Audio – M0AWS Amateur Radio

23 August 2026

Building MB7IBW 2m AllStarLink Internet Gateway

I’ve recently built another AllStarLink node to compliment my personal 70cm band SHARI node as I thought since I have a full duplex dual band handheld it would be great to have another node that I could connect to FreeStar or HUBNet at the same time as monitoring the Matrix node.

Rather than build another personal node I decided this time I would build a public node, obtain a callsign from the RSGB and make it available to the HAM’s locally on the 2m band.

This would make it possible for me to monitor both nodes at the same time using my Wouxun KG-UV9K full duplex dual band handheld whilst providing the local HAM community with access to the AllStarLink network.

Initially I thought I may be able to use my old Retevis RT85 handheld and AIOC board for the 2m node but, after a little testing it soon became apparent that it overheats during long overs (which are common on AllStarLink) and so, I needed to find another solution.

Chatting about this in the main Matrix HAM Radio room Steve, M0XVT sent me a message saying he had an old Key KM-4000 converted PMR radio that had been reprogrammed for the 2m band that he was looking to sell and that it might be ideal for the new node. Wasting no time, we came to an agreement and I was soon the proud owner of a converted PMR transceiver.

The KM4000 transceiver has a standard output of 15w, 10w more than I needed for the gateway and so I had to reduce the output. A quick search on the internet and I found the Thames Valley Repeater Group website that had all the information required to turn down the output.

I also had to reprogramme channel 1 to the frequency and CTCSS tone allocated to me by the RSGB so that in the event of a power outage when the radio came back on it automatically jumps to channel 1 which would be correctly setup for operation.

Unfortunately the software for programming the radio is only available for windows and so I had to build a virtual machine running windows 10 to be able to reprogramme the radio.

Once this was done I rewired the AIOC USB audio device to work with the KM4000 radio and built the AllStarLink node on a spare RaspberryPi 4.

For an antenna I made a simple end fed vertical dipole from some RG58 coax and mounted it 8m up on one of my Spiderpoles in the garden. Running a coax feed out to the antenna I did some tests into the Parrot to get the audio levels setup and checked that the DTMF codes were interpreted correctly and that the node switched connections without error.

MB7IBW Internet Gateway hardware at the M0AWS QTH

Once this was done I had a few test conversations with stations on the Matrix node and FreeStar to ensure all was fine and then set the gateway status to “Operational” on the RSGB website.

This worked fine for a while with myself and some local stations using the node regularly but, then the hot weather arrived and things started to overheat. The transceiver was getting incredibly hot in the 30c+ summer temperatures and the power supply was also running extremely hot and so I decided to add some cooling.

Cooling the PSU was simple, it has a perforated top panel to which I strapped a cooling fan. This worked great and brought the temperature of the PSU down considerably.

The radio wasn’t so easy to cool. It has a solid case cover top and bottom and so cooling wasn’t going to be a simple affair.

I decided to remove the covers and drill some holes into them to allow airflow through the unit and strapped a fan to the top cover to pull the hot air out. This worked well however, on both transmit and receive I now had a warbling sound on the audio that was caused by the motor of the fan when powered up.

I found that lifting the fan up away from the case of the radio the warbling audio disappeared and things were back to normal and so, I decided to design a cooling tube to fit to the top of the radio to allow full airflow from the fan but, with the fan raised up away from the radio to resolve the audio problem.

Jumping into my CAD software I quickly designed a cooling tower to fit on the top of the radio that would allow the fan to sit far enough away from the radio so as to not affect the audio whilst at the same time pulling the hot air out of the radio and drawing cooler air in through the bottom of the case.

I sent the design through to my Bambu Lab A1 Combo 3D printer and set the print job running.

The cooler worked great with the radio staying cool to the touch and no longer overheating and reducing O/P power.

It’s amazing how much dust and dirt is in the air from all the farming activities going on at the end of our garden and how much of it is sucked in by the cooling fan. Regular cleaning is a must!

The MB7IBW Internet Gateway has been on air since mid June 2026 and has worked well. It spends most of its time connected to either FreeStar or HUBNet with connections to the Matrix Node when we have our nets.

Details on Frequency, CTCSS etc can be found under the MB7IBW menu above.

Sadly the initial interest from local HAMs has now wained and I am mostly the only user of the gateway. I was hoping more people would use it and bring some life to the 2m band, I guess time will tell.

It’s been a fun project and was interesting to go through the callsign allocation process with the RSGB representative. It was much easier than I thought it would be.

I now have all the parts to build another Internet Gateway for the 4m band. Hopefully that may attract some more interest. It’s certainly worth a try!

More soon …

8 June 2026

Short skip on 20m

Yesterday morning I ventured up onto the 20m band and to my surprise, found that the band was open to inter-G, unusually short skip for the 20m band.

Wanting to take advantage of the conditions I kicked off with a QSO with David, MI0AIH in Cookstown Northern Ireland. With 59+ signals both ways, it was like being on 40/60/80m with a crystal clear path between us.

Next was GB0BBF operating POTA GB-0619, again 59 both ways and a really easy contact.

My third contact was with Aled, MW0UPH who was parked up in his car on a hill in North Wales. The path between us was incredibly good. With 59 signals both ways and an FM like arm chair copy, we chatted for a few minutes making the most of the short skip.

Aled very kindly made a quick video of our conversation and sent a copy over to me to watch. It’s always nice to hear what you sound like on the other end.

M0AWS as heard by MW0UPH on the 20m Band

Unfortunately I didn’t think to make a video of the conversation at my end but, it was exactly the same, crystal clear arm chair copy, just like a 2m FM contact.

It was great fun working UK stations on a band that I would normally only ever hear EU and DX stations. It was interesting to note that Inter-G on 40m was really poor at the same time.

Thanks to Aled for the video.

More soon …

2 May 20262 May 2026

Bring your old handheld to life with an AIOC

I’m sure there are many radio amateurs around the world today who have an old handheld radio sat on the shelf that works perfectly but, has been replaced by a new, shiny, all singing, all dancing model that gets used on a daily basis. I for one have fallen into this trap with the recent purchase of a very nice Wouxun KG-UV9K full duplex 2m and 70cm handheld.

On my shelf there is a cheap Retevis RT85 that gave sterling service for a number of years and even today is ready to continue that service, if only I had a need?

Well now I do!

Currently I have an AllStarLink node running on a RaspberryPi 3b connected to a SHARI device that operates on the 70cm band. This node works great and gives me the ability to chat with people all over the world from my trusty handheld. It does of course also give me access to the weekly Matrix AllStarLink Net that happens on our Matrix node ( 642332 ) every Thursday evening at 20:00 UK time, a great way of bringing the Matrix HAM Radio community together regardless of propagation.

For some time I’ve been wanting to bring another AllStarLink node online so that I can have a connection to HUBNET/FreeNet whilst keeping my current node connected to the Matrix node for our regular daily chats. Since my new Wouxun handheld is a full duplex unit it makes sense to bring a new node up on the 2m band as I can then monitor both at the same time easily. I do have a spare SHARI node however, it’s a UHF only unit and I don’t want another node on the 70cm band. This is where the old Retevis RT85 comes in to play.

The All In One Cable ( AIOC ) board is a very neat little CM108 compatible sound card and serial interface that is sold by Steve, KM9G of YouTube fame ( Temporarily Offline ) that plugs into any handheld radio that has the now pretty much standard Kenwood ‘K’ type mic connector.

The AIOC board really is tiny but, beautifully put together. The four large solder pads on the top and more on the underside are positioned such that the TRS plug solder lugs line up perfectly for soldering. Attempting to do this by hand would be impossible as it’s critical that the spacing between the two connectors matches that of the spacing of the sockets on the radio.

Searching online I found a very handy soldering jig on Github that enables you to hold both the TRS connectors and AIOC board in the perfect position for soldering.

Downloading the .STL file I quickly printed off a solder jig on my Bambu Lab A1 Combo 3D printer and fitted the components into place ready for soldering.

Fitting TRS connectors into the AIOC solder jig

Fitting AIOC board into the solder jig. — Fitting TRS connectors into the AIOC solder jig

Everything fitted rather snugly into the jig and I soon had the board and connectors soldered together. Test fitting to my Retevis RT85 I found the TRS plugs lined up perfectly and it slid into the sockets with ease.

I then thought about designing a case for the AIOC board so that the bare circuit was nicely protected but, quickly searched online and found that NA6D has already designed a case and made the .STL available publicly for download on Printable.com. I quickly grabbed a copy of the file and punted it off to my 3D printer to get to work on.

Once the print was complete I fitted the AIOC board and snapped it together ready for testing.

Fitting the AIOC into the 3D printed case.

AIOC case with 2 x TRS connectors in place. — Fitting the AIOC into the 3D printed case.

Now that the AIOC was production ready I moved on to getting the latest version of AllStarLink onto my RaspberryPi 4 that I had taken out of my RadioBerry based shortwave receiver that I am going to upgrade to a Hermes Lite 2 in a later project. The RaspberryPi 4 is perfect for AllStarLink 3, a 64bit app and operating system.

Using the RaspberryPi Imager I pulled the image down onto an SD card and slipped it into my Pi4. ( Instructions on how to do this are on the AllStarLink website here )

Booting the Pi4 for the first time I found that it went through a number of reboot and configuration cycles before it was ready for use.

Once ready I went through all the normal configuration of the Pi4 namely, static IP assignment, timezone config, security, port forwarding etc etc.

Having configured an AllStarLink node for myself and only just a few days ago for another HAM I was pretty familiar with the setup. Wanting to make sure there were no “gotcha’s” I also watched a couple of KM9G’s videos on Youtube to make sure I wasn’t missing anything.

Using the asl-menu command line app as user root I set about configuring Asterisk to work with the AIOC board. Much to my frustration I could not get Asterisk to recognise the AIOC board as an available sound device. I checked and double checked all the settings ensuring that I had selected “AIOC” in the available devices menu but found that Asterisk constantly errored saying it could not find the selected audio device. This went on for a whole day without success and so, I decided to put it to one side and come back to it later, a method I found that often worked.

A couple of days later I revisited the problem and had decided to take a different approach. Rather than continue going through the asl-menu app I decided to drop down to a lower level and go through the asterisk config files in the /etc/asterisk directory.

It wasn’t long before I found a file called res_usbradio.conf. Inside this file was the config for the AIOC board however, it was all commented out which meant it was disabled.

I’m guessing here but, I imagine this is what should get enabled when selecting AIOC in the available devices menu in the asl-menu command line app but, for some reason it doesn’t happen.

[general]
;usb_devices = 1209:7388    ;comma delimited list of usb
                            ;descriptors to allow.
                            ;format vvvv:pppp in hexadecimal
                            ;vvvv=vendor id, pppp=product id
                            ;
                            ;1209:7388 = AIOC (all in one cable)

Above is the disabled configuration which is easily edited to enable the AIOC device as shown below.

[general]
usb_devices = 1209:7388    ;comma delimited list of usb
                            ;descriptors to allow.
                            ;format vvvv:pppp in hexadecimal
                            ;vvvv=vendor id, pppp=product id
                            ;
                            1209:7388 = AIOC (all in one cable)

Once the updated file had been saved and I restarted Asterisk using systemctl the AIOC burst into life and Asterisk recognised it immediately. The Retevis RT85 switched between TX and RX and I was ready to check out the audio.

Setting the volume levels for both RX and TX via the command line tuning app I connected the node to my already existing node. Sure enough the two nodes connected without error and I was able to send and receive audio between them via the AllStarLink net.

Connecting the new node to the parrot I checked the audio levels to ensure it sounded ok and then connected it to the Matrix node where I had a brief chat with Ben, M8TKK.

All that is left to do now is to 3D print a case for the Pi4 so that it isn’t left naked and at risk of being shorted out on conductive surfaces and it’ll be ready for service.

I also plan to build another AllStarLink node using a 4m band handheld and another AIOC board and then will apply for MB7Ixx callsigns for the two new nodes. This will hopefully help to bring some life to the 2m/4m bands locally and introduce HAM’s both to the weekly Matrix Net and HUBNet/FreeStar via AllStarLink.

More soon …

30 March 20269 April 2026

ISS Astronaut talks to UK students

Students at the Simon Langton Grammar School for Boys in Canterbury, Kent UK, today had the opportunity to talk to astronaut Jack Hathaway, KJ5NIV, aboard the International Space Station (ISS).

Checking the ISS pass data I could see it was going to be a good pass for me to listen and so I setup my Wouxun KG-UV980P quad bander on 145.800Mhz to see if I could hear Jack.

Having only a Diamond V2000 vertical antenna, I don’t have the best station for satellite communications however, it has worked well in the past.

Sure enough, as the ISS approached the UK from the South West and reached 2deg above the horizon the signal started coming through. Below is the video I took of the pass.

I ended the video at 6min and 35sec as I thought I’d lost the satellite as it was out to the East over Russia and blocked by farm buildings near my QTH however, once I stopped videoing I remembered to move the VFO down 5Khz and sure enough I was able to hear the ISS right up until the point that Jack signed and ended the QSO.

I really should try to see if I can get some QSO’s via the ISS FM Repeater as the received signal really is very good. Whether the transmitted signal would be as good remains to be seen.

More soon …

14 December 202515 December 2025

FreeDV audio routing with PiHPSDR and Hermes Lite 2

I’ve recently been trying out the FreeDV RADEv1 digital voice mode on the HF bands with great success. The audio quality is astounding when compared to the normal analog SSB mode. Using only 20w I’ve been surprised how successful I’ve been talking to stations in the UK and Europe as can be seen in my FreeDV Log.

FreeDV has been around for quite a few years with development being funded by an ARDC grant and financial sponsorship from the Software Freedom Conservancy.

So what is FreeDV?

To quote the FreeDV website:

“FreeDV is a suite of digital voice modes for HF radio. Our flagship mode is the Radio Autoencoder (RADE). You can run RADE using a free GUI application for Windows, Linux and macOS that allows any SSB radio to be used for high quality digital voice.“

And the most important part:

“All software is open source, released under the (a) GNU Lesser Public License version 2.1 (GUI and legacy FreeDV modes) and two-clause BSD license (RADE).“

FreeDV running under KDE-Plasma on Kubuntu PC

Looking at the digital voice (DV) community in the HAM Radio world, it’s stuffed full with proprietary DV modes from small software houses and black box transceiver manufacturers with no real OpenSource alternatives, until now.

Installing FreeDV is pretty simple regardless of which operating system (O/S) you use. Being a Linux user I grabbed the AppImage from the website and set about reading up on how it works and how it is configured.

I decided to take the two sound card approach since I have 2 USB sound cards connected to my shack Kubuntu Linux PC.

Configuring the audio routing isn’t straight forward as both the receive and transmit audio to/from the radio needs to be routed via the FreeDV app. To make this even more complicated I am using my Hermes Lite 2 SDR transceiver and PiHPSDR software, a complete OpenSource/OpenHardware Amateur Radio Station.

M0AWS FreeDV and PiHPSDR Audio Routing Diagram

Trying to clearly describe the audio routing using words alone would be impossible and very confusing so, I put together the diagram above.

Using two USB sound cards I’ve configured the system such that USB Sound Card 1 (an old Griffin iMic USB sound device) handles just the audio from/to the headphones and microphone. All the audio at this point in the system is analogue.

The second USB sound card, a cheap Plug and Play (PNP) USB audio device from Amazon, handles all the digitised signals from/to FreeDV and PiHPSDR.

Taking this 2 sound card approach keeps confusion to a minimum and separates the analogue and digital components of the audio routing.

So, how does this translate to the FreeDV and PiHPSDR audio settings?

Transmit Audio Chain

FreeDV Transmit Audio Settings

Starting at the beginning of the transmit audio chain, let’s look at the transmit audio settings in FreeDV.

Looking at the FreeDV Transmit audio settings screenshot below we can see that the
Input From Microphone to Computer device is set to:

alsa_input.usb-Griffin_Technology_Inc_iMic_USB_audio_system-00.analog-stereo

This is the microphone connection on the iMic USB device (USB Sound Card 1) and is the analogue transmit audio input to FreeDV.

The Output From Computer to Radio device is set to:

alsa_output.usb-0c76_USB_PnP_Audio_Device-00.analog-stereo

This is the digitised audio output from FreeDV (via USB Sound Card 2) to PiHPSDR and is used as the transmit audio that is sent to the Hermes Lite 2 transceiver.

PiHPSDR Transmit Audio Setting

To complete the transmit audio path we next need to look at the PiHPSDR transmit audio setting.

As can be seen in the screenshot above, the Local Microphone device in PiHPSDR is set to the Monitor of USB PnP Audio Device Analogue Stereo.

This effectively routes the digitised output audio from FreeDV (Output From Computer to Radio device) to the Input audio of PiHPSDR.

The reason for using the Monitor audio feed is because FreeDV does not recognise the Mic Input in PiHPSDR as a valid output device for FreeDV to use, hence we just need to monitor the FreeDV output device and use it as our input audio device in PiHPSDR.

This completes the transmit audio chain.

Receive Audio Chain

PiHPSDR Receive Audio Setting

Starting at the beginning of the receive audio chain we first look at the PiHPSDR receive audio setting.

In the screenshot above we can see that the receive audio output from PiHPSDR is set to
USB PnP Audio Device Analogue Stereo (USB Sound Card2). This is the DX station’s digitised audio as received by the Hermes Lite 2.

FreeDV Receive Audio Settings

Next let’s look at the receive audio setting in FreeDV.

The Input To Computer from Radio device is set to the monitor of the
USB PnP Audio Output Device:

alsa_output_usb_0c76_USB_PnP_Audio_Device-00.analog-stereo.monitor

This effectively routes the digitised audio output from the PiHPSDR receiver to the digitised audio input of FreeDV.

Once again we have to use the monitor of the USB PnP Audio Output device as FreeDV does not recognise the PiHPSDR output as a valid input device.

Next, the Output From Computer To Speaker/Headphones device is set to:

alsa_output.usb-Griffin_Technology_Inc_iMic_USB_audio_system-00.analog-stereo

This is the analogue audio output on the iMic USB Sound card (Sound Card 1) that routes the analogue audio to the headphones and completes the receive audio chain.

Summary

The audio routing required by FreeDV can appear very daunting when first attempting to configure it on the Linux platform but, hopefully the diagram and screenshots above will help in understanding the complete end-to-end audio chain that is required to make this mode work.

PiHPSDR can of course be replaced by your black box radio CODEC entries that will appear in the device lists shown above if you have your radio connected via USB. The config is basically the same but, just uses a different device instead of USB sound card 2 shown in the diagram above.

I hope this article is useful to those wanting to try FreeDV on the Linux platform and I look forward to hearing you on RADEv1.

More soon …

9 March 202521 June 2025

Hermes Lite 2 Audio

I often get unsolicited good audio reports whilst using my Hermes Lite 2 (HL2) on the HF bands with people asking what settings I am using so, I thought it was time I put together an article on the subject.

I use the DL1YCF enhanced fork of PiHPSDR to drive my HL2, a great OpenSource SDR software package that supports many SDR radios including some very high end, expensive models.

PiHPSDR is extremely configurable via it’s well laid out menu system. It’s possible to change the settings on almost everything which, when combined with really good hardware like the HL2 gives the operator the ability to create an extremely high spec transceiver at a fraction of the price of the typical black box commercial offerings.

Starting at the beginning of the transmit audio chain the first settings to be changed are in the Transmit (TX) menu.

Using my Sennheiser headset I found I needed to set the Radio Mic setting to Mic Boost. This increases the audio level so that it drives the radio properly. It’s important to make sure that boosting the audio doesn’t cause distortion though.

Next I set the TX Filter Low to 150Hz. This ensures I don’t have that nasty bass sound that you hear often on the HF bands today.

The TX Filter High is set to 2700Hz. This gives me a transmit filter width of 2550Hz which is well within the 2700Hz standard for the HF bands.

I also set the compression level to +10dB to increase the average talk power of the audio.

Next in the transmit audio chain is the TX Equalisation. The PiHPSDR software has a very good software defined Parametric EQ menu that provides all the audio tailoring capabilities any HAM operator will ever need.

Having watched many videos by the great Bob Heil, K9EID (SK) I understand that all the articulation in the voice is around the 2500hz range. Today on the HF bands you often hear bass heavy audio that sounds muddy and horrible. This is exactly the type of audio I don’t want to have so, to this end I have adjusted my EQ settings such that the articulation is accentuated to increase clarity and give a little pep to my rather dull sounding voice.

Since the transmit filter width is set from 150Hz to 2700Hz there’s really no point in making EQ adjustments outside of this range. As show above I have made the following changes to the transmit EQ settings in PiHPSDR:

Frequency	Gain
150hz	+6dB
500Hz	+5dB
1500Hz	+6dB
2500Hz	+6dB

The final part of the audio setup is the Mic Gain, I keep this set at 5. This keeps the audio nice and tidy with no IMD.

My HL2 TX Drive is set so that it puts out a maximum of 500mW, this is enough to drive my Xiegu XPA125B amplifier to 100W.

With these settings I find that the Sennheiser headset, PiHPSDR software and the Hermes Lite 2 combination gives me a great signal on all the HF bands.

I hope this helps all those who have asked how my audio is setup and have been so impressed by this great little radio.

More soon …

29 January 202529 January 2025

Breathing new life into a vintage receiver

Sometime back I purchased a RadioBerry HAT for my RaspberryPi 4 single board computer (SBC) to use as an experimental platform to test PiHPSDR software modifications and to test changes to the actual RadioBerry software. With these two projects completed I decided that the receiver on the RadioBerry was so good it would be a shame not to put it to good use.

For many decades I’ve been an avid Short Wave Listener (SWL) but, haven’t had a general coverage receiver for many years. The RadioBerry fills this gap in my radio lineup perfectly but, needs to be put into a suitable cabinet with speakers, display, control knobs and antenna connections.

Rather than just buy another bland square box I decided it would be nice to repurpose an old, vintage radio receiver from a bygone era and bring it into the 21st Century.

1950 Philips valve radio receiver — 1946 Philips valve radio receiver

After much searching on the popular auction sites online I eventually found the perfect old receiver for the project, a vintage Philips 170A-15 valve receiver from 1946.

This lovely old Art Deco looking receiver is made from Bakelite which was an early type of plastic made from phenol-formaldehyde resin, obtained from coal tar and methanol.

The full specification for the receiver can be found on the Radio Museum Website.

Sadly this is a non working example of this lovely old receiver and so I don’t feel so guilty stripping it out and replacing it’s internals with the RadioBerry.

1946 Philips receiver Serial Number plate

1946 Philips receiver Licence Plate — 1946 Philips receiver Serial Number plate

Having the original serial number and Licence plate on the radio is nice, it also makes it easy to search for information about the old receiver.

One nice thing I did discover during the disassembly of the receiver was the signature of the person that put the radio together during manufacture on the inside of the Bakelite cabinet.

Getting the internals out of the cabinet was fun, so many little screws holding the old valve electronics and tuning display in place.

1946 Philips Receiver - Internal View — 1946 Philips Receiver – Internal View

1946 Philips receiver - removing the original control knobs — 1946 Philips Receiver – Internal View

Once the electrical part of the radio was removed I gained access to the old speaker that was fitted to the front panel of the receiver. Unfortunately the speaker cone had a tear in it rendering it useless so I’ll need to get a new speaker(s) for the rebuild.

Once I got the speaker and fittings removed I set about cleaning the cabinet inside and out to remove the 79 years worth of dirt and grime that had collected within. The fascia of the receiver cabinet seems to have lost it’s shine and will need to be polished to get it back to it’s original beauty.

79 years worth of grime and dirt to be removed!

Washing the Bakelite receiver case — 79 years worth of grime and dirt to be removed!

It took 5 lots of fresh water and washing up liquid to get the cabinet clean. The first three lots of water looked like mud in no time at all such was the state of the cabinet.

With the cabinet now cleaned and put to one side to dry thoroughly I have started to search for the best type of polish to use to put the sheen back onto it.

Once I’ve got the cabinet looking good again I’ll start fitting the new internals. I also need to find a source for a new piece of material to cover the speaker hole at the front of the cabinet as the original material is looking somewhat tired.

The old Philips Emblem from 1946 on the receiver case

More soon …

19 November 202429 November 2024

Another new radio!

Many years ago when I lived in France I had a Flex-3000 transceiver, one of the first fully SDR transceivers on the market. It was paired with a proprietary Windows XP application called PowerSDR (now Opensource and called Thetis) and connected via a firewire connection.

17 years later I am once again venturing into the world of SDR transceivers in the form of a Hermes Lite 2. (HL2)

The HL2 hardware is available via the Makerfabs website in kit form. I ordered the HL2 motherboard, the N2ADR Filter Board to ensure a clean signal from the transceiver and the enclosure. Total cost for all the parts and shipping was £288.00 including all taxes.

The kit took about 10 or so days to arrive and was very easy to put together making sure to fit the PA transistor heat sink the right way round so that it doesn’t short out the main board. (There are many videos about this on YouTube)

Once the hardware was put together I needed to install some software to control/drive the HL2. Being a heavy weight Linux user my software choice had to come from the Opensource world.

M0AWS Hermes Lite 2 SDR Trasnceiver and Xiegu XPA125B Amplifier

After much research and chatting with other HAMs on the Matrix who have the HL2 I found that most people use the closed source SDR Console software to control the transceiver. Since this software is for Windows it’s not something I can use as I don’t have any Windows PCs, they’re all Linux only.

To this end I started researching Linux SDR software for the HL2 and decided that PiHPSDR was the one I was going to try first.

PiHPSDR was originally written for the RaspberryPi 3/4/5 single board computers (SBCs) but, I wanted to have a go at compiling it on my Kubunu Linux desktop PC. I found it straight forward to follow the instructions in the pihpsdr-install.pdf file and in no time at all I had the software compiled and running.

PiHPSDT running on Kubuntu Linux 22.04LTS — PiHPSDR running on Kubuntu Linux 22.04LTS

PiHPSDR is infinitely configurable and thus it feels like it has an infinite number of menus and options. Since the HL2 has two separate receivers, it’s possible to listen to two bands at the same time. This is the one feature I really missed more than anything with my FTDX10 so, I’m glad to have dual receive capability back once more!

Going through all the settings I realised that the A and B VFOs have individual settings. Initially I setup the software using just VFO A but, when I switched over to VFO B none of my settings were there. I then had the realisation that the settings apply only to the active VFO. I quickly went through all the settings again for VFO B and all was well.

In no time at all I was on the air with just 5w as my Xiegu amp hadn’t arrived. Not being perturbed I tuned up on the 15m band and started searching for stations. Interestingly it was CQWW SSB weekend and the band was full of contest stations. Working my way along the spectrum I found I was able to work quite a few stations with ease using my vertical and inverted-L antennas.

Contacts of note were VE3KG at 3406 Miles, VE3JM at 3382 Miles, RW9DX at 2380 Miles, KC1XX at 3331 Miles and N1DE at 3600 Miles. I also worked a bunch of European stations and had a great time giving away points with my little QRP rig.

Contests are a good time to try out new radios as all the big stations with good ears are on the bands and make the effort to get us QRP guys in their logs.

I have been extremely impressed with the receivers in the HL2 radio. It handles both strong and weak stations exceptionally well. PiHPSDR really does have brick-wall filtering and I was able to work the weaker stations right next to large contest stations with ease. At no time did the front-end of the receiver get overloaded.

Below is a short video clip of a conversation on the 80m band. The band was quite noisy however, with a reduction of the AGC gain and the 2700Hz filter it’s possible to remove almost all the noise.

Hermes Lite 2 SSB reception on the 80m Band

On CW the radio is a real delight. With the filtering and AGC gain control I am able to use extremely narrow receive filters without any ringing whatsoever. I would say that on CW the HL2 is as good as my FTDX10 when it comes to receiving even the weakest of stations.

I’m sure on paper the FTDX10 receiver has better numbers however, to the ear there really is no discernible difference.

Below is a short video clip of D4DX on CW on the 80m band. The band was noisy but, with the 100Hz filter enabled and clever use of the AGC Gain I was able to remove almost all the noise completely, reducing fatigue on the ears and making reception very easy even though there was some fairly deep QSB at times.

Receiving D4DX on CW on the 80m band using 100Hz filter and reduced AGC gain

A few days later my Xiegu XPA125B amplifier arrived. Unfortunately the amp didn’t come with the normal PTT lead that comes from the factory and is detailed in the user manual. For some bizarre reason this is a chargeable option when you buy the amp from Martin Lynch and Sons even though it is included from the factory.

This meant I had to make a lead which was a problem as I didn’t have one of the mini DIN plugs required for the connection to the amplifier. Jumping onto Amazon I ordered a packet of two and sat back and waited for their arrival.

A couple of days later the DIN plugs arrived and I quickly made up the necessary phono/RCA to mini DIN lead and got the amp operational.

The Xiegu XPA125B isn’t cheap but, it’s a really nice bit of kit. The neat little LCD display keeps you informed of power O/P, I/P and O/P SWR, voltage, current draw, temperature and band selected.

With just 0.7w of input from the HL2 I’m able to get a full 100w O/P from the amp. On the lower bands I have to reduce the O/P from the Hermes Lite 2 even further so that I don’t over drive the amp.

Being an avid Short Wave Listener (SWL) I wanted to see how the HL2 performed when listening to the big AM broadcast stations. To my surprise it makes an excellent SWL receiver with better AM demodulation than many of the more expensive radios. Having the option to select receive filters up to 16Khz wide I found I was able to get the best audio possible from many of the broadcast stations including Radio Caroline on 648Khz. It’s quite an improvement over the 12Khz maximum on the FTDX10.

Listening to AM Broadcast stations

What makes this project even more exciting is that both the hardware and software are from the OpenHardware/OpenSource world. The complete circuit diagram, PCB layout and information is available for all to download, something you don’t often see these days!

PiHPSDR is one of the nicest SDR applications I’ve seen in the Linux world and even comes with a 200 page downloadable user manual. Something you don’t see in many Opensource projects. The source code for the application is downloadable and you are able to make your own changes to it without restriction.

Overall I am really pleased with the Hermes Lite 2 SDR transceiver.
It has two excellent receivers, is infinitely configurable via the PiHPSDR software and performs extremely well under all conditions. Since getting the radio I haven’t even switched on the FTDX10.

More soon …

24 October 202431 October 2024

Wouxun KG UV-980PL Quad Band Radio

I recently decided to look into a 2m/70cm FM radio for the shack for use on the local 2m/70cm repeaters and was considering the offerings from Yaesu and Icom however, the Wouxun KG UV-980PL caught my eye as it is a quad band, full duplex radio. Not knowing much about Wouxun radios I had to do some research to get an idea of what it’s like. Generally the radio gets very good reviews and most mention the excellent build quality.

There are two versions of the 980P radio, the 980PL that offers 6/4/2m and 70cm bands and the 980P that offers 10/6/2m and 70cm. The 4m is a band I’ve been wanting to try for some time and the 980PL with it’s 4m band coverage became even more appealing.

Wouxun KG UV-980PL Quad Band FM Duplex Transceiver

I decided to take a trip down to Martin Lynch and Sons (MLANDS), a good 2 hours or more drive for me, so that I could get hands on with the radios that I had been looking at.

I invited Alan, G1SQB along for the ride and a day out playing with radios as he lives 3 miles away and we often chat on air.

Arriving at the store we grabbed a hot brew and set about playing with the great selection of radios on display.

I initially looked at the Icom IC-2730E, a dual band full duplex transceiver that has been around for about 10 years and has good reviews. As expected the build quality is excellent and very easy to use. I found I was soon able to set up memories etc via the front panel controls. The only draw back is that it isn’t supported by the CHIRP programming software that I use. Other than that it certainly meets all the requirements for a 2m/70cm FM transceiver

Icom Ic-2730E Duplex FM Transceiver — Icom IC-2730E FM Duplex Transceiver

Next I moved on to the offerings from Yaesu including the FTM-500DE 2m/70cm transceiver. The colour screen is very nice and the menu system very easy to use however, the price is getting on for close to double that of the other radios and it doesn’t really offer anything more that interests me since I’m only looking for an analog radio.

Yaesu FTM-500DR dual band FM Transceiver

Sadly there wasn’t a Wouxun UV-980PL out on display and so I had to persuade the salesman to get one out of stock for me to play with. Unpacking the radio I was surprised at how good the build quality is, it really is comparable to the other radios that I had been looking at.

The Wouxun menu system is fairly easy to use once you’ve looked at the manual and got to grips the abbreviations used. The big plus is that this radio is CHIRP compatible with an optional programming cable (£19) and so loading the memories with repeaters etc will be extremely easy.

The Wouxun has dual receivers built in with a quad-plexer so, you can transmit on one band whilst listening to another band on the other receiver. One thing to note is that the 1st receiver covers all the bands, 6/4/2m and 70cm however, the 2nd receiver only covers 2m and 70cm so, it’s not possible to receive 4m and 6m at the same time. The radio also only has one antenna connection on the rear, would had been great if it had one connector for each receiver.

The really good thing about the Wouxun UV-980PL is that it comes with everything you will need, apart from the programming cable!

After much tinkering I decided to purchase the Wouxun KG UV-980PL, a Diamond V2000 6/2m and 70cm antenna plus 20m of Hyperflex-13 coax cable and connectors.

In the box you’ll find two mounting options for the removable head. There is a short connecting cable for use when the head is mounted directly on the radio body and a 5m long connecting cable for mounting the head remotely. This is really useful as I wanted to mount the head on a mic boom arm so that it’s easily accessible and didn’t clutter the desk space in the shack.

M0AWS Shack — Wouxun KG UV-980PL head mounted on a Mic boom arm

Since the radio also comes with the mobile mount I’ve fixed the radio body on the wall behind the PC monitor out the way. This setup has proven to be extremely good as I can see what’s happening on the display at a glance and easily grab the mic if called.

Programming the radio memories is extremely quick and easy using CHIRP. I had the local repeaters and my AllStarLink node frequencies and offsets uploaded to the radio in no time at all and was soon on air.

Programming the memories on the Wouxun UV-980PL using CHIRP

The microphone that comes with the radio is extremely good. You can operate most of the controls on the radio directly from the mic with ease and it has a good feel in the hand. Audio reports have also been very good and there’s no need to change it.

I’ve not yet got the new Diamond V2000 antenna erected but, I’ve been using the radio with my homebrew 2m/70cm end fed vertical dipole and my 4m band end fed vertical dipole and am getting excellent results. I can access all the local repeaters using the lowest power output setting and only have to use the medium/high setting for the repeaters that are further afield.

On the 4m band the radio performs well and I’ve been surprised at the distances I’ve been able to cover even though my 4m antenna is only 6-7m above the ground currently.

A few days after I got the new Wouxun radio there was an ARISS event whereby a group of Girl Guides would be talking to Astronaut Sunita Williams aboard the ISS. This was a great opportunity to test the receive capability of the radio and so I setup ready for the pass. Using just my simple 2m/70cm end fed vertical dipole I got great reception as can be heard in the video below.

Overall I’m extremely pleased with the Wouxun KG UV-980PL quad band radio and considering it’s much cheaper than the offerings from the main radio manufacturers it’s well built and performs extremely well. If you’re looking for a simple, analog FM radio for 6/4/2m/70cms then you can’t beat it!

More soon …

6 October 2024

ISS Special Event contact with Astronaut Sunita Williams

A special event organised by the RSGB and Amateur Radio on the International Space Station (ARISS), in collaboration with the UK Space Agency, Girlguiding Surrey West and Brooklands Museum’s Innovation Academy programme took place today and I was fortunate enough to actually receive the signal from the ISS as it passed over Europe.

The contact with NASA astronaut Sunita Williams was also attended by The Duchess of Edinburgh who asked the first question via radio to the NASA astronaut.

Following this a number of girl guides posed questions which were very quickly answered as the ISS passed overhead.

Using my new Wouxun UV-980PL and simple end-fed vertical dipole I got a great signal from the ISS HAM radio station and was able to receive the ISS side of the conversation as the space station approached the N/W Coast of Spain until it eventually dropped below the horizon out of site nearing East Russia.

Below is a short video clip with audio showing the clarity of reception. The ISS peaked at an S9 signal, it was a perfect pass for the special event.

I’m hoping to put up a better antenna for 2/4/6m & 70cm in the next few days so that I can start joining the local nets on these bands and perhaps get contacts through a few more of the FM Low Earth Orbit (LEO) satellites.

I’ll also be writing a full article on the Wouxun KG UV-980PL in the very near future, so if this radio is of interest to you then watch this space.

More soon …