Next RADARC club meeting is Thursday 25th May at Woodford Park Leisure Centre, Woodley, 8pm.
Our very own Steve Coleman G4YFB presents brief history of radar from the beginning, through the ‘hardware’ stage to the ‘software’ stage of modern radar.
Refreshments to be served as usual.
Folks,
Peter Butcher is with us on Thursday 11th May for the next club meeting.
Venue: Woodford Park, Woodley as usual.
In his own words:
“Communications between the Emergency Services, Police, Fire and
Ambulance have always been a problem. Complete inter-operability has been an elusive goal since the 1960s, so what has changed?
Three disasters; The East Coast Floods, the Isle of Wight Air Crash and Lockerbie prompted the Home office to take action and a set of
frequencies was allocated for the Emergency Services to allow
inter-operable communications. Planning rules were established and the question arose as to how many radio sites would be needed for a network to cover England and Wales.
A contract was awarded to Racal Radio in 1993 to calculate that number and I worked on that report as a Consultant, having recently retired from the Racal Radio Group.
The paper describes that work in detail, showing how time consuming and difficult propagation predictions were in those days and how two
different methods; manual calculation and early computer-aided
prediction gave sensibly the same results.
How that information was used and where we are now gives an interesting insight to government. After some long winded correspondence, the Home Office gave me permission to re-publish my historic report and added their version of today’s position.
Basically this paper is an historic archive of how things were and how
much, or little, things have changed!
Peter Butcher.
April 2017”
A big thankyou to George M0GXB for helping organise this one.
Refreshments to be served – or perhaps more accurately to be made
available. Audience participation may be required to make them happen.
There will be many, many biscuits. Some of them in date.
Looking forward to seeing you there.
73
John
G4RDC
Folks,
At our next meeting we welcome Prof. Mike Underhill G3LHZ to tell us all about magnetic loop transmitting antennas including the latest research. He will bring a selection of loops.
Venue: Woodford Park, Woodley, 8pm as usual, Thursday 27th April.
Further, Mike will address fundamental questions about antennas in
general.
Mag loops offer interesting possibilities where space is at a premium –
a number of them we are hoping will fit in the tea room at Woodford
Park.
Also, if extreme volts and amps are your bag – this is definitely one
for you. I’m no expert (Rael is, M0RTP) but the tuning caps need to be
specially designed to handle the high voltages (often involving vacuums) and the loops themselves need low resistance.
Tuning of said caps offers challenges for micro controller/computer auto tuning so there’s something for Arduino/Raspberry Pi enthusiasts etc. – indeed Rael has done quite a bit of work here.
Refreshments to be served as usual.
Looking forward to seeing you on Thursday.
Many thanks to Rael, our own mag loop exponent, for helping organise this meeting.
cheers
John
G4RDC
Thanks to Peter Blair, G3TLF;
He has passed us some useful links from his talk last week about EME.
We hope you find these useful and informative!
http://www.df2zc.de/newsletter/ 2m Newsletter
http://www.nitehawk.com/rasmit/em70cm.htm 70cm Newsletter
http://www.nlsa.com/nets/moon-net-help.html Reflector
mailto:moon@moonbounce.info Reflector
http://www.physics.princeton.edu/pulsar/K1JT/ WSST
http://physics.princeton.edu/pulsar/K1JT/Hbk_2010_Ch30_EME.pdf ARRL Handbook EME Section
http://www.moonbouncers.org/ Good technical info
http://www.qsl.net/dk7zb/ Great HB Yagis that work
http://www.hb9q.ch/hb9q/ HB9Q logger
http://www.chris.org/cgi-bin/jt65emeB N0UK logger
http://www.w1ghz.org/antbook/contents.htm Dishes
http://www.vk3um.com/software.html Planner, Analysis++
Also if anyone is intending on getting involved in EME we would love to hear about it! You could even write a short article to go on this website.
There is a wealth of knowledge within the club so just come along and ask!
On the 11th of march I bought a Simoco SRM9000 from Mike G4CDF. (Thanks Mike!) I finally had a 4 meter rig and he also let me borrow a 4m loop to get me started until I could make my own. I was pretty much working to get it all setup as soon as I arrived back home.
First question when putting any amateur station together is of course how on earth will this all go together and where can I put it?!
The antenna itself is not small and would not be the kind of thing I can just hang in my window. It also has a pole fixed to it for mounting vertically with a horizontal spacer between it and a mast. This made things more difficult as it could therefore not just be laid down on a first floor roof ridge which is close enough to my shack. Instead I settled for persuading my parents to let me stick my military fibreglass mast up on the corner of the house. Amazingly, it blends in quite well and just looks like a piece of guttering down-pipe that is rather small…. Oh and it also has a large chuck of metal hanging off to one side!!
So I have an antenna sorted and a mast for the antenna to go on. I setup the radio connected to the power supply that I have running my other radios on the desk and it immediately sprang to life. Great… I have a radio, an antenna, a microphone and speaker and power. I knew I was missing something.
Aaaaah…. Coax!!!
Next problem – how to get coax into the shack without drilling holes in the wall or doing anything else that seems to annoy my parents! So here is my solution:
It got a little cold last night because the window is now open just a crack for the coax to come through so i enlisted the ever useful duct tape method!!
Finally I was ready to get a QSO on 4m so I then experimented with all the buttons and I think I hit scan and heard Alison G8ROG doing a test. I quickly replied and sort of knew that I would manage to contact her given we are just across the valley from each other. Perfect 5/9 signal!!!
I was given various pieces of advice including about the local nets and events throughout the week and frequencies (Thanks Alison!!)
The important ones to remember are:
So my next steps now are to re-program the radio and have a browse through the settings and of course join in the nets regularly.
If you are interested in getting into 4 meters then there is a wealth of knowledge within the club. Just come along to one of our meetings and ask! We will be happy to help!
There are also some great resources for the Simoco SRM9000 series of radios on the Simoco post linked here
Listen out for me on the weekly nets and I look forward to speaking to you!
73 de 2E0JPM
Folks,
Peter Blair, G3LTF, joins us on Thursday 9th March, 8pm at RADARC for a talk entitled “53 years of EME, then and now”. He will take a look at how it started and then a look at the scene today, in particular the technology developments. The concentration will be on the bands above 144MHz.
Prepare to be amazed at the possibilities and see how you might get started yourself!
Venue: Woodford Park Leisure Centre, Woodley, RG5 4LY as usual.
Refreshments will be provided as usual.
73
John
G4RDC
Folks,
Next RADARC meeting is Thursday, 23rd February at Woodford Park, Woodley, 8pm as usual.
Satellite operating is easier than you think! Tim Kirby G4VXE (of Practical Wireless fame – need I say more) explains how to get started on the amateur satellites as simply as possible. Hopefully afterwards, you’ll want to give it a go!
In the words of the great G3NGX “Get to your seat by 8.00. Pin back your ears at 8.10. Digest what you have heard at 9.30 and wash it down with a cup of RADARC coffee. Consider how this could change your life for the better.”
Looking forward to seeing you all.
Visitors welcome!
73
John
G4RDC
As of Friday 3rd February, a new GB3RD was put on air. It uses a similar type of base station but has new logic. The Repeater is now CTCSS only access so you will need to set an encode tone of 118.8Hz on your transceiver. The ident. is now by voice and occurs every 15 minutes.
The repeater is located on a farm and there are many potential sources of interference. To minimise these we have had a 3dB attenuator located in the antenna feeder. This has now been removed so the repeater should be 3dB (which isn’t much) stronger and also receive should benefit by the same amount. The implementation of full CTCSS should minimise potential interference.
Chris,
G4CCC. o/b/o Thames Valley Repeater Group.
Sunday 12th February 2017
HARWELL AMATEUR RADIO SOCIETY are holding a Radio and Electronics Rally at Didcot Leisure Centre, Mereland Road, Didcot, OX11 8AY from 10.00am-3.00pm. There will be radio and electronics trade stalls, a Radio Society of Great Britain bookstall, information on local courses for those who would like to become a Radio Amateur and an Amateur Radio Demonstration Station. Refreshments will be available all day. Entry £3.00 (children under 12 free). Details from Ann G8NVI on 01235 816379 or ann.stevens@btinternet.com
