wythall radio club

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.

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!

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

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?

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!).   

Wythall Radio Club members gathered on Zoom last night to hear the results of the annual Easter Contest.

Over 40 members participated in the contest, and highpoints were QSOs with some of our more distant members in Scotland, Torquay and Derby. 

Besides using 2 meter FM and our 70 cm repeater GB3WL, there were qsos on the 160, 80, 40, 10 and 6 meters bands, using SSB, CW (Morse Code) and digital voice, as well as on our Zello channel.

In the 2m/70cm FM section, Maz M6NKO won the award for the highest placed Foundation licencee. 

The overall winner was Kev 2E0NCO, who will be awarded the Colin Baker G6ZDQ Easter Contest VHF/UHF Shield, in memory of our former Club member.  Over the 5 days of the contest he achieved 124 QSOs with 37 different Club members  giving a total score of 3071 points!

Miles 2E0YZW retained his second place position from last year with 1984 points, and Roy G0HDF was third with 1250 points.

There was very close competition for the top places in the all bands/all modes section.  David G7IBO came first with 124 QSOs with 43 Club members over the five days, and a total score of 3655 points.  He will be awarded the David Dawkes G0ICJ Easter Contest all bands/mode section Shield, in memory of our former Club member.

Close behind was Stuart M0NYP who had more QSOs – 134 – but fewer multipliers giving a total score of 3560.  Ian M0LQY was third with 2664 points.

Tim M6OTN, based in Worcester, won the award for the highest placed Foundation licencee in this all mode/band section. 

Club members like Sylvia M3SSP had support from a junior operator, others (G0MTN) had their rig in a convenient cupboard, and Allen 2E0VVG had his on a bike!   

The G6ZDQ and G0ICJ shields will be presented when Club members are once again able to meet again face-to-face.

Our usual prizes of Easter eggs will also be awarded when the Easter chicks start laying again!

As usual, Stuart M0NYP captured the five days of radio fun in a cartoon!

Ian M0IDR – a Wythall Radio Club member – reports on his build of this small low power transceiver.  This is the first in a series of reviews. His home is in a former orchard area, hence the title of these posts!

The QCX is a 5watt CW only transceiver with a very compact footprint which is available ready built or in kit form. Unfortunately the rather good aluminium case was discontinued in January 2019 and my purchase was a kit with case just as QRP Labs announced the change. The case can be bought elsewhere and details are on the QRP Labs website.

The kit and case shipped from America without any Customs charges, although it took some 5 weeks to arrive. Very well packed indeed with all components bagged by type.

Not for the faint hearted, I suggest, as assembly involved a fair bit of tricky intricate coil winding.

The assembly instructions are downloaded from the website and run to over 140 pages of very clear detailed instruction.

Having a fine tipped temperature controlled soldering iron made for perfect soldering first time around as removal of any multilegged component would prove very difficult. A desoldering station was on standby just in case.

The multi-winding coil was by far the most difficult to assemble but inductance measurements proved each winding before fixing into position (photo left).

Assembly proceeded in strict order of instruction and the completed board was mounted within the case (photo right).

Assembly complete – the unit on test (photo below)!

Since building this, I have purchased a second user GPS module – QLG1 – which can be added to effectively use the rig as a WSPR beacon.

This module is only available in kit form and interfaces to the QCX via a 4 core umbilical cord.

For the moment, I am pleased that the QCX assembly was trouble free and look forward to interfacing to the GPS module when time permits.

Here’s an example of the true amateur radio spirit!!

Back in 2011, Gregg K6GDP – from Salem, Oregon USA – had a contact with the English station M7A.  Gregg discovered that he needed confirmation of the contact to complete his entry for an award. 

M7A is a special callsign used for contests, but the current holder only acquired the call in 2017.  He told Gregg he thought that the call was used by Wythall Radio Club members.

Gregg (seen with a Chinook salmon!) approached our Club, but it wasn’t a callsign we had used. 

Undaunted, Club member Lee G0MTN beavered away though the on-line records of the CQWW SSB 2011 contest.  He discovered that M7A had been used by the Lithuanian radio amateur Jay LY4A, while based in England. 

Having passed the info to Gregg, Lee received the following reply:

“I’m truly grateful for all the effort expended on my behalf.

I’ve sent off a note to LY4Y to see if he can check his log.  If he can, that would be great, but even if he can’t I am gratified to have ‘met’ all of you folks who have been so genuinely helpful in my quest.  

When propagation improves I hope to have the opportunity to meet you each on the air.

Be well and 73,  Gregg”

Glad to be of assistance, Gregg!

Oh, and that Chinook salmon weighs in at almost 40lbs and took Gregg 30 minutes to land into his boat on the Siletz River in the Pacific north-west coast. 

Happy fishing on the air waves and in the water!

Wythall Radio Club members participated in this year’s World Amateur Radio Day (WARD) by contacting stations around the world.

Saudi Arabia, Canada, Georgia (photo left), Romania, Israel and Kuwait were amongst the countries with whom Wythall club members had two-way conversations on the short wave bands.

Contacts included stations with special ‘WARD’ callsigns.

John 2E0XET worked HZ1WARD (Saudi Arabia) using Morse code on the 20 meter band, Chris G0EYO contacted AM1WARD (Spain) using digital mode FT8 on 160 meters, and Chris G3YHF talked with 5P0WARD (Denmark) on 40 meters.

Amateur Radio experimenters were the first to discover that the short wave spectrum — far from being a wasteland — could support worldwide propagation. 

Today, 100 years later, Amateur Radio is more popular than ever, with more than 3,000,000 licensed operators worldwide!

Amateur radio community has proved vital in recent emergencies – when mobile phone masts and telephone lines are out of action, radio amateurs often provide the only means of communication with the outside world.  

World Amateur Radio Day celebrates the fun of amateur radio and its scientific and humanitarian contribution.

If you are tuning around in the next few days on the 2 metre band or on GB3WL in the Birmingham area (or even further afield) and hear some stations exchanging numbers, you just might have stumbled upon the Wythall Radio Club Easter Contest. 

Just as at Christmas, we hold an event to get our members on air and working each other.

Points are given for each member worked and each discrete member worked across the period also counts as a multiplying factor (or multiplier) to attain a final score.

It sounds complicated but we have a clever Excel spreadsheet which keeps score for us!

The best 3 days of the 5 days of Easter are adjudicated and the top 3 winners in each category get Easter Eggs as prizes. With 6 chocolate prizes, it’s a short but highly contested event.

Watch this space for the results!