I’ve got a mast!

To be honest I’ve been so busy chasing QSO’s all over Europe and Eastern Europe the past few months I’ve been neglecting my pile of projects and housekeeping, so now that the weather is good it seemed like a good time to do something about getting my 30 meter 1/4 wave counterpoise antenna off of the top of the rotten fence post in the middle of my back garden and up onto something more becoming!

Back in March I started hatching a plan based on the advice of Mike (G0JMI) from Alton Antenna Arrays. Mike suggested trying http://www.aluminiumwarehouse.co.uk/ as a source of cheap aluminium tubes to build a sectional mast. The original plan was to use a 2.5m length of 40mm diameter 16swg tube and a 2.5m length of 44mm diameter 16swg slotted inside each other to give the overall 5m height. The 44mm section is fixed in position by driving a circular stake into the ground and slotting the aluminium over the stake.

It’s a very neat and cheap solution compared to the prices you pay for bespoke masts from radio suppliers! The only snag I had was the absence of any decent lawn or earth at the point I wanted to site the mast to anchor it. The joys of concrete! I looked at trying all sorts of anchoring solutions until I had the inevitable Gru “Lightbulb!” moment. (If that just passed over your head, watch Despicable Me and all will become clear). I’d got a perfectly good fence post set in a Metpost socket anchored in God knows how much concrete at the far corner of the garden behind the shed. There was potentially enough of the wood available to attach a square section tube to it.

I decided on a 5m 1.5″ x 1.5″ x 16swg tube costing a whole £16. The pisser was then having to pay the same again for delivery but you can’t have everything! A quick rummage around eBay provided a nice end cap to keep things dry inside, a few dog bone insulators and 100ft of Paracord. The local builders merchant came up with a cleat hook, eye bolt and some M6 coach screws.

Yesterday I nearly wet myself at the sight of a courier carrying the largest loo roll innard known to man up the drive. I was expecting a strip of aluminium not this thing!


Ironically it took more effort chopping the cardboard tube up to get it in the bin than putting the mast up.

Now naively, 5 meters doesn’t sound much inside my head, but when I held the tube up against the house it all came into perspective. Perhaps a shorter one would have done?

Now the whole idea of having a hobby is not to hack your neighbours off with it. Never has that been more true with amateur radio! There are huge great sections in the exam syllabus for the radio exams about EMC and interference and alongside that there’s the professionalism of the sport, which says wherever possible don’t go sticking a thing that looks like a 5 meter light sabre in your garden for fear of causing a bit of neighbourly angst! To coin a phrase “With great erections, comes comes great responsibility”. (I’m sure someone can correct that misquote for me!)

Liberal application of a hacksaw reduced the height to an item akin to a high level washing line, which is not an uncommon sight in the back gardens of the numerous back to back terrace runs in the local area.

Now the next hurdle to overcome was anchoring this thing down in a safe and secure manner. I genuinely didn’t want it to come crashing down in a storm on my neighbours let alone anyone else’s property!


The weapon of choice to overcome this hurdle was a coach screw, more than one to be honest. Anchoring it in both horizontal planes meant it was going nowhere! Seriously, this thing is solid which is very reassuring.

Strangely, when I did my exam one thing that stuck in my head working through the Advance! course material was the paragraph about rusty bolt rectification. I don’t know why it stuck in my noodle, but it did because I then got a question on it in my exam, which was a banker! Then, last month RadCom had an in depth article on metallurgy including corrosion, rusty bolt rectification again! Now with all that in mind, preventing galvanic corrosion between the aluminium mast, steel fixings and so forth was top of my list. A top tip from my man at CP Fastenings was to heat shrink everything and place either nylon washers or insulating tape between surface unions. Worth the 5 minutes to do it, as in the salty atmosphere of the south coast of England, things corrode quite nicely with little encouragement!

So with all that in place and a few holes drilled we were off. Now typically, none of the other bits I had ordered had arrived so overnight a temporary lashup was made which could be easily undone when all the final pieces were to hand. Despite the 16mph gusts of yesterday the temporary fitting hadn’t budged! Again, reassuring.

Today, everything else was waiting for me on the door mat when I got home. So in no less than 15 minutes, everything was in place and the 30 meter counterpoise antenna was fixed to it’s new home, looking no more imposing than a washing line. I’m more than happy as I now have the ability to experiment further. My trusty 728HFA limited space antenna is hidden beneath the eaves of the house and works a treat, but admittedly being able to swing it through 90 degrees and run it away from the house and all the electrical noise it contains would be an interesting experiment. That’s for another day.

In the meantime, I can enjoy the rest of the summer sunshine / pouring rain beneath my new washing line.



Monitoring the ATU power meter via webcam

The snag I’ve now got is that I want to monitor the ATU power meter which is fine if you’re sat next to the rig, but no use if I’m remote.

The easiest solution is to stick a camera in front of it and view the output over the VNC connection. I toyed with several ideas of how to do this, but at this point the simplest and cheapest is to use a conventional USB webcam and just have an open window to the output on the screen when using the radio.

I managed to get hold of an HD webcam relatively cheaply, picking the Hewlett-Packard HD 4310. People had commented that it only had a plastic lens, was generally too plasticy etc but at the end of the day it’s looking at an ATU so I wasn’t overly fussed


With a the application of a few sticky fixers and a strip of insulation tape the camera was anchored to the desk in the right place so hopefully it doesn’t get knocked or moved.


Unfortunately I’m still using the default software which comes with the camera which is bloated to the point of crazy with all sorts of rubbish for social media use. I’ll eventually install something like Yawcam (http://www.yawcam.com/index.php) as a server and stream the output to VLC which has a very nice minimal interface and does server streaming very well, but in the meantime I’ve got a visible power meter which can be viewed wherever the radio is accessed from.

Screenshot 2015-02-28 08.38.25

The next problem to overcome is the required manual interaction with the ATU when changing band. At the minute I’m happily sat on 20M playing PSK-31, with an SWR of 1:1 but I’m sat next to the radio. If I want to be anywhere else the issue comes as to how to tune the antenna. The obvious solution is to use an auto ATU such as an SGC SG-211 auto-ATU


I’m kicking myself as there was one on eBay a month or two ago and I let it go and no one bought it which is a bummer as now there’s none floating around. It would have been the ideal solution.

I like the Elecraft T1 but there’s still a need for interaction to kick it off into tune. Oh well, that’s a problem for another day!


Java update nukes Denkovi board

Just a word of warning. My system recently performed a Java update to v1.8 of the runtime environment. As a result, all of my lovely auto switching on power up and power down of the Denkovi board stopped.

After a bit of playing around with the Denkovi Command Line Tool, I found that it was generating this error which was flashing up too quick to read in the shell script pop ups within Windows. “Java version 1.8 is detected but version 1.7 is required” – helpful!

So, the only solution I could find in the absence of an update from Denkovi was to uninstall v 1.8 manually. On reboot, all is back to where it should be.

I’ve also added commands to power the ATU back light so things are clearer in lower light.

Resolving Softrock Ensemble RXTX transmission problems #3

After the past attempts to get the system working successfully there’s been a bit of a lull in activity due to Christmas and the pressures of modern day life!
By way of a recap, the theory of the fault finding and proving of this system has involved breaking down the radio to its component modules on the system diagram, checking the functionality in various transmission modes, then adding modules back in and repeating until hopefully a functional system is achieved.

Radio setup variations
So far the attempts to date have involved trying to get the SoftRock and HDSDR to transmit a clean CW signal. The test rig receiving this signal has been a Realistic DX-440 linked to a SoundBlaster Live 24 USB soundcard feeding into Fldigi running on my Dell Netbook.

A lot of time has been spent trying to fathom out why the received signal on the waterfall within Fldigi is about as straight as a banana and it was at this point I’d just about given up.
This time the test instrumentation and encyclopedic knowledge base came courtesy of Andy G7UHN, who gave up an afternoon of his time, for which I will always be in his debt.
Using Andy’s Elecraft K2 hooked to a Tigertronics Signalink feeding into Fldigi running on a netbook, the CW signal produced by HDSDR is clean and straight. The DX-440, as good as it was in principle is, is causing the bendy signal and all of the confusion!
Anyway, in a Top Gear style, moving on, the next step was to test a voice transmission from the SoftRock/HDSDR rig.

By adding a cheap microphone to the onboard Realtek soundcard microphone input an SSB audio test call was made and monitored on the K2 using a set of cans. After a little tweaking of levels, voice was received load and clear! Huge steps forward in all of 20 minutes!

Now the next step was to calibrate the RX and TX channels within HDSDR. Bearing in mind you get absolutely no help in HDSDR as to what this actually entails, other than a very bland dialogue box buried away in a sub menu, it transpired not to be as onerous as I’d thought.

Screenshot 2015-02-22 14.42.38

The K2 generates a very nice tune signal which was used as a reference. Checking the waterfall clearly showed a spurious signal at 10 kHz down frequency. By adjusting the amplitude and phase raw and fine sliders this was reduced to zero.
One down, one to go! The next head scratcher was what to test the SoftRock’s TX against. The advice from Guru Andy was to test against another SDR to give a comparable bandwidth of radio spectrum. But I don’t have a second SDR? Oh yes you do! My first foray into the world of radio was playing with RTL-SDR dongles and using one as an ADSB receiver to pick up the transponder broadcasts from passing aircraft as virtual radar.

Take said dongle, plug it into an HF upconverter courtesy of Nooelec and Robert’s your fathers’ brother!

Thankfully Andy had one in the boot of his car where it had been lurking since he’d been using it at work so there was a strong possibility this problem child may get sorted in one sitting!
With a laptop running SDR# and a jury rigged RTL-SDR / upconverter / every conceivable gender changer the pair of us possessed / dummy load strewn across the bench we were good to go.

Corrections used for the upconverter and dongle within SDR# (upconverter shift = -124,997,870, R820T = 136)

The answer to the next question wasn’t so obvious “How do you key the TX button in HDSDR with the calibration dialogue and slider adjustment screen open?” As I’ve said before, HDSDR really isn’t my favourite piece of software because it’s written possibly from the perspective of a software engineer rather than a radio operator and these weird little nuances can be a pain. Anyway, believe it or not, you can control the TX functionality of HDSDR with other menu windows open, which flies against every other Windows program I’ve ever used!

Again, gentle tweaking of the amplitude and phase raw and fine sliders within HDSDR resulted in a nice clean signal and waterfall on the SDR# test rig.

Remember, this isn’t about being anal when it comes to dotting the I’s and crossing the T’s. Your licence stipulates that “the licensee shall ensure that the emitted frequency of the apparatus comprised in the Radio Equipment is as stable and as free from Unwanted Emissions as the state of technical development for amateur radio reasonably permits.”

Apart from hacking off other amateurs with your poor quality splattery signal, having Ofcom banging on your door and inviting themselves in for tea and biscuits is never good form!

At this point, everything is working! It’d be very easy to start reaching for the Cubans and San Miguel at this point as victory is close and we have a fully functioning and proved SDR radio, in effect the left hand side of the system diagram.

Radio setup variations
The next step is to get Fldigi working with the radio so digimode transmissions can be sent and decoded.
Thankfully, no one had reached for the beer yet as the minute Fldigi was run, both the TX and RX signals reverted to a complete pile of mush on the waterfall in both Fldigi and HDSR. What the hell was going on?

Fldigi uses Virtual Audio Cable to pipe its feed to and from the radio. RX input is via VAC1 and TX output to HDSDR via VAC2. The settings on both were revisited over and over in my initial fault finding months ago with no effect and we spent a good 20 minutes of educated guessing as to what was going on before we gave up. VAC is a proven product used the world over by radio enthusiasts who have documented its use. Admittedly a lot of enthusiasts are still using Windows XP and a lot of the software in use was designed on that platform. Despite Microsoft’s cross platform compatibility modes and so forth, nothing is going to be 100% comparable on a brand new high end machine running Windows 7 x64 and a Windows XP machine from several years ago. Just consider the driver differences for starters.

With that in mind we switched the TX and RX piping to VB Audio Cable which markets itself as a fully functioning virtual audio cable solution. With two cables set up, one for input and one for output things were good to go and a test call made. Guess what? It only bloody well works!

Now at this stage you’ve got two grown men giggling like school girls and wondering if what’s just happened was a fluke of technology.
Test again, it works. Test again; it works, again, again, again. It works! Crystal clear CQ calls originating from Fldigi in PSK31 and being picked up on the K2 rig sat next to it on the bench.
This thing needs to be on a real antenna and talking to people!

With the ATU plugged in and a live antenna on the back of it, all that was needed was minor tweaking of the microphone gain and Windows audio levels to give a good 1W TX and 1.1 reflected power on the ATU’s power meter.

Time to do this for real! Thankfully at quarter to five in the afternoon there was a healthy number of amateurs chatting away on PSK31 and with a little bit of patience, someone eventually calls CQ and we’re in!

First contact on my SoftRock SDR rig was with Giovanni (IN3GNV) in the Dolomite region of Italy at 1711 hrs on Monday 16th February 2015, reporting a 599 signal.

What can I say?

Has it been a pain? – Yes it has.
Was I ready to launch the whole thing out the window? – Yes I was.
How much have I learnt? – More than I could ever imagine!

This has been one of the biggest and steepest learning curves of my life, which if it had worked first time when I took it out of the box, would never have been attempted let alone conquered.

Admittedly I could never have done it alone and my heartfelt thanks have got to go to Andy for his patience, insight, advice and support. Also, things wouldn’t have been possible without my sponsor (you know who you are!) There have also been a load of people on various forums who have offered advice in one form of another, but if nothing else the encouragement and the offer that “when you get there and are on air it’ll have been worth it.”

They’re not wrong!

Resolving Softrock Ensemble RXTX transmission problems #2


The first objective is to get the radio working to the point that when Tx is pressed in CW mode a clean and stable CW tone is transmitted.

I’m rapidly learning that with this SDR radio setup there is a strong need to have a conventional radio or a second radio on hand to check the signal that the rig is transmitting.

This leads to the proverbial chicken and egg situation, plus the potential financial considerations. Should I have bought a conventional rig and then thought about building an SDR? Now I’ve built an SDR I need a conventional rig available to test it against. It may have been easier and cheaper to build a 6 foot brick wall and paint a bullseye on it and just head butt it repeatedly!

Thankfully, a very generous Andy has leant me a Sangean 803A/Radio Shack DX-440 (http://www.eham.net/reviews/detail/2814) from his youth. It is a truly classic receiver, which unfortunately they don’t make any more and I wish I could lay my hands on one. It has the advantage of having a separate BFO which is needed for this exercise.

Using the DX-440 with my trusty Sound Blaster Live 24 and an old Dell Inspiron netbook I was gifted over New Year, I’ve got the means to test what’s coming out of the Softrock.

The netbook has been reinstalled with a copy of Linux Mint 17.1 Xfce 32-bit as the Windows 7 installation on it meant it took nearly 20 minutes to boot! Gotta love Microsoft! It now boots in just under 40 seconds and comes with a whole host of useful radio based applications thanks to the repositories available. Our old friend Fldigi is installed and ready to go!


It’s a simple setup which allows the spectrum to be examined easily.

The baseline settings on the radio PC are as follows –

Within the Windows sound settings ‘Recording’ Line In for the Asus Xonar DX audio device is set to 2ch 24bit 192kHz

Within the ‘Playback’ Speakers for the Asus Xonar DX audio device is set to 16bit 192kHz

Both are set to 100% volume at present. There is the potential to overdrive the radio which may be causing an issue but at the minute we’ll leave them as they are.

Within HDSDR Soundcard options –

RX Input (from Radio) – Xonar Line In

RX Output (to Speaker) – Realtek Speaker

TX Input (from microphone) – Line 2 VAC (I’m ignoring this at the moment as I haven’t plugged a microphone in and annoyingly you can’t select an audio device option when there’s no device plugged into it. There isn’t a non or not connected option, so you have to select something)

Within HDSDR Options –

TX Output (to Radio) – Xonar Speakers


Within HDSDR Options –

Options > Input Channel Mode for RX > I(Left) / Q (Right)

Options > Output Channel Mode for RX > AF to Left Channel only

The RX settings aren’t relevant at present as this a test of the Tx functionality


Within HDSDR TX Options – (only available when the program is running and you hit the TX button!)

Options > Input Channel Mode for TX > I(Left) / Q (Right) [No Mic!]

Options > Output Channel Mode for TX > not selectable but set at I(Left) / Q (Right)

Swap I and Q Channels for TX output > enabled

Now the logic of this test goes like this. Tune the DX-440 to 14087 kHz, tune HDSDR to 14088 kHz in CW and hit Tx with a dummy load attached

The CW signal which is produced is received on the DX-440 and appears in Fldigi on the waterfall.

Again after much fiddling and stupidity on my part we eventually got somewhere.

This is a snapshot sequence of keying on HDSDR

Screenshot 2015-01-17 16.10.04

Screenshot 2015-01-17 16.10.06

Screenshot 2015-01-17 16.13.25

On the DX-440/Fldigi setup this is what is received

Screenshot - 170115 - 12 59 03

Unplugging the cable between the sound card and the DX-440 and listening in a reasonable quality CW tone can be heard. After a bit of playing around, bearing in mind I possess zero Morse key skills, I was able to key out a few letters sufficient enough for Fldigi to accurately decode them.

But it’s no time to for high 5’s and cigars! Look closely at the received signal in Fldigi. It bends and then becomes linear! That said, there are no spurious signals around my CW signal.

This is as far as it goes at the moment as I’ve run out of time, but we’ve accomplished something! We’ve got a radio that transmits a CW tone sufficient for a receiver to detect and decode it.

As to the quality of the signal, that still needs work. I have concerns about possibly over driving the radio and I need to have a long look at the Output Channel Calibration for TX settings within HDSDR. The bent signal is almost as if there’s a lag somewhere. These things need to be looked at again in a methodical fashion but it’s progress!

Resolving Softrock Ensemble RXTX transmission problems #1

The title of this one says it all. There are problems with this Softrock based rig and unfortunately there are no simple “follow this guide” solutions out there to alleviate the problem quickly and simply.
From the research I’ve undertaken there’s a definite need for an understanding of this radio system from the ground up but I can safely say after the man hours invested in this to date, with no success on the transmission side, I could kill for a “do this and it will work” guide just to have the pleasure of seeing it work!

As such I plan to document this as clearly as possible with as much detail so that anyone else who finds themselves with this issue doesn’t have the same battle I’ve had!
That said there are a huge mountain of variables which will differ between individual setups but the main issue I’ve found with other articles on the Internet is the massive contradictions between them and the assumption of a knowledge level that unfortunately I don’t have and it will be a few more years before I do.

As such, what I publish is “what worked for me” and hopefully will help someone.

To put the problem into context before we move towards finding the solution, it may help to recap a few things for those of you joining the party late and to prevent you from having to read pages of previous posts.

The brief of my project is to build a software defined radio (SDR) based around a purpose built PC with a high end soundcard and a Softrock Ensemble RXTX.

The spec of the Radio PC is as follows –

Intel i5-4440 3.10GHz  processor
ASRock H81M-ITX motherboard with an Intel chipset and on board Realtek ALC892 audio
16GB memory and a solid state hard drive

Xonar DX soundcard with driver version

The PC is running Windows 7 Professional x64 SP1

Prebuilt Softrock Ensemble RXTX

The antenna setup and antenna tuning unit (ATU) don’t influence the problem I have with the setup at this time but are essential components to any rig.

I am utilising VAC virtual audio cable version and also have VB-Audio cables A&B version installed.

The PC is mute, in that all Windows sounds are disabled along with any audio enhancements that Windows or vendor drivers provide. Check all the available sub menus as some of these features aren’t obvious and you don’t want any more spanners being thrown into the works!

The objective is to use HDSDR with Fldigi for transmission (Tx) and reception (Rx) of digimodes.

Since construction the rig has been working perfectly for Rx purposes with both my favoured SDR program SDRConsole and HDSDR.

Unfortunately HDSDR is the only package which supports Tx along with rig control, a nice spectral display, waterfall and so forth.
If anyone ever enables Tx support in SDRConsole I’ll be jumping ship, but we’ve got to work with HDSDR at the moment!

To identify the problem there needs to be a fundamental understanding of what a SDR radio is and how it works compared to a conventional radio that’s attached to a computer.

The following system diagram helps put that into context.

Radio setup variations

I would strongly recommend a read of RadCom’s article in the January 2015 issue (volume 91 number 01) entitled “Getting started in… software defined radio (SDR)”  which really helps lay the foundations.

Naively I was hoping that this thing would work straight away but by the very nature of SDR in this guise there is so much more you need to have functioning correctly before the whole system becomes stable and reliable.

Hind sight is a very exact science! If I’d have bought a Yaesu 817, a Tigertronics SignaLink and a few cables and plugged them all together with a computer on the end running Fldigi I would have had a radio system running digimodes in about 15 minutes, something that a very helpful chap at Martin Lynch & Sons pointed out to me when I rang them last week to speak about conventional rigs.

The thing is I wouldn’t be able to have a remote hidden rig in the manner I want to achieve if I utilised conventional radio hardware. That said I’m now several months on without a fully functioning rig and if the world was my oyster…!

Just before Christmas my good friend Andy (G7UHN) lent me his time, his Elecraft K2 and Elecraft XG2 signal generator in exchange for copious cups of tea and chocolate biscuits, to help fine tune the rig prior to hitting the Tx key.

Despite calibrating the Softrock against the WWV time signals there was still a few Hz discrepancy in the system which is down to the ability of the human eye to read a graticule on a PC screen. That said I hadn’t done too badly but perfection is the name of the game and using a signal generator to provide the reference source pays dividends.

Learning points –

Changes to the Softrock’s configuration is via the application CFGSR which needs to be installed for the Softrock to function and is part of the PE0FKO driver package.
When you make changes to the crystal frequency for the Softrock the changes are written to the file ExtIO_Si570.dll which is saved within the folder C:\Program Files(x86)\CFGSR.

Any changes made here are not global in as much that HDSDR also needs a ExtIO_Si570.dll file within the directory C:\HDSDR. After calibrating CFGSR and being mightily impressed with the results in SDRConsole, when moving across to HDSDR there was a degree of head scratching as to why the calibration had been lost. As such, make sure all your copies of ExtIO_Si570.dll are the same.

With that all sorted, the long awaited TX button was pressed (while transmitting into a dummy load) within HDSDR.
Fldigi’s rig cat works very well and sending a PSK31 transmission was reflected in HDSDR but received very weakly on the Elecraft K2/Fldigi setup which was two foot away.
In addition the transmitted signal from the Softrock just didn’t look right. It was by no means clean and it wobbled around all over the place which was very odd.

The problem was initially suspected between HDSDR and Fldigi with the settings of the virtual audio cables (VACs).

This precipitated a lot of head scratching and Effing and Jeffing over the Christmas period where I tried altering sample rates on the virtual audio cables, within Windows and within HDSDR and Fldigi until I’d exhausted every conceivable combination all to no avail.

It’s at this point I was ready to launch the whole thing out the window but that’d be defeatist!
This rig will work, but conquering the issue preventing it from transmitting won’t be a 5 minute job.

I’ve read countless web articles, guides and so forth over the last few weeks trying to glean anything which could point to the source of the problem.

The guys at the Softrock40 forum and several site owners have been brilliant in answering my questions.
I’ve got to highlight the advice from Steve Arntz (KM5HT) and it’s around his suggestions that this problem solve is based.

The principle is reducing the radio system to its absolute basics and building upwards. At present the finished article doesn’t work and there are too many complications to allow the easy identification of the root cause.

As such, this is a phased approach problem solve where the blocks of the system diagram are “unplugged” and checked for functionality before being plugged back together –

1. Disregard any thoughts of Fldigi and digimode transmission on the Softrock/HDSDR side. This removes any potential issues around virtual audio cables and reduces the system to the “radio” component alone

2. Get the radio functioning and able to transmit a clean and stable CW signal

3. Add a microphone and achieve a clean and stable voice signal transmission

4. Add Fldigi to the system and achieve a clean and stable data mode signal transmission

New Year, New Project (well …)

Ok, so the end of 2014 saw a suspension of all things radio in the name of festivity! 2015 sees the recommencement of work but unfortunately we’ve taken a few steps backwards.

Firstly my uber cool Ulitmate3 QRSS beacon has stopped working, just because I put it in an enclosure. I have no idea why putting it in a box has killed it so it’s back to the drawing board on that one. In short the GPS module appears to have ceased functioning and the beacon is receiving a spurious signal from somewhere that it thinks is the sync pulse from the GPS module. So, it just sits there merrily transmitting in its mind, but in reality nothing is happening. Removing it from the enclosure doesn’t rectify the fault which suggests something has got broken wiring wise in the process.

Hans Summers has released an alternative GPS module which arrived over Xmas, so eventually I’ll rethink my plans. Primarily I’m keeping the power supply outside the enclosure to minimise any noise which is a shame as my little 5v/3.3v board was a fun build and slots perfectly in the PCB rails inside the case. The bonus is the new GPS module runs on 5v straight off of the motherboard so it simplifies matters significantly.

Anyway, the SDR radio issue rattles on. A lot of time and effort has been spent trying to get it working fully. Receive is perfect and I couldn’t be happier. However, Tx is another matter! I’m getting very messy Tx signals with a lot of splatter and tracking down what’s going on is proving harder than expected.

At the moment (with much gratefully received assistance) I’m paring back the radio to it’s absolute basics and looking to get a clean CW transmission, moving then to voice, then to data. Not as easy as it sounds strangely enough because HDSDR is proving a tricky customer to configure and work with.

When I get to a point of success I’ll post something useful for those who find themselves in a similar predicament. All I can say is Google isn’t your friend on this one as there is so much contradictory information out there. The Softrock40 forum have been extremely helpful, but there isn’t a one solution fits all cure to this problem.

In addition various bits of test kit have landed which need building that will help this endeavour. Again, when they play their part any useful data will be shared.