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Est. 1938 Club Call G4HRS

The Journal of

Horsham Amateur Radio Club

February 2020

Sponsored by: Affiliated to:

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ContentsIn this issue

3. Notes from the Editor OS end and yearly subs

4. Time to show Members describe their interests

11. Don’t get lost The fox needs you to take bearings

12. Invitation Time for a spring clean

13. Radio comes to TV Michael finds some Kilowatts and we visit the Solent

15. Diary of events Full listings for the month

Cover photo: Floods!

Published by Horsham Amateur Radio ClubHARCNEWS is produced at home by G4JHI

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By the time that you read this Microsoft will have ended support for Windows 7 versions. Since October I started the upgrade process including the purchase of a new desktop machine which is what I am using to produces this newsletter. During the Christmas break I completed the upgrade of all my computers to Windows 10.

Editorial

Although not mandatory, by associating the operating system with a Microsoft Account one can get the option to sign into Windows 10 with just a pin number which I use and will make life easier. This new purchase has a Solid State hard drive for the OS and a separate mechanical drive for all the data which is a good idea and all backed up to the cloud. If you haven’t already paid your club subscription for 2020 below is a reminder and can be paid to the Treasurer by various methods.

David G4JHI

Copy deadline for emailed items for March edition 20th February - For written items the deadline is 12th February.

For items sent by email please send to this address:

harc.news@g4jhi.co.uk

2020 Subscriptions

Subscriptions are now due for the 2020 Club membership.

Please forward £15 to the Treasurer Paul G4TMC.Payment can be by cash, cheque (payable to H.A.R.C.) or via electronic transfer.Anyone wishing to pay electronically should send an email:paul.g4tmc<at>@gmail.comYou will then receive by return the HARC bank details.

Postal address: Paul Barnett, 8 Parsonage Road, Horsham, RH12 4AR.

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We started the evening with a demonstration of the Club’s shiny new IC-7300 SDR HF transceiver by the hon Chair, G4LRP. A short vertical whip antenna was erected in the Guide Hall’s garden for this demo. The Icom has a useful-looking waterfall display and is very easy to use. It seems to be an excellent rig. The emporium chucked in a tiny AM/FM receiver freebie but no power supply or handle which are optional extras. An SD card can be used to store configuration information but it works really nicely as supplied with its default settings.

January 2020 Meeting

Bring Show Tell

IC7300

David 2E0NKC then demonstrated a Tecsun AN200 medium wave loop aerial. This device can either be plugged into a receiver via a cable or inductively coupled to a receiver’s internal ferrite rod aerial. Cost is a very reasonable £28. The loop has a diameter of approx 10 inches and has a tuning capacitor mounted in its base. Tuning is quite sharp.

This loop increases the sensitivity of the receiver and some of the stations heard are Grenada, the Windward Isles and Toronto CFRB. The only disadvantage is that it can also amplify signals for adjacent stations and that could swamp out the wanted DX signals.

Richard G4ANN was unable to bring the repeater he was working on but at least he brought along some photos of it. The GB3MH repeater failed so a re-build was in order but it is still work-in-progress. The repeater has two Motorola FM radios controlled by some logic and a Raspberry-Pi to facilitate echo-link access. There is currently a problem with stray RF that needs solving. GB7MH does all the digital modes.

Tescun AN-200 loop aerial

GB3MH repeater

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Phil G4UDU showed a battery pack suitable for portable operating. It uses ‘18650’ LiFePO4 cells, 4 of these give 13.96V at 1600mAh. Unlike LiPo batteries, these do not catch fire and are considerably safer. The only down-side is less capacity. They have built-in circuitry to prevent over-charging. Each cell costs about £3. Cheap programmable dc-dc converters can be obtained that convert 5-30V in to 7-30V out at up to 4A, and these can be conveniently used to charge the battery pack from a carbattery or solar panel. A screwdriver is used to program the dc-dc converter via a 10-turn pot.

DC-DC converters

Next came two car-related items from Robin G3OGP. A 12Ah battery pack that can be used to jump start a car as it can supply up to 200A. Robin expects that there could be a large capacitor to give the peak current. Two short thick leads can connect to the car battery. This pack also has a torch lamp and 5V USB outlet. This was £33. He then showed us his adjustable wire strippers that he was most impressed with.

Car battery booster plus wire stripping tool

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After the tea-break, the hon sec G3ZBU showed us some of his recent projects. The first was a capacitor meter designed for the RSGB’s Convention Contest Challenge. It uses a PIC’s built-in CTMU (Capacitance/Time Measurement Unit) which was designed for touch-pads where the pad can be behind a vandal-resistant plastic (Perspex) sheet. Surface-mount capacitors have no marking on them whatsoever, so the plan was to be able to clip a s/m capacitor across two Veroboard tracks and an LCD display shows the reading. There is a tiny bug in the software that needs looking at.Needless to say, it did not win...

Capacitor meter

The second RSGB project was a data modes interface for the Icom IC-706. Sadly it does not have VOX on its data audio input, so G3ZBU used a PIC to digitise incoming audio from a PC, and pull down the PTT line if the audio exceeds a level as set by a trimmer potentiometer. More modern Icoms allow for T/R switching on the CIV interface, so a CIV=controlled IC-7300 should be fine for PC-controlled data modes.

IC-706 data modes interface

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Next project was a LoRaWAN node. This receives LoRa signals on the 868MHz band and sends them to a server via the Raspberry Pi and WiFi dongle. Some high-altitude balloons now use 868MHz LoRa transmitters. These transmitters have a range of about 20km over land and are designed for ‘Internet of Things’ devices that send very short messages usually at regular intervals. One node can handle thousands of devices. As commercial use of the servers costs a fair bit, this development was abandoned.

868MHz LoRaWAN node plus two LoRa devices

Some vendors are happy to give away free kit for design contests. One such project was a Microchip AVR board which G3ZBU added two thermistors so that the temperature differential of a central-heating radiator could be optimised for efficiency. This was supplied free-of-charge! This board has a Wi-Fi module on board and sends temperature data to a server in Arizona. One can log into it and see graphs displaying recent data.

Microchip AVR Wi-Fi board plus mains relay

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The hon sec had problems with the fridge getting badly iced-up, and a replacement thermostat made no difference. The AVR project was up-cycled to switch the compressor off if the fridge’s temperature dropped below a pre-set level. One of the thermistors was poked up the drain hole, and a relay added to disconnect mains. This is not an ‘Elf’n Safety’-approved project!

Another set of free boards came from Cypress and these use Bluetooth Mesh. But programming these has to be done with high level programming, unlike Microchip PICs, so they are not working yet as it is beyond the hon sec’s tech level! These are ideal for in-house sensors as they are very low power. Typical applications are for controlling RGB LED lighting.

Cypress Bluetooth Mesh board with two temperature sensors attached

John G3WZT showed us an antenna ATU & control unit that he uses and took it apart to view the contents.

Aerial switching control box

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As usual, the Bring, Show and Tell evenings show that homebrew is alive and well!

G3ZBU

Aerial switching power supply Aerial switching relay unit

Aerial switching power feed Aerial switching PCB

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HARC 2m Fox Hunt

A reminder that the Club has a Fox Hunt in the diary for Sunday 16th February.

Details are as follows :-

Start :- Robin, G3OGP’s QTH

Garlands Farm, The Haven, Billingshurst, RH14 9BH. OS ref TQ082312.

Time :- First call at 10:00 and every 10 minutes thereafter until the last call at 12:00.

Frequency :- 144.725 MHz

Maps :- OS Landranger Nos. 186 (Aldershot & Guildford), 187 (Dorking and Reigate) and 197 (Chichester and the Downs).

Fox :- Andrew, M0GJH using G4HRS

I have found a good pub which does Sunday lunch and offers an excellent range of cask beers. I have provisionally booked for 12 but please confirm if you would like to eat and how many in your party.Email: m0gjh<at>btinternet.com

I look forward to seeing all on the 16th.

73 Andrew

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HARC SPRING JUNK SALE

Thursday March 5th 2020

2000 Hours start Doors open 1930 for viewing and arrival of items Free entry Food available The Guide Hall Denne Road Horsham RH12 1JF See you there!

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TV Addict

by David Miller G4JHI and David Ansell 2E0NKC

Great British Railway Journeys

On January 8th Michael Portillo’s Railway Journeys on BBC 2 were in Scotland. Michael visited the Westerglen transmitter station near Falkirk. The show featured the two masts and Michael in the transmitter hall where he was shown the long and Medium-wave transmitters. The station opened in 1933. Michael asked “what is this noise?” It was the cooling fans. The person showing Michael around said that there was still a future for analogue radio as one transmitter can cover a Large area whereas FM needed several transmitters and DAB even more.

Westerglen transmitter station

Note – Westerglen transmits Radio 4 on 198 kHz and BBC Radio Scotland on 810 kHz (audible at night in Horsham) and BBC Radio 5 on 909, Talk Sport on 1089 kHz, Absolute Radio on 1215 kHz.

Solo DinnerAt the end of 2018 this column took a look at Dinner for One very popular in Germany and some other countries. It came to my notice after that particular New Year that the Sky Arts channel now broadcasts the comedy. On New Years Eve just gone I actually watched the programme on that channel. Because it is on British television and the first couple of minutes are solely in Germany subtitles are provided. So now a complete scenario of the proceedings is known since I only understand a few words of German! Admittedly the broadcast was the black and white version but it was still as enjoyable as always!

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TX Factor

Episode 25 a post election special is now out and asks the question ‘Wot! No Internet?’. Also a look at some more new and innovative AR products from this year’s Hamfest, visit Southampton and Portsmouth on the UK’s south coast to see how two city councils, assisted by a group of dedicated amateurs, plan to maintain their communications infrastructure via radio links.

https://www.txfilms.co.uk/txfactor/

Zöe Johnson SWL from Weatherquest

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Diary

Feb 3rd, 80m SSB Club Championship 20:00 - 21:30

Feb 6th, Club Night: HARC - CARC Challenge

Feb 9th, Harwell Radio & Electronics Rally - Didcot Leisure Centre 10:00 - 15:00https://www.g3pia.net/radio-electronics-rally

Feb 12th, 80m Data Club Championship 20:00 - 21:30

Feb 16th, Sunday Morning Fox Hunt - Andrew M0GJH 10:00

Feb 13th, Social Evening: The Star - Rusperhttps://www.thestarinnrusper.co.uk

Feb 22nd-23rd, Guides Thinking Day on the Airhttps://www.guides-on-the-air.co.uk

Feb 27th, 80m CW Club Championship 20:00 - 21:30

Mar 2nd, 80m Data Club Championship

Mar 5th, Club Night: Junk Sale

For details on the above contests use this link and follow to the appropriate sectionhttps://rsgb.org/main/radio-sport

All above times are UTC

Committee/Club Meetings and Socials start at 20:00