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Before yesterdayM0AWS Amateur Radio

Getting back onto 160m β€œTop Band”

By: M0AWS
6 September 2023 at 08:11

Since setting up the new HAM station here in the UK the one band I’ve not yet got back onto is 160m, one of my most favourite bands in the HF spectrum and one that I was addicted to when I live in France (F5VKM).

Having such a small garden here in the UK there is no way I can get any type of guyed vertical for 160m erected and so I needed to come up with some sort of compromise antenna for the band.

Only being interested in the FT4/8 and CW sections of the 160m band I calculated that I could get an inverted-L antenna up that would be reasonably close to resonant. It would require some additional inductance to get the electrical length required and some impedance matching to provide a 50 Ohm impedance to the transceiver.

Measuring the garden I found I could get a 28m horizontal section in place and a 10m vertical section using one of my 10m spiderpoles. This would give me a total of 38m of wire that would get me fairly close to the quarter wave length.

For impedance matching I decided to make a Pi-Network ATU. I’ve made these in the past and found them to be excellent at matching a very wide range of impedances to 50 Ohm.

M0AWS Homebrew Pi-Network ATU
M0AWS Homebrew Pi-Network ATU

Since I still had the components of the Pi-Network ATU that I built when I lived in France I decided to reuse them as it saved a lot of work. The inductor was made from some copper tubing I had left over after doing all the plumbing in the house in France and so it got repurposed and formed into a very large inductor. The 2 x capacitors I also built many years ago and fortunately I’d kept locked away as they are very expensive to purchase today and a lot of work to make.

Getting the Inverted-L antenna up was easy enough and I soon had it connected to the Pi-Network ATU. I ran a few radials out around the garden to give it something to tune against and wound a 1:1 choke balun at the end of the coax run to stop any common mode currents that may have appeared on the coax braid.

Connecting my JNCRadio VNA I found that the Inverted-L was naturally resonant at 2.53Mhz, not too far off the 1.84Mhz that I needed. Adding a little extra inductance and capacitance via the ATU I soon had the antenna resonant where I wanted it at the bottom of the 160m band.

M0AWS 160m Inverted L Antenna SWR Curve
M0AWS 160m Inverted L Antenna SWR Curve

With the SWR being <1.5:1 across the CW and FT8 section of the band I was ready to get on 160m for the first time in a long.

Since it’s still summer in the UK I wasn’t expecting to find the band in very good shape but, was pleasantly surprised. Switching the radio on before full sunset I was hearing stations all around Europe with ease. In no time at all I was working stations and getting good reports using just 22w of FT8. FT8 is such a good mode for testing new antennas.

As the sky got darker the distance achieved got greater and over time I was able to work into Russia with the longest distance recorded being 2445 Miles, R9LE in Tyumen Asiatic Russia.

In no time at all I’d worked 32 stations taking my total 160m QSOs from 16 to 48. I can’t wait for the long, dark winter nights to see how well this antenna really performs.

M0AWS Map showing stations worked on 160m using Inverted L Antenna
M0AWS Map showing stations worked on 160m using Inverted L Antenna

The map above shows the locations of the stations worked on the first evening using the 160m Inverted-L antenna. As the year moves on and we slowly progress into winter it will be fun to start chasing the DX again on the 160m band..

UPDATE 6th October 2023.
Been using the antenna for some time now with over 100 contacts on 160m. Best 160m DX so far is RV0AR in Sosnovoborsk Asiatic Russia, 3453 Miles using just 22w. Pretty impressive for such a low antenna on Top Band.

More soon …

My old valve radio station

By: M0AWS
3 September 2023 at 11:35

Going through some old photos today I found a few great memories from the past of my old valve radio stations that I’d restored over the years.

These old radios gave me some wonderful moments over the years and a fair few hours of restoration to get them into operational condition. They sounded great on air and I often got comments from other amateur stations about how warm the audio sounded. Some did also mention the drift of the transmitter with temperature changes but, you just have to accept that when using vintage radio equipment.

M0AWS FT101E Transceiver, FL101 Transmitter, FR101B Receiver and TS520S Transceiver.
M0AWS FT101E Transceiver, FL101 Transmitter, FR101B Receiver and TS520S Transceiver.

Above is my old FT101 line up. It consisted of the great FT101E transceiver, a complete standalone solution that was extremely popular in its day. Below it is the FT101 line up made up of the FT101 transmitter, FR101B receiver and matching speaker.

Top right is the lovely Trio TS520S with the matching digital frequency display which is incredibly rare and very sought after today.

These radios gave me a lot of pleasure for many years and I wish I still had them today.

My second Yaesu valve line up took a lot more restoration than the 101 series and was quite challenging at times but, with a lot patience and time spent sourcing parts I got them back to as close to new operational condition as was possible.

M0AWS FLDX400 Transmitter, FRDX400 Receiver, FL2000B Amplifier and FTDX501 Transceiver.
M0AWS FLDX400 Transmitter, FRDX400 Receiver, FL2000B Amplifier and FTDX501 Transceiver.

The Yaesu 400 series line up consisted of the FLDX400 transmitter, FRDX400 receiver and was finished off with the FL2000B amplifier. These 3 pieces of radio equipment looked beautiful in the flesh and were wonderful to operate. Taking a good 15mins to warm up and become stable you couldn’t rush getting on air. This line up was my favourite by far even though they weren’t as good as the 101 line up.

Above the 400 series is the later FTDX501 transceiver with matching speaker. This was a great radio in its own right but, not as much fun to operate as the 400 line up. To the right of the FTDX501 is the matching Yaesu Microphone for the 400/500 series. This mic is incredibly rare and I had to visit many radio swap rallies to find it, worth the effort though.

Top right you can see my old SWL receiver, the great Drake SW4A. I never had a Drake line up as they are quite rare in the UK but, it certainly would had made a great addition to the station.

M0AWS FLDX400, FRDX400 & FL2000B Station being operated by M1ACB and G6ALB
M0AWS FLDX400, FRDX400 & FL2000B Station being operated by M1ACB and G6ALB

Finally this is a photo of two friends of mine, Steve Thomas M1ACB (Current General Manager of the RSGB) on the right and Andy, G6ALB with whom I spent many hours sending and receiving morse with to get our Class A licences. We had a fun day together operating the old radios and taking it in turns to handle the pile ups!

More soon …

Antenna Analysers – The New World

By: M0AWS
1 July 2023 at 19:23

Many years ago I had an MFJ-259B antenna analyser that I used for all my HF antenna projects. It was a simple device with a couple of knobs, an LCD display and a meter but, it provided a great insight into the resonance of an antenna.

MFJ-259B Antenna Analyser
MFJ-259B Antenna Analyser

Today things have progressed somewhat and we now live in a world of Vector Network Analysers that not only display SWR but, can display a whole host of other information too.

Being an avid antenna builder I’ve wanted to buy an antenna analyser for some time but, now that I’m into the world of QO-100 satellite operations using frequencies at the dizzy heights of 2.4GHz I needed something more modern.

If you search online there are a multitude of Vector Network Analysers (VNAs) available from around the Β£50.00 mark right up to Β£1500 or more. Many of the VNAs you see on the likes of Amazon and Ebay come out of China and reading the reviews they aren’t particularly reliable or accurate.

After much research I settled on the JNCRadio VNA 3G, it gets really good reviews and is very sensibly priced. Putting a call into Gary at Martin Lynch and Sons (MLANDS) we had a long chat about various VNAs, the pros and cons of each model and the pricing structure. It was tempting to spend much more on a far more capable device however, my sensible head kicked in and decided many of the additional features on the more expensive models would never get used and so I went back to my original choice.

Gary and I also had a long chat about building a QO-100 ground station, using NodeRed to control it and how to align the dish antenna. The guys at MLANDS will soon have a satellite ground station on air and I look forward to talking to them on the QO-100 transponder.

Getting back to antenna analysers, I purchased the JNCRadio VNA 3G from MLANDS at Β£199.96 + postage and have been trying it out on a couple of antennas here at the M0AWS QTH.

M0AWS - JNCRadio VNA 3G Packaging
M0AWS – JNCRadio VNA 3G Packaging
M0AWS - JNCRadio VNA 3G in box with connectors and cables
M0AWS – JNCRadio VNA 3G in box with connectors and cables

Initially I wanted to check the SWR of my QO-100 2.4GHz IceCone Helix antenna on my satellite ground station to ensure it was resonant at the right frequency. Hooking the VNA up to the antenna feed was simple enough using one of the cables provided with the unit and I set about configuring the start and stop stimulus frequencies (2.4GHz to 2.450GHz) for the sweep to plot the curve.

The resulting SWR curve showed that the antenna was indeed resonant at 2.4GHz with an SWR of 1.16:1. The only issue I had was that in the bright sunshine it was hard to see the display and impossible to get a photo. Setting the screen on the brightest setting didn’t improve things much either so this is something to keep in mind if you plan on using the device outside in sunny climates.

(My understanding is that the Rig Expert AA-3000 Zoom is much easier to see outside on a sunny day however, it will cost you almost Β£1200 for the privilege.)

A couple of days later I decided to check the SWR of my 20m band EFHW vertical antenna. I’ve known for some time that this antenna has a point of resonance below 14MHz but, the SWR was still low enough at the bottom of the 20m band to make it useable.

Hooking up the VNA I could see immediately that the point of resonance was at 13.650Mhz, well low of the 20m band and so I set about shortening the wire until the point of resonance moved up into the band.

JNCRadio VNA3G showing 20m Band EFHW Resonance
JNCRadio VNA3G showing 20m Band EFHW Resonance

With a little folding back of wire I soon had the point of resonance nicely into the 20m band with a 1.35:1 SWR at 14.208Mhz. This provides a very useable SWR across the whole band but, I decided I’d prefer the point of resonance to be slightly lower as I tend to use the antenna mainly on the CW & FT4/8 part of the band with my Icom IC-705 QRP rig.

Popping out into the garden once more I lengthened the wire easily enough by reducing the fold back and brought the point of resonance down to 14.095Mhz.

JNCRadio VNA3G showing 20m Band EFHW Resonance 14Mhz to 14.35Mhz Sweep
JNCRadio VNA3G showing 20m Band EFHW Resonance 14Mhz to 14.35Mhz Sweep

The VNA automatically updated the display realtime to show the new point of resonance on the 4.3in colour screen. I also altered the granularity of the SWR reading on the Y axis to show a more detailed view of the curve and reduced the frequency range on the X axis so that it showed a 14Mhz to 14.35Mhz sweep. With an SWR of 1.34:1 at 14.095Mhz and a 50 Ohm impedance, the antenna is perfectly resonant where I want it.

It’s interesting to note that the antenna is actually useable between 13.5Mhz and 14.5Mhz with a reasonable SWR across the entire frequency spread. Setting 3 markers on the SWR curve I could see at a glance the SWR reading at 14Mhz (Marker 2) , 14.350Mhz (Marker 3) and the minimum SWR reading at 14.095Mhz (Marker 1).

M0AWS 20m Band EFHW Vertical Antenna 13.5MHz - 14.5Mhz SWR Curve
M0AWS 20m Band EFHW Vertical Antenna 13.5MHz – 14.5Mhz SWR Curve
M0AWS 20m Band EFHW Vertical Antenna SWR curve 14Mhz - 14.350MHz
M0AWS 20m Band EFHW Vertical Antenna SWR curve 14Mhz – 14.350MHz

I’ve yet to delve into the other functionality of the VNA but, I’m very happy with my initial experience with the device.

More soon …

First full power day on QO-100

By: M0AWS
12 June 2023 at 20:29

The male to male SMA connector that Neil, G7UFO kindly posted to me arrived late this afternoon and I wasted no time getting it connected between the 2.4Ghz up-converter and the 12w amplifier.

Male to Male SMA connector for QO-100 Ground Station
Male to Male SMA connector for QO-100 Ground Station

Initially when I powered up the 12v to 28v converter board the output voltage was only showing 22v and so I had to adjust the onboard variable resistor to get the voltage closer to the recommended 28v for the amplifier. I decided to run the amplifier at 27v so that it wasn’t being pushed to it’s full and so readjusted the voltage converter back down to 27v. This seems to work very well with the amplifier not getting very warm at all during use.

M0AWS QO-100 2.4Ghz Uplink Hardware.
M0AWS QO-100 2.4Ghz Uplink Hardware.

Getting on air I was really impressed at how strong my signal was on the 10Ghz downlink. With my own signal peaking 5/9+10dB I was very happy with the performance of the ground station.

I made a few contacts very quickly with the first being OH5LK, Jussi from Helsinki Finland. Jussi was actually the first station I worked on CW too when I was running just 200mW, it was great to have him for both of my first contacts on QO-100.

I then went on to work a few stations from Wales, Germany, Poland and Belgium but, the one that I was totally shocked to get on my first real day of QO-100 operations was ZD7GWM, Garry (HuggyBear) on St. Helena Island, South Atlantic Ocean. This is an Island that I have never had a contact with before on any band and so I was extremely happy to get a new first especially on my first QO-100 day.

Garry and I chatted for some 25 minutes covering many topics, it was great to have an armchair copy over such a distance, something that would be impossible on the HF bands. What a great way to start my QO-100 satellite career!

One of the things I really like about the operators on QO-100 is that they have time to stop and chat, this is so refreshing and a rarity today. I’m really going to enjoy this satellite.

You can see all the details of my QO-100 contacts in my Online Satellite log.

More soon …

My First QO-100 Satellite QSO

By: M0AWS
10 June 2023 at 17:29

I’ve been waiting for over a week so far for a male to male SMA connector to arrive from Amazon so that I can connect the 2.4Ghz up-converter to the 2.4Ghz amplifier. Since it still hasn’t arrived I decided to connect the up-converter directly to the IceCone Helix antenna to see if I could get a signal into the QO-100 satellite.

To my surprise I could easily hear my CW signal on QO-100 even though the total output from the up-converter is only 200mW.

I didn’t expect to be able to hear my signal since it’s a tiny amount of power that has to travel some 22500 miles to the satellite but, I could hear it and was amazed that it was peaking S8 on my SDR receiver.

2.4Ghz Up-COnverter connected directly to the antenna bypassing the 2.4Ghz Amplifier
2.4Ghz Up-Converter connected directly to the antenna bypassing the 2.4Ghz Amplifier

Being excited I put out a CQ call that was soon answered by OH5LK, Jussi in Finland. Jussi gave me a 579 report which I was extremely pleased with. He was of course much stronger at a 599+ at my end. We had a quick QSO and exchanged details without any problems at all. Its really nice to get a QRPp contact without any QSB or QRM.

M0AWS QO-100 1.1m off-set Dish and IceCone Helix antenna ground station
M0AWS QO-100 1.1m off-set Dish and IceCone Helix antenna ground station

Neil, G7UFO who I chat with regularly in the Matrix Amateur Radio Satellites room has posted a connector out to me so I’m hoping it will arrive on Monday and then I’ll be able to connect the amplifier and hopefully get a few SSB contacts.

UPDATE: I’ve since had 2 SSB contacts via QO-100 using just the 200mW O/P from the up-converter. Both times I got a 3/3 report not brilliant but, perfectly acceptable for the amount of power I’m putting out.

More soon …

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