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Archive for May, 2020

Wythall Radio Club members’ virtual visits

May 22, 2020 By: Chris G3YHF Category: Club, Fun, News, Training

Wythall Radio Club members spent their Tuesday evening on-line visiting each others’ radio ‘shacks’.

Using Zoom, 6 members provided guided tours of their amateur radio stations and antennas to a wider groups of about 15 members.  

An added high point was a visit to the fridge that Kev 2E0NCO keeps stocked next to his operating position!

The virtual tours were a big boost to those members still in lock-down. 

One member commented afterwards: “Last night was a lot of fun and a big pick me up for those of us imprisoned in our own home.” 

It showed the value of the Club taking part in the RSGB’s ‘get on the air to care’ initiative.

NEW Foundation licence course with on-line study and home exams!

May 18, 2020 By: Chris G3YHF Category: Club

COVID19 results in On-line Foundation course, with remotely invigilated on-line examination and no Practical Assessment Sessions

Because our Foundation courses, although on-line, require a compulsory Practical Assessments session at the club and an invigilated examination at an approved centre, we have had to suspend our usual training because of the COVD19 lockdown regulations.

However the Radio Society of Great Britain (RSGB) who regulate our training and examinations have decided that, for the duration of the lockdown, Foundation level candidates no longer have to complete the Practical Assessments.

Furthermore they have devised an on-line examinations system with remote invigilation which enables the candidate to take the exam in their own home. This overcomes the lockdown rules on association and distancing as we will have no need to meet with you whilst the lockdown rules are in force.

Therefore Wythall Radio Club have decided to run an on line Foundation course starting in early June and completing at the end of July for candidates who can take the examination on line sometime in August. There is no charge for the course but there will be a limit to how many candidates we can accommodate.

The Foundation course is delivered via a virtual learning experience (VLE) software named EDMODO which is free to use and has gained world-wide acceptance as a safe and easy way for tutors to connect with their students at home via the internet. Basically you sign up for the course and you get notifications via e mail that the course material and quizzes are available for you to download.

This will take place over a 7 week period with two lessons per week in the comfort of your own home and in a time of your choosing. We will deliver all the course material you need to complete the course but you will have to purchase the RSGB book “The Foundation Licence Manual” from the RSGB shop https://www.rsgbshop.org/acatalog/Online_Catalogue_Training_19.html

You will also have to book and pay for your remotely invigilated examination (£27.50) direct with the RSGB but we will advise on how to do this when you register to do the course.

So, if you or someone you know wants to take this unexpected opportunity then contact Chris G0EYO our training co-ordinator on [email protected] as soon as possible as there is not much time before the course commences.

Chris Pettitt G0EYO

How to operate 160 – 10M from a small garden

May 16, 2020 By: Chris G3YHF Category: Club, Fun, News, Training

Don’t let a small garden stop you from getting on HF – including 160M! – reports Wythall Radio Club member Chris G0EYO.

End Fed (or long wire) antennas are the most simple antennas an amateur can make for the HF bands. However their simplicity does come with serious compromises when used as a multi-band antenna.

The physical length as measured in wavelengths of the transmitting frequency can result in very high or very low complex impedances at the fed end of the wire, so they need a very good antenna matching unit (AMU) to enable a good match to the transceiver and to deal with the high voltages or current that may exist,

The high currents or voltages at the end of the wire can also result in serious RFI problems for the amateur which are hard to control. This is because a quarter-wavelength in from the far end of an end fed antenna, the current is at maximum and the voltage is at minimum. At a half-wavelength the reverse occurs and so on.

So for a given length of wire and depending upon the band being used a wide range of complex impedances and currents and voltages may appear at the transmitter end of the wire. This is sometimes more than the AMU can handle, both in terms of impedance matching and voltages.

The end fed wire antenna produces quite complex radiation multi-lobe patterns unlike the simple “figure of eight” radiation pattern produced by a dipole. With multi-lobes come deep nulls in certain directions (diagram thanks to VK6YSF).

They also need a counterpoise or earth return to work well and avoid RF getting back into the shack. Ideally these should be about a quarter-wavelength long for each band the antenna is required to be used on.

We can avoid some of these issues if we can avoid wire lengths which are multiples of a quarter-wavelength of the bands being used.

So how long should our end fed wire be? A great deal of work has been done by others on the ideal wire length which avoids very large end impedances for the bands of interest and these can be found courtesy of Google.

My garden allowed an end fed wire length of approximately 25m to be accommodated in an inverted “L” format between a 10ft pole mounted on the side of the garage and a 20ft pole mounted at the bottom of the garden.

Alan Chester G3CCB in his book “ HF Antennas for Everyone” (RSGB) came up with a useful graphic which showed “practical” lengths for end fed wires. This allows you to pick a length and see which bands are will give you a matchable end impedance.

I wanted to work on all bands from 160m to 10m but ideally 80m, 40, 20m 15m and 10m. Alan’s calculations showed that a wire length of 18.5m would give an workable end impedance on 80m, 30m, 20m, 17m, 15m and 10m with possibly a little more troublesome end impedance on 160m, 40m, and 12m.

To avoid bringing high voltages and currents into the shack the AMU should be mounted outside and the signal fed into the shack via 50 ohms coax. Fortunately I had an SGC 230 Auto AMU that I had installed at my previous house in Hollywood.

The SGC 230 AMU is designed to operate with wire antennas and is configured as an “L” or “Pi” type network controlled by a microprocessor. The initial tuning takes several seconds to determine the transmit frequency and then select the necessary coils and capacitance to match the complex impedance of end fed wire to 50 ohms. These settings are stored in a non-volatile memory so the subsequent retuning of the same antenna on the same frequency only takes a fraction of a second.

The tuner has a ceramic insulated antenna terminal which looks as if it would tolerate quite a few volts, and a threaded nut for a earth counterpoise. It has a flying lead from the AMU with a 50 ohm coax and PL259 connector for the transceiver together with a 5 core cable for +12V DC, earth and “Lock Tune” control line and “Remote Tuner” indicator line.

On my installation I have a small plastic box next to the AMU which is a through line for the coax cable and a terminal block for the DC and control lines.  A 25m length of RG213 goes from the interconnecting box back to the shack in a bedroom at the front of the bungalow. Similarly a CAT5 cable is used to feed the DC and control lines back to a remote indicator and switch box at the operating position. This tells me when the SG230 has achieved a satisfactory match and locked on (and which can be confirmed by the SWR meter).

The SGC230 AMU is in a weather proof plastic box and is mounted under the eaves of my garage. A very short earth counterpoise is connected to the AMU earth terminal using copper braid and fixed to a 1 m earth rod driven into the ground. Overall the earth counterpoise is about 5m long and should probably be longer or with multiple earth rods. Chris G3YHF has suggested I do this modification to see if the efficiency improves. The antenna wire itself is Kevlar strengthened wire which is very strong but also very thin.

The pictures show the installation. I should say at this point that the inspiration to put in this antenna came entirely from Roger M0GWM who in 2019 said it was about time I put up some antennas having lived here for 3 years. Together we came up with the idea of using a long wire. Roger also did all of the installation work including running the coax and control cables around the bungalow just under the eaves.

Not long after the installation was completed, and always being a data mode fan, I got Ian M0LQY to set up FT8 on my computer and transceiver which is controlled by an old version of Ham Radio Deluxe. I limit the power to 30W (effectively carrier power – and probably equivalent to 100W PEP for SSB) and have been very pleased with the results.

Bands 160m, 40m, 20m, 17m 15m and 10m are rock solid. 30m suffers from RFI which upsets the wired mouse on the main PC in the shack and 30m seems to be constantly trying to find a good match. SWR’s achieved on these bands are between 1.15:1 and 1.35:1 which I am very happy with.

Strangely enough I never tried top band on any mode  until Chris G3YHF encouraged me to do so on FT8. I found it fun and challenging so made it my Wythall Radio Club DXCC challenge for 2020 (55 countries on 160M at time of writing). Chris has a similar set up with slightly longer wire length and bigger earth counterpoise. Analysis of PSK Reporter reports shows he just has the edge on me when it comes to performance, so don’t let a small garden stop you working 160M – 10M!

Take the Foundation exam in your own home

May 12, 2020 By: Chris G3YHF Category: Club

You can now take the Foundation exam for an amateur radio licence in your own home.

The RSGB (Radio Society of Great Britain) is now offering remote invigilation in people’s own home for online Foundation examinations.  And the practical assessments have also been suspended.

Combined with on-line study, this means you can work towards an amateur radio licence in the safety of your own home.

These changes support the RSGB’s Get on the Air to Care campaign, as recently featured on the BBC.  It encourages the 75,000 radio amateurs across the UK—as part of the 3,000,000 worldwide—to use their radio licences to chat and support each other across the airwaves.

You can read further information here

If you would like assistance or advice on applying for a remotely invigilated Foundation examination, our Training Coordinator Chris G0EYO would be happy for you to contact him [email protected] 

From the “Orchard” Workbench 2: VGC-VR-N7500 VHF/UHF FM Transceiver

May 08, 2020 By: Chris G3YHF Category: Club, Fun, News, Training

The VGC-VR-N7500 VHF/UHF FM Transceiver is the new kid on the block.

I was asked for help from a neighbour who had bought this and could not get satisfactory operation via Bluetooth to his iphone. Mindful of social distancing, he left the package on our doorstep for me to retrieve!

Unpacking it revealed the transceiver itself, heavier than expected and very solidly built, measuring 6” wide by 51/2 deep max (including the external mounted fan), a decent looking wired fist mic, mounting bracket, power lead (12v to 13.8v) and a PTT button to attach to gear lever/handlebars etc. and a Bluetooth fist mic. It seems some of the latter are available as cost extras but were included.

Being mindful that it was borrowed I did not wish to programme it beyond basic simplex or repeater use, nor set up the APRS or network capability.

On the bench, it was a matter of moments to connect the antenna (SO239),the fist mic via the now almost universal network cable type connection and the power. The rig was fused on both +ve and negative leads.

Downloading the Android app via Google Play Store and installing it took a few moments.

Enabling the app and Bluetooth on a Samsung Android phone (other makes are available), the rig and phone paired and the application started showing my GPS location.

Swiping the page brought up the programming screen and it took just a few moments to put in both 145.225 and GB3WL together with split and CTCSS as appropriate. No messing with usb leads, downloading drivers, finding a suitable programming app (or buying one) and reading/writing to the radio, this is where this radio shines. So intuitive, so easy and you can be up and running in moments. If going mobile (this in truth is the market sector targeted) the unit can sit in the boot and just operate via the Bluetooth speaker mic or indeed the Android phone.

On FM, it is rated at 50watts VHF and 40 watts UHF and those power levels were achieved feeding my “white stick”

Google is your friend the full specs and videos are easily found.

Works really well and although the price is around £190,this being twice the cost of say a Anytone AT778UV, its added capabilities may tempt folk.

Being SDR it is firmware upgradeable (by Bluetooth) which may well bring in more features and/or bug fixes as the product matures.

A 30 page manual is available https://www.moonraker.eu/downloads/dl/file/id/309/product/9250/vr_n7500_manual_v3_1.pdf

The Manufacturers website has more detail at http://www.vgc.net.cn/product/54-en.html

Please excuse the extraneous “QRM” on my desk- the unit to the left behind the rig is my MMDVM running YSF to my Yaesu FT2D.

This unit was on very short term evaluation so the photos were taken in haste!

Our Club newsletter archive hosts hundreds of Members’ articles covering all aspects of Amateur Radio.

Take a look using the link on our website and click here for an up-to-date index of Newsletter articles

73

Ian M0IDR

 

 

 

 

 

Lockdown? Wythall Radio Club still busy!

May 06, 2020 By: Chris G3YHF Category: Club, Fun, News

Wythall Radio Club has moved in to ‘virtual’ mode during lockdown!

Members keep in touch ‘on the air’ – on our Club 2M channel and via our GB3WL 70cm repeater.   

The Club’s Easter Contest was very popular, with over 40 members participating.  And the results were shared via Zoom.

We are also using Zoom so that members can give talks and chat about radio activities – last night we had a talk on ‘getting on the air with RTTY’ (radio teletype) with around 20 members participating. 

This is all part of the way radio amateurs are connecting people during lockdown, as the BBC reported yesterday.  

Club members have also been working on creative projects at home. 

Allen 2E0VVG comments:  ‘Last week i turned an old laptop mouse into a morse key. 

Yesterday I decided to build a frame for my 817, LDG tuner and battery for when I can finally get back out on the hills (see photo above). 

And as I’m seriously restricted on where I can put my shack, I build a shelf to go above the unit out of left-over copper pipe fittings and an off-cut of wood.’

Meanwhile Kev 2E0NCO decided to rebuild his shack! (photo right) 

Maybe woodworking and DIY should be part of the Licence exams?

 

 

John G4OJL SK Remembered

May 04, 2020 By: Chris G3YHF Category: Club

Long-time Wythall Radio Club member John Bevan G4OJL recently became a silent key.
 
John joined the club in 2012 after a chance meeting with David G0ICJ. His initial interest was to join in with the ongoing morse class.
 
Although John was always associated with contacts on the key, he’d told me that after he’d passed the compulsory morse test in the 1980s he had not used it on air and didn’t like the mode. Indeed for a while he gave up the hobby completely and moved onto other pursuits.  Thanks to Chris G0EYO finding John’s details in an old callbook, John was able to get his original G4OJL callsign reissued.
 
John continued with the morse class, and by his own admission found it quite tough going and requiring lots of practice at home and at the club. He said that one Friday night at the club shack with Phil 2E0WTH and others, he heard Barry M0DGQ calling CQ on 80 metres without any station replying to him, so he very cautiously replied. This was his very first ever CW contact. 
 
After that John went from strength to strength, and was soon very comfortable on the key. His morse progression resulted in him being the second recipient of the Lew Williams Shield in 2013 (see photo, being presented by Lee G0MTN).
 
After that, despite being one of our more senior members in age, John continued to help out with the morse class, assisting with practical assessments with our training team.  He was an active participant in Club events, including Plug and Play (photo left, with Chris G7DDN) bringing some interesting antennas to try, at field days and other operating events, the Fun Run, and the Hamfest.
 
Club members recall him always being willing to answer a CW CQ, and being a dab hand at the ‘squeeze’ technique on a paddle key.
 
He entered almost all of the club contests, often sticking to CW only, but was also to be often found on FM for a local natter.  He also embraced DSTAR and recorded his activity on the Club’s ‘check-in’ website.
 
I’m glad that as a club we were able to help rekindle his interest in the hobby and facilitated several friendships with like minded people who enjoyed the same parts of the hobby as he did (photo left, with Les G0HOR and Alf G1MJO). 
 
You’ll be missed John – rest in peace. 
 
Lee G0MTN

Dots and dashes during May

May 03, 2020 By: Chris G3YHF Category: Club, Fun, News, Training

It’s May! And Morse Code appreciation month at Wythall Radio Club.

Everyone knows some Morse Code:  ‘ …  – – –  … ‘ = SOS!

At Wythall Radio Club during May we celebrate the skill of communicating by Morse Code in honour of Lew Williams, who was an expert at Morse and former Club President.

So Club members will be having fun by making contacts with other amateur radio operators using their Morse keys – which come in all shapes and sizes!

Many are ‘side-swiper’ keys, in which one paddle send dots and the other sends dashes.

Side-swipers are often used instead of the traditional ‘pump’ key, with its up and down action, because they reduce the amount of wrist action and operator tiredness.

However, pump keys are much better for learning Morse and for slower contacts. 

Here’s a short explanation for younger readers of how Morse Code was invented (you can skip the advert at start!).