separate receive aerial or by the use of filters and phasers etc. The receive aerials described  were loops, pennants and flags to minimise the received interference. All of which were described in detail.

At this point, Stewart decided it was time for tea and questions!

As you will have noticed there was no club meeting on  7 June 2012.

This was to give members a chance to be away for the Bank Holidays or Half Term break.

We will be ‘open for business’ next week, 14 June 2012, when Stewart will be giving his

presentation ‘I heard that, pardon’  – Sounds interesting!

For the record, here is Gary’s report after the DF hunt on the 31st of May, 2012:

There were only two that found me, the rest being out-foxed by the
terrain; and the troubles with equipment!

The winner was Steve M0DYR. Stewart G3RXQ was second.

I was using a 2.5m long fibreglass whip on a magmount, itself attached
to the middle of the roof of my car. The whip used to be the top section
of a ‘Shakespeare Super Big Stick’ CB homebase aerial. I had tested and
loaded it before, but last night the matcher struggled to load the
aerial and keep the SWR down. With the need to increase the transmit
power, I had to sit there with the engine running as my FT-757GX appears
to be very voltage sensitive and not happy down at 12V. Had I realised,
I could have packed my 13.8V PSU and an extension lead, and powered it
all from my friend’s flat.

So where was I? Right at the end of Lucas Way. It is quite confusing as
you reach what looks like the end where you see a block of garages. You
have to follow it around the 180 degree turn and walk back on yourself
to actually reach the end. Ironically, if people had walked towards the
little playground and looked to their left, they would have seen the
fibreglass whip giving away my location.

Here are the co-ordinates:

52° 2’32.15″N
0°20’8.11″W

24 May 2012

Our speaker has worked in radio for most of his life and told of installations around the UK and Europe. Topics covered were:

• Why is part of the FCO at Hanslope Park ?
• A simplified organogram of the Diplomatic Wireless Service.
• The origins of high power radio broadcasting in the FCO, Black Propaganda.
• A tour of the Crowborough transmitter site where it all began.
• How do listeners abroad know what is being broadcast and in what band ?
• Block diagrams to illustrate improved methods of generating a double sideband signal which led to big improvements in transmitter efficiency.
• A tour of the medium wave (648 and 1296 kHz) site at Orfordness.
• The origins of FCO broadcasting in the Middle East.
• The short and medium wave transmitter sites in Cyprus.
• The medium and short wave transmitter sites on Masirah Island (Oman), now relocated on the mainland.
• A brief mention of the FCO’s contribution to providing broadcast stations in such places as Tristan da Cunah, St Helena, and the Turks & Caicos  Islands

17 May 2012

The Spring mobile 2M Fox Hunt started promptly at 8pm. The fox was Ken and Ian Taylor who had found a spot in a new build estate which was only partially built but already had at least two families who had moved in. Fortunately, for the fox, the entrance was marked as having CCTV and security etc. so appeared to be not in use. But, as you know, appearances can be deceiving. While we were getting set up, a security guard came by, but just gave us a wave. Ian decided to have a word with him to explain what we were doing. The guard was amused but not bothered. The photo shows our location, but the Google Earth photo is old and the site is much more advanced than shown.

Transmissions on 145.550 were made for two minutes every 10. We were beginning to feel we had finally beaten all the fox hunters when, after some clues were given, Don and Bryan’s headlight came into view at 2108. They had driven only 6 miles. They were followed shortly, 2114, by Stephen and Brian who had driven 10 miles. Third on the scene were John, our secretary, and Peter at 2122 having driven a total of 13 miles. By this time, we had a good number of cars congregating in the gathering darkness. At 2124 Paul T. arrived; his mileage was 14 miles. Also arriving at almost the same time was newcomer Darren at 2126 (17 miles) who lives at Dunstable and seemed keen to know about our club and activities. David and Derek made a start, but didn’t make the finish.

My thanks to Victor for acting as ‘The Marshall’ gathering all the starting mileages and keeping the frequency clear between my transmissions. All the ‘fox hunters’ gathered at our usual watering hole for a drink and discussions about what and why they went the wrong way!

10 May 2012.

A video evening watching films from BVWS (The British Vintage Wireless Society) These short films were originally made as Public Service films; the first made by the Post Office is a snapshot of the then coastal wireless service operations. The story is a typical ‘day in the life of’ and centres on a couple of dramas at sea to highlight the importance of the service and it’s contribution to the fishing and shipping community. The film is believed to date from the late 1960s.

Following that, a story about EMI dating from the 1970s.  We saw the colossal size of the organisation at the time when the company was still manufacturing around the globe. The film was primarily a publicity article designed to promote and inform the viewer of the various activities, notably in the fields of recording, television, and CT scanners.

Another film appears to  have been made to inform GIs coming home to the USA after the war. Since many had experience in radio, electronics and radar, they might find a new career in the ‘up and coming’ TV industry.

A short film from Philips called ‘The Secret Writing of the Electrons’ told of Philips produced oscilloscopes but also showed a display of Cathode Ray tubes.

The final video wasn’t from BVWS but appeared on uTube. Called ‘Stairway to Heaven’ and showed a worker climbing a 1768 foot radio mast!  Just watching was enough to give one vertigo!

On 3 May 2012,  Dick told about his trip of a lifetime to New Zealand. Showing slides and video he told of his visit to the North and South Island taking in the major cities, mountains, and typical New Zealand scenery. The journey was via Los Angeles so on the return  they stopped off to tour the American west!           On the agenda was the Grand Canyon, Monument Valley, Bryce Canyon and Los Vegas.