Tag Archives: SVARS

Club Meeting 04-05-2017 – a talk by Gordon, G0EWN – “Lightwave communication”

This evenings meeting was the first meeting of the year with a guest speaker, Gordon Fiander, G0EWN, who spoke about his experimentation in communication by light.

The LED light source demonstrated by G0EWN
The LED light source demonstrated by G0EWN

Using a high powered LED light source Gordon and Barry (G8AGN) hold the UK distance records for communication over a path of 120+ kilometers.

G0EWN's LED transmitter
G0EWN’s LED transmitter

The main issues to overcome are light pollution and aiming accuracy, though the available bandwidth means many different modes can be used.

This was a fascinating evening, enjoyed by all members who attended. The committee would also like to note that Gordon requested that we donate his “expenses” for the evening to the Derbyshire Cave Rescue Organistation, which we happily did. More details can be found at https://derbyshirecro.org.uk/

Club Meeting 05-05-2016 – Cuba on CW

With nothing special planned the members met for a “noggin and natter night”, but this time we decided to open up the shack.


Tuning around 17m, chairman Ian, G7DWY found CO8LY on C.W. Eduardo in Santiago de Cuba. The only problem was no key!

We have two keys, but no-one got around to putting a plug on the keyer, and the Junkers straight key had the wrong plug. Plug found the Junkers was rewired and much to the amusement of all Ian called….

On the Third call, a QRZ. Repeat the call a couple of times and hey presto, CO8LY in the log (followed by a round of applause from the members!!!)

Come and see us one week – we are usually friendly….

Club Meeting 19-11-15 – DMR is GO!

This eveing, Michael, G1XCC brought a Motorola DMR repeater to demonstrate.
 Set up in literally five minutes, connected to a wifi router and a 4G mobile phone the repeater logged on to the network over the internet and instantly we had world wide coverage from a hand held radio!

 
Not at all bad from a UHF hand held – listening to a USA station talking to an Italian! 

The preffered antenna for site is a unity gain as the repeaters are internet linked and auto roam to the strongest signal, so it’s better to use low gain aerial with a good low take off angle.
  
Thank you, for the demonstration, Michael.

If you would like any further information on the “”Yorkshire FM & DMR repeater group (formely the five towns repeater group)” please visit their website .

Club Meeting August 20th 2015

Well the summer break from organised talks is nearly over, but this evenings meeting saw John, G3TSA bring a box full of assorted small switches for members to help themsleves to – Thank you John!

Later Trevor, G6XTZ brought out his Motorola DMR handheld and Michael, G1XCC brought his laptop to program it with the latest repeater and trunking frequencies.

  
Note that the pint of beer isnt always required for the programming operations, but it helps!!!

Club Meeting 19-03-2015

Well, another evening with no official agenda, but as usual there were a number of interesting items brought in for people to peruse, play with and generally explore.

John, G3TSA brought a box full of ex-equipment coils for people to take if they desired. A few bits and pieces went home with new owners…

He also brough a dead valve – an amperex 7092 which when it was operational would develop about 1.5kW output on the HF bands (post meeting note – John was obviously being conservative! – the 7092 is rated to 2.5kW at 50 Mhz!!!)- Not any more though.

David, G4IDR brought some screenshots of his latest 144Mhz EME conquest – working the falkland islands DXpedition using a single yagi and 400w. Well done!

Unfortunately, Dave suffers from RF issues from a local commercial mast, so Douglas, G4DZU and Ian, G7DWY brought him a selection of preamplifiers and filters to try to see if any have a marked effect.

Conversations around the table varied from DC connectors, HF valve and solid state amplifiers, homebrewing  RF bits and bobs.

Please come along to the next meeting 

Club Meeting 03-03-2015

Whilst there was no formal talk this evening, we had a wide array of interesting items brought in for people to look at and play with.

John Denby, G3TSA brought in a number of items, the first of which was a home made power meter that he made many years ago, but is still fully operational

Capable of measuring from milliwatts directly up to hundreds of watts using the directional coupler:

Next up from John were some ex-equipment 50v DC 750 w power supplies made by lucent technologies. There are ideal for the latest generation of LDMOS RF amplifiers using devices such as the BLF 278, or with a couple of supplies in parallel the larger device like the BLF578XR or MRF6PV1K25 which are capable of RF outputs into the kilowatts!

John also brought a rather beautifully made electronic barometer which is probably ex military, and still fully working

Michael, G1XCC brought a long a high quality optical gun sight, good for ranging items over a kilometer away. A number of members took a look, and conversation turned to the possibility of using it for sighting a light modulation project between local hill tops.

As always the conversation were many and varied. Please come along to the next meeting, which will be on thursday March 19th.

Club meeting report 19-02-2015

Although there was no formal agenda for this evenings meeting, several members brought things for others to see and try.

After the last meeting where we modified the club TS570 to cover the upper portion of the forty meter band, Stuart G0TAL asked if we could perform the same ‘surgery’ on his FT847. The modification required the removal of an 0402 surface mount resistor, which was done with a hot air soldering station.

Here, Stuart can be seen inspecting the rebuilt radio.

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After a conversation with Tony, M5AIB at the last meeting, Ian, G7DWY brought his ‘portable radio backpack’ which contains an Elecraft KX3, PX3 and a Hardrock 50 P.A.

It was set up on the clubs HF dipole and caught the imagination of Roy, G4YDI who spent an hour or so on 40m CW….

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David, G3PTU, brought along a home built power meter, based on a linear devices LTC log amp. Unfortunately, I forgot to take a photo – sorry David!

As per usual, there were lots of different conversations ongoing, from HF conditions, E.M.E., homebrew QRO P.A.’s, home brewed beer and caravans!

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Why not come and join us at the next meeting on March 5th?

Club meeting 05-02-2015

There was no planned “event” for this evening’s meeting, but we ended up with eight members and one non member visiting.

Ian, G7DWY brought along a hot air soldering station and decided to modify the club HF radio, a Kenwood TS570D so it covered the whole of 40m and 60m – something that we have been discussing for a while now. The process was simple enough – it took more time to strip the radio than it did to remove the resistor! The picture is of the radio after the resistor had been removed.

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David, G3PTU brought along an SWR / Power meter which he bought from a rally for next to nothing as ‘none working’ it turned out that the meter movement was faulty, but soon replaced and life was once more breathed into it!

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Trevor, G6XTZ brought along his new Motorola DMR handheld for people to play with and Tony, M5AIB brough his laptop and a couple of radios to program, but we ran out of time, so this may be carried over to the next meeting.

At the next meeting, if things go according to plan, Stuart, G0TAL will be bringing his FT847 to receive the same treatment as the clubs rig did this week and hopefully Tony will be bringing his programming equipment….. If you would like to come along to a meeting, drop a line to the secretary on just turn up.