Making Waves – New QTH and new Challenges

IMG_20180401_094736

Recently we moved from Grantham – IO92QV – to Kirkby in Ashfield – IO93IC.  The Grantham QTH was OK for HF but useless for VHF and above as it was in a dip, totally surrounded by high buildings and 200ft hills containing iron ore.  The new QTH however is 154m above sea level offering great prospects for VHF and UHF – but how to take advantage of them?

The first challenge we faced was the weather.  On the day we moved (27/02/2018) we were hit by the worst snow storm in 20 years which closed off roads and communities across the UK. To add to our problems the heating didn’t work so with sub zero temperatures and no hot water there were other priorities before thinking antennas and such.  Getting an emergency plumber out in those conditions was not easy and it did take two days to do so.

However, I did eventually manage to get up a 14MHz EFHW as a temporary antenna for HF and a collinear for VHF.  I also bought a new 2m radio – the Yaesu FTM3200D so I could see what the digital mode (C4FM / Fusion) was about.  This proved to be quite interesting, providing a very clean signal, but sorely underused.  With standard FM I can now access GB3LM, GB3NF and GB3CF – Lincoln, Nottingham and Leicester repeaters on 2m.

IMG_20180420_095600 The FT-480R 

I also use a Yaesu FT-480R for 2m.  This provides 10W output on FM and CW and 30W PEP on SSB.  For SSB and CW a vertically polarised antenna is not much use so I needed to raise my 10 element diamond Yagi form the garden to a good height .

IMG_20180405_150406_676 UHF and VHF Yagi antennas in garden 

Obviously, not having a suitable ladder for the task I called on the services of a local antenna installer who came round and duly fitted it up on T and k brackets for me.

IMG_20180409_170222_766 Above the roof now… 

With the antenna in this position I have managed to work into Scunthorpe (North East) and Wales (South West) on 2m SSB. I also have a 13 element Yagi (DL6WU) for 23cm but that has yet to go up.

For HF I am using an HW-40HP OCFD at 8m AGL – this is about 1.5m below my 2m/70cm collinear.  When (if) the rain stops I am also going to set up a long wire for 80m.  The garden is a little over 20m in length so this should be quite easy.

IMG_-yyscmf The Collinear with the HW-40HP below it.

Making Waves – Double Trouble – a simple diplexer.

There are often times when a simple diplexer is required – perhaps you are wanting to try your hand at satellite communications or perhaps you are using separate antennas on a mobile dual band radio. Whatever you are planning you may find that commercial diplexers are costly so why not build one for yourself? Above is the schematic for a simple diplexer. The connectors, PL1, PL2 and PL3 can be replaced with BNC, N-type or whichever socket you prefer for coax connection. PL1 is for the coax run to your transceiver, PL2 for 70cm and PL3 for 2m. C1 and C2 are both 4.7pF and C3 is 10pF. L1 is 0.05uH or 1.5 turns of copper wire (1.0mm diameter) wound on a pencil, L2 and L3 are both 0.07uH or 3 turns of copper wire (1.0mm) wound on a pencil.

Use a small piece of PCB material / copper clad board as the earth an solder the components together – not the prettiest thing but you could put it into a small box.

For satellites you will need two small Yagis, one for 2m and one for 70cm at right angles to each other. on the same boom for handheld work and fed with a short piece of coax (50ohm) from the relevant output on the diplexer and then a short run of coax back to your transceiver. The capacitor type is optional but remember, the higher voltage rating on the capacitor, the higher power throughput you can expect however, for satellites you shouldn’t need more than 10W other wise you may cause unnecessary interference to other users or simply overload the satellite’s transponder.

For mobile setups with two antennas for a dual band radio, a short length of coax from the radio to the diplexer and then sufficient coax to each of the antennas from the correct port / connector. No external power source is required for the duplexer as it simply works as a high pass filter allowing the 70cm (and higher) signal through and a low pass filter allowing the 2m (and lower) signal through.

Making Waves… What of 2020

February 4, 2021 Leave a comment

Well, 2020 certainly hit us hard. Last time I wrote on here regarding my radio was when I won an IC-746 in an eBay auction. I was actually in the hospital with my wife when that auction ended as she was being treated for a perforated eardrum – funny how we remember things like that. Not long after receiving the IC-746 Covid-19 struck and we were placed into national lockdown. With both my wife and myself having health issues we have continued to isolate as best we can with minimal trips for shopping – even when the lockdown was lifted to a tier level temporarily.

Anyhow, the IC-746 was supposed to be a second radio whilst my FTdx1200 got repaired but it evolved into a second main radio in the shack. I bought a new sturdy bench to sit it on and treated myself to an Acom A1010 linear amplifier which arrived on 27/05/2020. This meant I now had two independent HF sets with independent amps running into independent antennas. Whilst everyone was saying that the bands were flat and it was pointless turning on the radio I worked BG4NMT in Shandong, China using 400W CW on 20m on 29/05/2020.

fig.1 The IC-746 and A1010 line up

I had also bought myself a new rotator – a Yaesu G-450C to replace the one that had been destroyed beyond repair during the storms late in 2019 and early in 2020. I bought a sturdy 2inch scaffold pole and some decent guys to support it and mounted it up with the 10 element Diamond Yagi above the rotator. I actually had to replace some of the elements on this as the previous rotator had eventually sheared in half and the stub mast had fallen with the VHF and UHF arrays damaging both. Some of the existing elements are still a little bent but I shall get round to replacing them later as it still functions.

At the end of May we were treated to an amazing tropho opening on the 2m VHF band and I managed an all time best DX with CT1DIZ (Portugal) on 144Mhz SSB. This is a distance of 1066.3 miles or 1716.0km from here in central UK. Of course, during the lockdown, more amateurs have turned on their radios to beat the loneliness and there has been somewhat more activity on 2m SSB whilst people keep in touch with friends that they are not able to see with the restrictions. This means I have been able to work many more stations across the UK and Ireland that I probably wouldn’t have heard under normal times.

Of course, time has still been a constraint for me when it comes to operating on the radio as I have continued working throughout the period that we have had the Covid-19 pandemic and subsequent lockdowns. It has meant that I have had to change distribution systems somewhat and no longer have people collecting stuff but I have managed to acquire some new commercial deals that have enabled me to afford the new items spoken of above. We are now in February 2021 and, hopefully nearing the end of this terrible pandemic but who knows. Hopefully we will all soon be able to get back to some sort of normality and see our families again.

Anyway, until next time……….

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Making Waves – CQWW CW 2020

November 30, 2020 Leave a comment

We’ve just had the weekend I look forward to each year as a radio amateur – CQWW CW contest weekend. For those who don’t know this is a 48hour contest making contacts all over the world using CW (Morse Code). There are many large contest groups who may use large antenna arrays and high power (up to 1.5kW) but I used my Yaesu FTdx1200 transceiver (max 100W) and an HW-40HP off centre fed dipole. The HW-40HP is cut to resonance on the 40m band as a full size dipole and then, as it is off centre fed via a 4:1 BALUN, also works on the harmonic bands.

The HW-40HP

Apart from being a contest, to me it is a chance to test the efficiency of the equipment I use from my own Ham radio station. Each year I aim to better my score from the previous year and this year I managed 271 contacts in 76 countries and 26 zones giving a total score of 35,598. My score last year was 11,760 so I certainly beat that one. So what have I changed to make my score better? Well, this year I have raised a new 8m mast at the bottom of the garden and the antenna is connected to this as an asymmetrical inverted Vee. This places the antenna well away from buildings and, as the location is 154m above sea level, plus the 8m above ground level gives a pretty clear view in all directions. I also tried it out on different bands this year.

The FTdx1200

I started out at 07:19UTC on Saturday 28th November 2020 on the 40m (7Mhz) band as it was still pre-dawn and I didn’t expect the higher bands to be open yet. I stayed on here until 08:37 when I switched to the 20m (14Mhz) band. My that was busy and whilst on there I was pleased to work as far as Peru (OA5) and the US Virgin Islands (KP2) which were both new ones for me. At 13:23 I switched to the 15m (21Mhz) band where I worked station after station from the USA and Canada. Seems that new solar cycle is starting to take effect when the higher HF bands come into play. I stayed on here until 14:36 before switching back to 20m for a short blast and then to 40m at 15:07 when the light began to fade. I stayed on 40m until 17:04 when I went for tea and stopped for the day.

Myself in the contest

The following morning I started up at 07:06 on 40m again and after a brief spell decided to attempt to use my 40m antenna on 80m (3.5Mhz) from 07:17. I pressed the “Tune” button on my transceiver – the FTdx1200 – and the internal ATU matched it with no difficulty. After all, 80m is very much a dark band as it tends to fade during daylight hours. I managed to work several UK stations and a few near continental stations (including Aland Island (OH0). I returned to 40m at 07:40 and worked a few more stations until I started just receiving the same stations over and over (duplicates not allowed) so switched to 20m at 08:15I continuing until 12:36 when I stopped and packed up altogether.

Making Waves – A DIY HF Antenna for the smallest spaces

July 16, 2020 4 comments

Is your garden the size of a postage stamp? Or maybe you live in a flat/apartment with just a balcony, then this could be the antenna for you to get on the air using HF frequencies. We all know that an HF dipole for 40m (7MHz) is going to be 20m (66ft) in length and not everyone has the available space to fit one in (hell, a 1/4 wave vertical is going to be 10m (33ft) long and may require planning from your local authority. So how about a vertical antenna that is only 1.7m in length and covers all HF amateur radio frequencies from 7MHz to 28MHz via your ATU? Impossible I hear you say, not at all – read on to see how it is done….

What will you need? Not much really, you will need a length of plastic pipe, 1.70m long, 41mm in diameter – this is sold in the local hardware stores as 40mm waste pipe but be careful, 40mm is the inside diameter and it is available in either 41mm or 43mm outside diameter – 13.6m of 1.5mm insulated copper wire, some 20mm long cable ties (200 * 3.6) and a 4:1 UNUN (see later for instructions).

Effectively, take One end of your wire and secure it to one end of the 1.7m pipe using one of the cable ties. Wind on 67 turns of the wire over a length of 220mm and secure with a cable tie (insulating tape can also be used). Now drop the wire vertically for a length of 360mm and secure again. Wind on 22 turns (in the same direction as previously) over a length of 70mm and secure again. Then wind three turns, wide spaced over 820mm (and secure again leaving the end free. This end then needs attaching to your 4:1 UNUN.

For the 4:1 UNUN you can either build your own by following the image below:

Or buy one ready made (Magituner A) from www.m0cvoantennas.com .

Leave a short amount of space at the bottom of the pipe to fix either a bracket (if you are going to pole mount it) or use cable ties to fix it to railings on your balcony, etc. You will need to attach an earth wire to the second peg/machine screw. This only needs to be short – maybe 4 or five foot but does help with the matching. Attach coax to the SO239 socket using a PL259 plug and run back to your radio via an ATU (the internal one (if fitted) may be able to cope with this) tune up and away you go.

Making Waves – Reducing Power

From time to time we all need to reduce the output from our transmitter – maybe it’s in order to use sensitive equipment such as a Spectrum Analyser or oscilloscope to test the output from a transmitter we are building or from an existing transmitter that has an issue. For whatever reason it is good to have something to hand to prevent damage to expensive test gear.

Therefore, this blog is designed to give instructions for you to build your own dummy load and attenuator. Maximum input power will be 10W so this is really for the QRP guys (why would anyone wish to use high power for test purposes?). It does, however cover a wide frequency range from 1Mhz – 500Mhz so is good for both the HF guys and the VHF guys.

Components:

R1 – R2 100R, 5W, 500V Metal Film

R3 – R6 620R, 600mW, 250V Metal Film

R7 – R8 100R, 0.5W, 350V Metal Film

PL1 – PL2 BNC sockets (or socket of your choice)

Looking at the diagram above it can be seen that this is a relatively easy project to construct. R1 and R2 are connected in parallel from the centre pin of the input connector directly to earth. This provides a 50 ohm load to the transmitter and a 1:1 SWR which will protect the finals. It will handle up to 10W but may get warm if this is for too long. R3 – R6 are connected in series between the two BNC connectors on the live side (centre pin – centre pin). The total resistance is 2.48k which presents a 40dB attenuation to the signal. R7 and R8 are again connected in parallel from the centre pin of the output BNC to earth to provide a 50 ohm load and protect both the transmitter and the test equipment.

Using the diagram as a guide build it how you wish but to prevent stray RF it is advisable to enclose it in a metal case.

Making Waves -Break downs and silver linings

It all began when something went wrong with my trusty Yaesu FTdx1200.  This being my main HF/6m radio what was I to do?  The screen had gone from displaying all the necessary information to enable QSOs to be made to simply being the white screen of death.

Pic1Fig 1. The Yaesu FTdx1200 white screen of death

Well, I tried doing a full reset but no change, I opened it up and reinserted all the ribbon cables relating to both the screen and the FFT-1 unit but still no change.  So it was time to first contact the dealer I had bought the radio from originally (5 years ago).  They told me that it was probably a screen fault and that the screen would need replacing at a cost of £167 plus labour at £60/hour. So I then phoned Yaesu UK who told me pretty much the same. OUCH!

I ordered a USB to RS232 (9 pin) cable from eBay to see if a software update would cure it. I also found an ICOM IC-746 on auction currently at £299, I put in a maximum bid just in case and, in the meantime, set up my stand by radio for HF – the FT-817ND.  I turned it on and tried to copy some CW but after the lovely DSP features and narrow filters available on the FTdx1200, it sounded like someone had left the barn door open and there were a hundred stations all working on top of each other. Not good at all.

In the meantime, the USB to RS232 lead arrived but, to my chagrin, was the wrong gender – I needed a female RS232 head and this was a male one.  So I ordered another, the other way around.  Whilst waiting for the new cable to arrive I watched the price of the IC-746 rising as others put bids in over the days.  None of them came to the level that I put in originally though and suddenly I am the winner of an eBay auction  for what was one of the radios I could only have dreamed of owning when they were available (very expensive back then).  The price – £344 plus £30 shipping, £374 altogether. So, I scrabbled around in my piggy bank for loose coins and paid for it.

The new (to me) IC-746 arrived five days later complete with a pair of headphones.

Pic2Fig. 2 The IC-746 

I now had to find somewhere in the shack to set it up..

It is a little smaller than the FTdx1200 but still weighs in at 11Kg so |I looked to set it up on the second bench in the shack.  Now this radio would give me something that the Ftdx1200 didn’t have – 100W output on 145mhz as well as HF/50MHz.  I do enjoy operating on 2m SSB and CW but I had another problem following the storms that struck the UK during February my rotator on my VHF mast has broken – it won’t turn so is fixed beaming south west. This will be a job when the weather improves as it means going 8m up a ladder in a tight spot. However, I did manage to find room for the IC-746 and get it set up for 2m using the beam.

Pic3Fig.3 The IC-746 running 144mhz USB and a FRG-9600 RX receiving local airport traffic.

Then the new USB-RS232 cable arrived, so I plugged it into both my laptop and the CAT port on the rear of the Yaesu and logged onto the yaesu.com website.  Following the instructions on the software update page I turned on the radio whilst pressing both the up and down arrow keys and presto – it came back to life.  Wow, that could have been an expensive repair for the sake of a software/firmware glitch! So now I have two HF sets and one good QRO VHF set.  The ICOM does seem more sensitive than the Yaesu at picking out weak signals on SSB and CW but misses out on some of the nice features of the Yaesu which is more a SDR than a traditional radio.  The ICOM does have a scratch in the centre of the screen but I can live with that.  How will they be used? Well, I will use the Yaesu for CW and contests on HF as I have it plugged into the linear amp whereas the ICOM will be used mainly for VHF and, once I get a second antenna up for HF, can be used for dual band monitoring.  I am currently using an antenna switch to switch between them so I can compare them both but this is never the best way.

73 until next time, M0CVO

Making Waves – Building the KANGA Products OXO Transmitter Kit (Part 2)

December 21, 2019 Leave a comment

2

Following on from yesterday when I started building this excellent kit from Kanga Products, I have today managed to build the rest of it, all that it needs now is a power source and a Low Pass Filter before it can be plugged into an antenna.  Neither of these are included of course but the power supply can be a simple 9V battery (or 12V PSU) and the LPF a simple 5 or 7 pole LC filter.

7The completed board

Overall the PCB was easily populated with the components and personally I shall add a polyvaricon to the terminal beside the XTAL labelled Cvar.  The option was to either bridge this and have the frequency rock set to the XTAL value or add a variable capacitor to enable a swing on the frequency.  Therefore I am going for the latter option.  If I have any criticism of the kit it is that the XTAL(s) supplied are in a large can – I would probably replace them with the smaller low profile ones – and they are supplied at 14.050 and 7.028MHz, not the QRP frequencies of 7.030 and 14.060MHz.  I am planning on designing/building a switched XTAL bank to allow operation on all the QRP frequencies from 80m – 20m (possibly 15m) using XTALs I have here.

 

I have yet to do a smoke test and check the stability of the RF generated yet but this will be in the next stage as I have other things to be doing now.  I shall be checking both with and without a LPF straight into a dummy load before I plug it into an antenna of any sort though.  I also need to find a suitable enclosure for it.

Making Waves – Building the KANGA Products OXO Transmitter Kit (Part 1)

December 20, 2019 Leave a comment

2

As it’s nearing Christmas 2019, I decided to treat myself to an OXO TX kit from Kanga Products UK.  This is an updated version of the OXO transceiver made famous by the late GM3OXX now providing a multi-band version.  So I ordered it from KANGA and it turned up here yesterday in a jiffy bag/envelope.  Taking it out it was nicely packaged in a sealed plastic sleeve.

1

Making sure I had all necessary test equipment ready (including the Sandford Wattmeter also from Kanga Products) I set to work to start assembling it on the CVO towers workbench.

Opening up the outer sleeve and removing the contents I was pleased to see that all the components were sorted in separate bags of resistors, capacitors, transistors, etc.  tis makes individual components much easier to find as opposed to just having everything dumped into a single bag.

3 everything sorted into individual bags

The instructions needed to be downloaded from the website and consisted of a three page .PDF file.  To quote one paragraph from them:

“Though the fitting of the parts is straight forward, it is highly recommended that all components are soldered in the order they are listed in the component list”

Although this may seem a no brainer it is good advice as you can then mark off each component as it is fitted and it runs in order of resistors, capacitors, transistors, crystals and then connectors.  This also follows the order of the bags.  My only criticism here is that the coil isn’t mentioned in the list but is mentioned in a separate paragraph.  It needs winding by hand and is 17 turns of 24SWG ECW wound on a very small ferrite toroidal core.  This is surface mount and laid flat on the PCB and should be mounted first ideally.

4The PCB is nicely printed and fairly easy to follow

5

So, contrary to my earlier advice I first fitted the resistors to the board.  Fairly easy through hole devices and Dennis, from Kanga UK, has kindly listed the colour coding of each resistor beside its value in the list.  Not really necessary for those of us in the know but for those not familiar with resistor colour codes a handy help.

6

Next I wound the coil.  The former is very small and this can be fiddly.  Note, if you are going to build one yourself do leave the ends long as if you cut them too short….  Anyway once wound I fitted the coil to the board using the plastic screw, washer and nut supplied before soldering the tails to the pads on the board.  Contrary to popular belief the enamel coating on the copper wire doesn’t melt away to reveal bare copper when you apply a soldering iron.  I use a Dremel Multi-tool to remove some of the enamel coating before applying solder.  Once this was secure I then applied the capacitors in order, with the large electrolytic one being fitted last of all, ensuring the polarity was correct.  that was it for today as work got in the way but I will continue when I next get round and will hopefully have it complete and ready to test next time.

C# WPF programming / my other side

October 21, 2019 Leave a comment

As well as antennas and radio I am also quite keen on coding/programming in C# for mainly Windows applications.  I started writing programs in the 1980’s using Commodore BASIC and moved on from there.  A few years ago (about 10) I picked up where I left off and started using Visual C# in Visual Studio.  Funnily, although I started out with BASIC, I just couldn’t get on with Visual Basic – a feeling I hear echoed amongst many of my friends and contacts – so I gave C# a go.

I started like most with the standard “Hello World” program:-

  • static void Main(string[] args)
  • {
    • Console.Writeline(“Hello World”);
  •  {

and then moved on to Windows Forms programming which was quite easy and self explanatory. Using Windows XP and Windows 7 (never touched Vista) Windows Forms were great and I created many small but useful programs, some of which I published through the Microsoft app store.  Then with the advent of Windows 8 Windows Store apps were more for the Windows Phone which, unfortunately was too late to the already flooded smartphone market and was later withdrawn.  Also around this time, I moved from using Windows Forms to using WPF in Visual Studio 2012.  What a difference! Gone were the square regimental blocks used in WinForms and suddenly transition between pages and windows was much more fluid and reasonable animation was possible.  However, it did mean also having to learn XAML.

WinFormsSample Windows Forms layout in VS2017

WPFSample.JPG WPF layout in VS2017, note the XAML beneath the design screen.

Then Windows 10 happened.  With Windows 10 the Windows Store became more difficult -apps had to be written in UWP(Universal Windows Protocol) format.  An absolute nightmare for most developers.  This was a much stricter protocol with limitations on what was allowed and , due to the many different form factors including PC Desktop, tablet, Phone, etc, it need to be able to resize without truncation.  So what now for all of us who had been happily writing software in WinForms or WPF?  Did this mean that we would have to learn UWP coding?

UWPSample UWP Layout in VS2017

Not at all it turns out.  Thankfully, if you upgrade to Visual Studio 2019 (even the Community Version) you can write your desktop apps using WPF in order to tweak them and perfect them ready for uploading to the Windows Store.  However, before you can you must first right click on the solution and add new project.  This should be a UWP blank app. There is no need to write any code for this project, just right click on the project and associate it with the app you have created in WPF.  Once you have done this right click on the UWP project that you have added and scroll down to publish and then create Windows Store App Package.  This will create a package that can be uploaded to the Windows Store (.appxupload, appxbundle, etc).

Of course, in all samples above, the result is the same, the message “Hello World” is displayed in the screen. However, in the first, console project the command to do so is

“Console.Writeline(“Hello World”);

in the Windows Form and WPF the command is

“MessageBox.Show(“Hello World”);

and in the UWP app the command is

“MessageDialog msg = new MessageDialog(“Hello World”);
msg.ShowAsync();”

Showing how each of the different packages differ in their command format.

Making Waves, New Opportunities, KW and beyond…..

September 28, 2019 Leave a comment

It has been a while since I have written anything on my blog but this is mainly because I have been rather busy.  The antenna business ( www.m0cvoantennas.com ) went from being busy to very busy at the beginning of the year and has remained so since.  In March of this year I was given the opportunity to take over as Director of K.W.Electronics Limited (Company #08587607).  progress was slow at first but in July 2019 I received certificates transferring over the title of Director to myself.

KW_Logo

KW Electronics was first founded in the 1950s by G8KW.  They produced many receivers, transmitters and accessories for the amateur radio market, the most famous being the KW Vanguard Transmitter that featured in Dr. No, the 1962 James Bond film as can be seen HERE.
Now under new ownership, KW Electronics Limited is all set to bring you new products aimed at the amateur radio and commercial radio market suitable for the 21st Century.
The first products introduced to the new KW Electronics company profile are a Morse Code Practice Oscillator, either completed and boxed or the same in kit form (not including the box.
DSC00716
The K.W.Electronics Morse Code Practice Oscillator available HERE
DSC00727
The K.W.Electronics Morse Code Practice Oscillator Kit available HERE
There are other things currently being worked on such as a VHF preamp and an all band active antenna (both for RX only).  We also currently have an all band HF antenna – the KW-V – which is the CHAD (Compact Helical Asymmetric Dipole) developed by Ken Ginn, G8NDL.  However, as we are awaiting some parts this is not currently available.
Full details of K.W.Electronics Limited can be found HERE.