Author Archive
Planning some more /P and /A
June 10th, 2014 | 
Author: All too quickly and the holiday is over
Apart from the UKAC on the Tuesday night I didn't do anything else with the radio, I did have the HF antenna up but the trapped nerve in my back meant I was in a lot of discomfort after being out and about during the day and so rested and zonked out on painkillers rather than struggling to set up the rig.
I must sort out a proper portable station that I can just open it up and start operating, I am impressed with Charlie's M0PZT porta-pack frame idea being an excellent solution especially for back packing.
In the past the wife and I used to be keen walkers, tackling many of the peaks in Cumbria, Snowdonia, the Peak District and elsewhere. We completed the Coast-To-Coast Walk back in 1991 and The Cleveland Way the following year.
Sadly I am too overweight now to be a serious Summits On The Air (SOTA) operator but I plan on getting back to a reasonable level of fitness. As it happens if I'd been more prepared our walk of Latrigg last week could have been my first Wainwright On The Air (WOTA) activation.
Next month we are off to the Isle of Skye. We are staying in a self-catering cottage with plenty of room so rather than being /P portable I can be /A alternative and will be able to set up the rig in the cottage so can use it as and when I want.
I've already mentioned the holiday coincides with the 50MHz/6 Meter UKAC and am currently toying with the antenna choice, one advantage of being so far North is I won't need to rotate it as pointing it South South East should cover most of the UK. From the photographs of seen the cottage is reasonably elevated with clear views across Loch Bay in that direction. There are mountains ranges to contend with but who knows with propagation? I'll be in the rare IO67 locator square so might even have to contend with a pile up!
I will almost certainly operate as 2E0NRD rather than M6GTG for that week as using just 10W might be a bit optimistic.
I got somewhat excited last week when I received an email announcing the RSGB First 50MHz Contest results I was down in 35 place in the SF section but with a rosette next to my callsign? Wow I'd got an award! Pleased with myself I jumped on twitter to spread the news...
Perhaps I shouldn't have been quite as quick to brag as it appears I was the only Foundation Level entrant!
Still I managed 4 verified QSOs on what by all accounts was a very difficult contest, with low activity and poor conditions. In fact I almost missed the contest altogether and was only alerted to the contest by a tweet by Robert @G1ZJP and was late starting as I needed to get the antenna up. I actually made 5 QSOs but one was broken because I mistakenly put 59 in as the serial number.. Doh!
This weekend is the 2nd RSGB 144MHz Backpackers contest and the Practical Wireless 144MHz QRP Contest Unfortunately the FT857 is too powerful for the QRP contests as the limit is 3W but I could have a go at the Hill Toppers section in the RSGB contest which is limited to 10W and as luck would have it I am left to my own devices this weekend so might take a drive in the car..
Apart from the UKAC on the Tuesday night I didn't do anything else with the radio, I did have the HF antenna up but the trapped nerve in my back meant I was in a lot of discomfort after being out and about during the day and so rested and zonked out on painkillers rather than struggling to set up the rig.
I must sort out a proper portable station that I can just open it up and start operating, I am impressed with Charlie's M0PZT porta-pack frame idea being an excellent solution especially for back packing.
In the past the wife and I used to be keen walkers, tackling many of the peaks in Cumbria, Snowdonia, the Peak District and elsewhere. We completed the Coast-To-Coast Walk back in 1991 and The Cleveland Way the following year.
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| Dipping my boots at Robin Hood's Bay in 1991 at end of the Coast-To-Coast |
Sadly I am too overweight now to be a serious Summits On The Air (SOTA) operator but I plan on getting back to a reasonable level of fitness. As it happens if I'd been more prepared our walk of Latrigg last week could have been my first Wainwright On The Air (WOTA) activation.
Next month we are off to the Isle of Skye. We are staying in a self-catering cottage with plenty of room so rather than being /P portable I can be /A alternative and will be able to set up the rig in the cottage so can use it as and when I want.
I've already mentioned the holiday coincides with the 50MHz/6 Meter UKAC and am currently toying with the antenna choice, one advantage of being so far North is I won't need to rotate it as pointing it South South East should cover most of the UK. From the photographs of seen the cottage is reasonably elevated with clear views across Loch Bay in that direction. There are mountains ranges to contend with but who knows with propagation? I'll be in the rare IO67 locator square so might even have to contend with a pile up!
I will almost certainly operate as 2E0NRD rather than M6GTG for that week as using just 10W might be a bit optimistic.
 |
| IO67 Locator Square |
Gobsmacked.. pic.twitter.com/sGDI4jDh1W
— Andrew Garratt M6GTG (@nerdsville) June 7, 2014
Perhaps I shouldn't have been quite as quick to brag as it appears I was the only Foundation Level entrant!
Still I managed 4 verified QSOs on what by all accounts was a very difficult contest, with low activity and poor conditions. In fact I almost missed the contest altogether and was only alerted to the contest by a tweet by Robert @G1ZJP and was late starting as I needed to get the antenna up. I actually made 5 QSOs but one was broken because I mistakenly put 59 in as the serial number.. Doh!
This weekend is the 2nd RSGB 144MHz Backpackers contest and the Practical Wireless 144MHz QRP Contest Unfortunately the FT857 is too powerful for the QRP contests as the limit is 3W but I could have a go at the Hill Toppers section in the RSGB contest which is limited to 10W and as luck would have it I am left to my own devices this weekend so might take a drive in the car..
M6GTG/P The results are in!
Last nights 144MHz UKAC Contest gave me the opportunity to try operating portable for the first time. Caravanning in the Lake District just outside the town of Keswick I had spent the previous evening preparing (see earlier post) and after a day out walking I set up the station in the awning.
I hoisted the 3-Element Delta Beam to full height and waited for the appointed time. The campsite was very quiet but I still attracted some strange looks as people wandered past!
In the end I struggled only making 6 contacts, I searched and pounced initially and then called CQ for a time with no response. The caravan site has a strict no-noise policy after 22:30 so shutdown and packed up just before 22:00 Despite the low number of QSOs I wasn't disappointed, given my location and low power (10W) I was glad of any contacts.
Earlier in the day my wife and I took the dogs on a walk to the top of Latrigg which is just to the North of the campsite and is one of the lowest fells in the Lake District at 381m asl. From the summit we could clearly see the campsite below at just 218m. So perhaps not the best spot to be operating from, being surrounded on all sides by mountains.
Next month I am away to the Isle of Skye for the UKAC 6m contest, encouraged by the Delta Beam I might have a go at constructed one for then (if the wife agrees)
In the meantime I have got the magitenna up for HF but haven't used it yet after all I am here on holiday and have to spend time with the wife and dogs!
Just a correction in my earlier post about passing my intermediate I neglected to acknowledge the help of Nigel (M0CVO) and SKARS for the assessments and organising the exam.
I hoisted the 3-Element Delta Beam to full height and waited for the appointed time. The campsite was very quiet but I still attracted some strange looks as people wandered past!
In the end I struggled only making 6 contacts, I searched and pounced initially and then called CQ for a time with no response. The caravan site has a strict no-noise policy after 22:30 so shutdown and packed up just before 22:00 Despite the low number of QSOs I wasn't disappointed, given my location and low power (10W) I was glad of any contacts.
Earlier in the day my wife and I took the dogs on a walk to the top of Latrigg which is just to the North of the campsite and is one of the lowest fells in the Lake District at 381m asl. From the summit we could clearly see the campsite below at just 218m. So perhaps not the best spot to be operating from, being surrounded on all sides by mountains.
Next month I am away to the Isle of Skye for the UKAC 6m contest, encouraged by the Delta Beam I might have a go at constructed one for then (if the wife agrees)
In the meantime I have got the magitenna up for HF but haven't used it yet after all I am here on holiday and have to spend time with the wife and dogs!
Just a correction in my earlier post about passing my intermediate I neglected to acknowledge the help of Nigel (M0CVO) and SKARS for the assessments and organising the exam.
First time working portable
Have taken one further step up the amateur radio licensing ladder, passing the Intermediate exam and assessments. A big thank you to Grantham ARC and Alan and Keith for invigilating and congratulations to my fellow candidate Mark Orbell who also passed.
My new callsign is 2E0NRD
I am currently writing this blog entry while on holiday sitting in the caravan watching the sun rise over the Lake District. I have brought the rig along with a M0CVO magitenna for HF and not wanting to miss out on the 144MHz UKAC tonight have a Sandpiper 3-Element Delta Quad.
It has already caused some strange looks on the campsite while I built it up and tested it last night and I hope I won't have any RFI issues as caravans are often fitted with wideband TV amplifiers! Thankfully the site is currently very quiet as the school holidays have finished.
Initially was going to make a Moxon for 2m but I messed up my first attempt and ran out of time to make another so at the last minute ordered the Delta Quad from Sandpiper. It is a well built antenna I just had to cut the three loops and solder them up, the instructions were very clear. It is easily dismantled and seems ideal for portable work so is an investment for the future. I hope to use it during July's VHF NFD.
The antenna has an excellent VSWR match and when testing I clearly heard a cw/jt65 beacon around 144.480MHz which must have been GB3NGI on the Slieve Anorra Mountain in County Antrim, Northern Ireland (IO65VB)
I will be operating as M6GTG/P tonight as don't want to upset my UKAC scores and I am not really sure what to expect as surrounded by mountains in most directions here but should be fun. I might even rope in Boris to give me a hand
Last Tuesday (27 May) was the 50MHz UKAC. I had intended to do some operating over previous Bank Holiday weekend and with reports of Sporadic E propagation picking up on 6m I had put my homebrew Moxon back up on the pole with the new rotator. Unfortunately the operating was curtailed due to the discomfort I am currently suffering due to a trapped nerve in my back.
That weekend saw some horrendous weather and it rained heavily for several days, indeed it had rained most of Tuesday, checking the VSWR in the evening before the start of the contest I was shocked to see it had risen from 1:1.5 to nearly 1:3!
I knew the bad weather was forecast before putting the antenna up so had made sure all the coax connectors and the feedpoint were properly sealed with self amalgamating tape so was somewhat perplexed. In the end I decided what I thought the issue was, the moxon frame was untreated softwood and in the bad weather had become very wet and damp and suspect it was affecting the resonance.
Despite this I decided to carry on as I was only running 10W and had a productive few hours despite some local noise.
Anyway time to put the kettle on and I will post an update about how I get on tonight.
My new callsign is 2E0NRD
 |
| Current QTH |
I am currently writing this blog entry while on holiday sitting in the caravan watching the sun rise over the Lake District. I have brought the rig along with a M0CVO magitenna for HF and not wanting to miss out on the 144MHz UKAC tonight have a Sandpiper 3-Element Delta Quad.
It has already caused some strange looks on the campsite while I built it up and tested it last night and I hope I won't have any RFI issues as caravans are often fitted with wideband TV amplifiers! Thankfully the site is currently very quiet as the school holidays have finished.
 |
| Testing the Delta Quad last night |
Initially was going to make a Moxon for 2m but I messed up my first attempt and ran out of time to make another so at the last minute ordered the Delta Quad from Sandpiper. It is a well built antenna I just had to cut the three loops and solder them up, the instructions were very clear. It is easily dismantled and seems ideal for portable work so is an investment for the future. I hope to use it during July's VHF NFD.
The antenna has an excellent VSWR match and when testing I clearly heard a cw/jt65 beacon around 144.480MHz which must have been GB3NGI on the Slieve Anorra Mountain in County Antrim, Northern Ireland (IO65VB)
I will be operating as M6GTG/P tonight as don't want to upset my UKAC scores and I am not really sure what to expect as surrounded by mountains in most directions here but should be fun. I might even rope in Boris to give me a hand
 |
| Boris not looking too impressed |
Last Tuesday (27 May) was the 50MHz UKAC. I had intended to do some operating over previous Bank Holiday weekend and with reports of Sporadic E propagation picking up on 6m I had put my homebrew Moxon back up on the pole with the new rotator. Unfortunately the operating was curtailed due to the discomfort I am currently suffering due to a trapped nerve in my back.
That weekend saw some horrendous weather and it rained heavily for several days, indeed it had rained most of Tuesday, checking the VSWR in the evening before the start of the contest I was shocked to see it had risen from 1:1.5 to nearly 1:3!
I knew the bad weather was forecast before putting the antenna up so had made sure all the coax connectors and the feedpoint were properly sealed with self amalgamating tape so was somewhat perplexed. In the end I decided what I thought the issue was, the moxon frame was untreated softwood and in the bad weather had become very wet and damp and suspect it was affecting the resonance.
Despite this I decided to carry on as I was only running 10W and had a productive few hours despite some local noise.
I |
| 27 May 2014 - M6GTG 50MHz UKAC QSO Map |
Anyway time to put the kettle on and I will post an update about how I get on tonight.
HAB Talks
I was shocked when I realised it has been nearly two months since my last update. The pace of life really hasn’t let up and neither have the time pressures of work, however on with recent radio antics...
Last week I gave two talks and demonstrations at local radio societies on High Altitude Ballooning in the UK and how to track them.
The first was at South Kesteven ARS (SKARS) the club I am a member of. The second was at Spalding and District ARS (SDARS)
This was an updated version of the talk I gave last year at SKARS. Since then I have started work on my own tracker NERD-1. Sadly development has stalled and is still only at the prototype stage (NERDTEST) but I was able to use it to demonstrate reception and tracking using the UKHAS Habitat system spacenear.us/tracker
The SDARS venue had a projector and a decent WiFi Internet connection which allowed me to demonstrate how to set up DL-FLDIGI for a ground station and NERDTEST being received and both showing up on the map in real time.
My original PowerPoint presentation has been given a total makeover and I has included some videos of Felix Baumgartner, Dave Akerman’s Babbage Teddy Bear and wacky chef Heston Blumenthal's ‘Spud-in-space’ feature from his new television program.
To show a real tracker Steve Smith (G0TDJ) of Project Hab had been kind enough to loan me his VAYU-NTX unit.
I am not the most confident of people when it comes to public interaction and it was encouraging to see people genuinely interested in what I was talking about and keen to have a look and I have had some very nice feedback.
Giving these talks has spurred me to pull my finger out and get on with actually flying something and finishing the payload!
Another mothballed project is my Ultimate3 beacon kit, still being only a Foundation licence means I cannot use it to transmit but that may be about to change as tomorrow I am sitting my Intermediate exam which will allow me to properly experiment with transmitters. The exam was arranged through SKARS by Chairman Nigel Booth and the date came through a little sooner than I was expecting so perhaps not quite as prepared as I really should be, but with a decent electronics background and some quick revision it should be fine....
My operating has been largely limited to the UKAC VHF contests, setting aside a few hours per week is manageable and my results are gradually improving, even getting some complements on my operating.
Two weeks ago I was able to attend the local Dambusters Hamfest at Thorpe Camp and managed to pick up a decent rotator, this has proved invaluable for the UKAC as I don’t have to keep going outside the shack to turn the antenna.
Now if I hear someone calling CQ and can monitor a QSO to get the locator and the bearing a quick turn of the dial and I have a better chance. The program I use is BD_2004 from W1GHZ, running in console window it is a simple case of setting up your own locator and then entering other locators the bearing and distance are given.
As well as the weeknight UKAC there have been a couple of weekend VHF contests, I managed a couple of hours this weekend on the RSGB 144MHz May Contest and I had the best DX ever and nearly every QSO was in a new locator square!
I wasn’t able to spend more time on the contest as we took the dogs on a sponsored dog walk on Sunday in aid of the local hospice and on Saturday I attended the British Astronomical Association, Radio Astronomy Group General Meeting at the National Space Centre.
The notion of amateur Radio Astronomy is something that has fascinated me, up to now the only dabbling I have done has been with meteor detection using reflections from the Graves space radar (blog entry). This year some of the talks dealt with using RTL-SDR and Arduino/Raspberry PI in low-cost observation. Also at the meeting was a number of demonstrations and stands from other projects we I was able to garner a great deal of useful information.
Being able to detect ‘Hydrogen-Line’ emissions to map the Galactic plane using a FUNCube or RTL-SDR dongle is astonishing, not to mention low cost VLF receivers to detect Sudden Ionospheric Disturbances SIDs and magnetometers to measure the effect of the solar wind on the earth’s magnetic field!
It is all on the to do list, but it was a great day with some really fascinating talks and some exciting plans by the group. It was a shame I had to leave earlier than I wanted as I did miss some of the later presentations.
Anyway best get an early night!
Last week I gave two talks and demonstrations at local radio societies on High Altitude Ballooning in the UK and how to track them.
The first was at South Kesteven ARS (SKARS) the club I am a member of. The second was at Spalding and District ARS (SDARS)
This was an updated version of the talk I gave last year at SKARS. Since then I have started work on my own tracker NERD-1. Sadly development has stalled and is still only at the prototype stage (NERDTEST) but I was able to use it to demonstrate reception and tracking using the UKHAS Habitat system spacenear.us/tracker
The SDARS venue had a projector and a decent WiFi Internet connection which allowed me to demonstrate how to set up DL-FLDIGI for a ground station and NERDTEST being received and both showing up on the map in real time.
My original PowerPoint presentation has been given a total makeover and I has included some videos of Felix Baumgartner, Dave Akerman’s Babbage Teddy Bear and wacky chef Heston Blumenthal's ‘Spud-in-space’ feature from his new television program.
To show a real tracker Steve Smith (G0TDJ) of Project Hab had been kind enough to loan me his VAYU-NTX unit.
I am not the most confident of people when it comes to public interaction and it was encouraging to see people genuinely interested in what I was talking about and keen to have a look and I have had some very nice feedback.
Thanks @nerdsville for an excellent talk on High Altitude Balloons and telemetry, look forward to your launch. pic.twitter.com/H8AevMNQ13
— Spalding DARS (@SDARS) May 16, 2014
Excellent talk at Club tonight by @nerdsville on high altitude balloons and radio data. Andrew knows his subject and enthusiasm infectious.
— Jim Scott G0HGH (@photoimagery) May 16, 2014
Giving these talks has spurred me to pull my finger out and get on with actually flying something and finishing the payload!
Another mothballed project is my Ultimate3 beacon kit, still being only a Foundation licence means I cannot use it to transmit but that may be about to change as tomorrow I am sitting my Intermediate exam which will allow me to properly experiment with transmitters. The exam was arranged through SKARS by Chairman Nigel Booth and the date came through a little sooner than I was expecting so perhaps not quite as prepared as I really should be, but with a decent electronics background and some quick revision it should be fine....
My operating has been largely limited to the UKAC VHF contests, setting aside a few hours per week is manageable and my results are gradually improving, even getting some complements on my operating.
Two weeks ago I was able to attend the local Dambusters Hamfest at Thorpe Camp and managed to pick up a decent rotator, this has proved invaluable for the UKAC as I don’t have to keep going outside the shack to turn the antenna.
Now if I hear someone calling CQ and can monitor a QSO to get the locator and the bearing a quick turn of the dial and I have a better chance. The program I use is BD_2004 from W1GHZ, running in console window it is a simple case of setting up your own locator and then entering other locators the bearing and distance are given.
As well as the weeknight UKAC there have been a couple of weekend VHF contests, I managed a couple of hours this weekend on the RSGB 144MHz May Contest and I had the best DX ever and nearly every QSO was in a new locator square!
I wasn’t able to spend more time on the contest as we took the dogs on a sponsored dog walk on Sunday in aid of the local hospice and on Saturday I attended the British Astronomical Association, Radio Astronomy Group General Meeting at the National Space Centre.
The notion of amateur Radio Astronomy is something that has fascinated me, up to now the only dabbling I have done has been with meteor detection using reflections from the Graves space radar (blog entry). This year some of the talks dealt with using RTL-SDR and Arduino/Raspberry PI in low-cost observation. Also at the meeting was a number of demonstrations and stands from other projects we I was able to garner a great deal of useful information.
Being able to detect ‘Hydrogen-Line’ emissions to map the Galactic plane using a FUNCube or RTL-SDR dongle is astonishing, not to mention low cost VLF receivers to detect Sudden Ionospheric Disturbances SIDs and magnetometers to measure the effect of the solar wind on the earth’s magnetic field!
It is all on the to do list, but it was a great day with some really fascinating talks and some exciting plans by the group. It was a shame I had to leave earlier than I wanted as I did miss some of the later presentations.
Anyway best get an early night!
Been a busy boy
Been very busy with the day job and too busy playing radio so this post will be a bit of a catch up!
JT-65HF
I have been using my newly built datamode interface in anger.
As well as running WSPR on occasion I have also been active using JT65-HF.
JT65 is a communication mode developed by Joe Taylor, K1JT, (specification here) originally intended for amateur radio communication with extremely weak signals such as Earth-Moon-Earth (EME) contacts on VHF it has gained popularity on the short wave bands using JT65-HF an adaptation of the JT65A protocol.
Being restricted to 10W it is an attractive method of making contacts. The protocol includes error-correcting features that make it usable even when the signals are too weak to be heard or are being subject to interference.
There are several how-to guides available
Get On the Air with HF Digital (from the ARRL)
JT65-HF -- an 'Odd' but Fun Digital Mode (from eham.net)
A number of software packages support JT65, the most popular being JT65-HF originally developed by Joe, W6CQZ. Sadly Joe is no longer developing the software, but the last version released still works, and is available at http://sourceforge.net/projects/jt65-hf/
Thankfully the project was open source and Beat Oehrli, HB9HQX as developed his own version with the catchy title JT65-HF-HB9HQX-Edition, available at http://sourceforge.net/projects/jt65hfhb9hqxedi/ This is the version I have been using with great success, the colour coding and simple button pressing makes a QSO straight forward and the built in logging and exporting make uploading to QRZ, eQSL and HRDlog painless.
Whilst to a traditionalist amateur operator it is perhaps a little slow, remote and impersonal (each exchange occurs during alternate minutes) I really like it! One advantage is I can set up the radio in the shack with CAT control via HRD and then have QSOs while VNC'ing into the computer from the laptop whilst in front of the TV with the wife and the dogs! (Thanks Tim G4VXE for that suggestion!)
I have been active on the 10/20/30 and 40M bands over the past few weeks making contacts with Bulgaria, Canada, Denmark, Germany, Greece, Iceland, Kazakhstan, Poland, Russia, Serbia, Sweden, Thailand, Ukraine, USA and Venezuela.
Contesting 'DX' Headset and Interface
I have become hooked on the RSGB UKAC VHF contests, operating on a Tuesday evening on different frequencies (50MHz, 144MHz, 432MHz depending on which week of the month) Whilst my results are small-fry compared to the big guns I have been more than happy with my modest antenna set up and less than ideal location (previous blog posts)
I soon appreciated that using headphones rather than the speaker made life easier but I was still using the stock supplied hand microphone. Several times I have found it difficult to make myself understood and suspected that not only am I plagued by my 'Black Country' accent and poor enunciation but maybe the microphone wasn't quite cutting it.
Not able to afford or justify the purchase of a Heil headset just yet I took inspiration from Charlie M0PZT and his recommendation for a budget solution using a £10 computer headset from CPC (product AV21444).
On the Yaesu FT-857D the microphone connector is a 8-pin RJ45 socket which is behind the removable front panel with the lead coming out of one of a number of openings. Whilst the panel is easily removable I didn't want to keep removing it when switching between microphones, also re-purposing an obvious CAT5 network lead was problematic as they are often thicker than the openings.
A quick look at the supplied Yaesu MH-31 microphone revealed it can be unplugged, so what I needed was a interface box where I could plug in the headset and the microphone lead. This would also allow me to try different headsets in the future.
My solution as pictured above is quite simple, I won't include any pictures of the interior as it is a bit messy and not my best work! It is built from salvaged parts, including the box. The RJ45 socket came from an old network adapter, but beware some sockets are only 6 pin not the 8 as needed here. The headphone part of the headset is a simple connection to the rear socket on the FT-857D (the grey cable on the picture above)
Most microphones designed for computers use electret elements which require a bias voltage, this is quite simple as the Yaesu microphone connector supplies 5V, so a simple resistor (8.2K) will supply this, also by using a couple of different capacitors and a switch I can select a 'thin' higher frequency response (for DX work) or a more normal 'fatter' response. A circuit can be found on George Smart's webpage, the bias is simply applied to the tip of the microphone jack.
The box also has a PTT switch, this could have simply grounded the PTT line but I wanted to have a LED indication on the box and again I could have just wired a LED and resistor to 5V and to the PTT line so it would light when the switch was closed, pulling PTT to ground and completing the circuit. I opted to use a simple transistor open collector switch to add a little isolation.
The interface works well and I used it for the first time last night in the 50MHz UKAC with my homebrew MOXON antenna...
6M/50MHz MOXON
My first contest back in January was the 50MHz UKAC and as I blogged I made a solitary contact due to antenna issues, i.e I didn't really have one!
I missed the February contest so this month I really wanted to have a decent stab at it which meant building an antenna. I decided early on that a Moxon was probably the easiest to construct, so I downloaded the MoxGen program to calculate the element lengths.
Using 1mm diameter 'garden wire' for the driven element and reflector. I had various bits of flexible plastic pipe kicking about and decided to use them to construct an x-shaped spreader, unfortunately the pipe was obviously from different batches and as soon as it was tensioned by the wire it bent into all sorts of strange shapes due to the different elastic properties so I abandoned that design.
I had left the build to the last minute and needed a quick solution, so yesterday morning plan-B was to go an get some cheap timber from the local B&Q on the way to work and build a simple frame to wrap the wire round.
I impressed myself by completing the construction of the frame in the short time I had at lunchtime!
One thing I hadn't appreciated was just how big the final antenna was, it wasn't heavy just big! So last night an hour before the contest started I fitted the choke balun and coax to the terminal block. To be safe I removed the other antenna from the mast and hoisted her up.
Moment of truth, thankfully the VSWR was around 1.5:1 at 50.2MHz, rising to nearer 2:1 at the top end of the band. Not ideal but close enough. The VSWR measurements would suggest that the Moxon is a little bit long, interestingly some online Moxon calculators suggested dimensions for a slightly smaller Moxon than the downloaded Moxgen program did? Something to tweak/experiment with possibly using some thicker wire to increase the bandwidth.
50MHZ UKAC 25 March 2014
I was sorted! Moxon antenna up, contesting headset and interface plugged in and a quick scan up and down and I could clearly hear several stations testing and setting up. I poured myself a beer and soon the contest started.
I finished the night with just 14 QSOs, more would have been nice and it wasn't through lack of trying I could hear many more operators but simply couldn't make myself heard either because the antenna was in wrong direction or due to low power and getting lost in the pile ups to stronger stations.
I was not disappointed in fact I was quite happy with what my 10W, my new headset and home brewed antenna had achieved. The Moxon showed great promise and directional characteristics but for some reason just couldn't get south as the map indicates.
Out of interest I wondered what the line of slight view from my mast looked like so I strapped a camera on to the moxon this afternoon..
Need more height I think, especially if pointing South and a rotator would be nice!
Well that wraps it up for the moment.. 73
JT-65HF
I have been using my newly built datamode interface in anger.
As well as running WSPR on occasion I have also been active using JT65-HF.
JT65 is a communication mode developed by Joe Taylor, K1JT, (specification here) originally intended for amateur radio communication with extremely weak signals such as Earth-Moon-Earth (EME) contacts on VHF it has gained popularity on the short wave bands using JT65-HF an adaptation of the JT65A protocol.
Being restricted to 10W it is an attractive method of making contacts. The protocol includes error-correcting features that make it usable even when the signals are too weak to be heard or are being subject to interference.
There are several how-to guides available
Get On the Air with HF Digital (from the ARRL)
JT65-HF -- an 'Odd' but Fun Digital Mode (from eham.net)
A number of software packages support JT65, the most popular being JT65-HF originally developed by Joe, W6CQZ. Sadly Joe is no longer developing the software, but the last version released still works, and is available at http://sourceforge.net/projects/jt65-hf/
Thankfully the project was open source and Beat Oehrli, HB9HQX as developed his own version with the catchy title JT65-HF-HB9HQX-Edition, available at http://sourceforge.net/projects/jt65hfhb9hqxedi/ This is the version I have been using with great success, the colour coding and simple button pressing makes a QSO straight forward and the built in logging and exporting make uploading to QRZ, eQSL and HRDlog painless.
Whilst to a traditionalist amateur operator it is perhaps a little slow, remote and impersonal (each exchange occurs during alternate minutes) I really like it! One advantage is I can set up the radio in the shack with CAT control via HRD and then have QSOs while VNC'ing into the computer from the laptop whilst in front of the TV with the wife and the dogs! (Thanks Tim G4VXE for that suggestion!)
I have been active on the 10/20/30 and 40M bands over the past few weeks making contacts with Bulgaria, Canada, Denmark, Germany, Greece, Iceland, Kazakhstan, Poland, Russia, Serbia, Sweden, Thailand, Ukraine, USA and Venezuela.
Contesting 'DX' Headset and Interface
I have become hooked on the RSGB UKAC VHF contests, operating on a Tuesday evening on different frequencies (50MHz, 144MHz, 432MHz depending on which week of the month) Whilst my results are small-fry compared to the big guns I have been more than happy with my modest antenna set up and less than ideal location (previous blog posts)
I soon appreciated that using headphones rather than the speaker made life easier but I was still using the stock supplied hand microphone. Several times I have found it difficult to make myself understood and suspected that not only am I plagued by my 'Black Country' accent and poor enunciation but maybe the microphone wasn't quite cutting it.
Not able to afford or justify the purchase of a Heil headset just yet I took inspiration from Charlie M0PZT and his recommendation for a budget solution using a £10 computer headset from CPC (product AV21444).
On the Yaesu FT-857D the microphone connector is a 8-pin RJ45 socket which is behind the removable front panel with the lead coming out of one of a number of openings. Whilst the panel is easily removable I didn't want to keep removing it when switching between microphones, also re-purposing an obvious CAT5 network lead was problematic as they are often thicker than the openings.
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| The lead removed from MH-31, RJ45 on interface |
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| Mic lead connected and headset |
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| The budget 'dx' headset |
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| Yaesu FT-857D mic socket as view from front |
The box also has a PTT switch, this could have simply grounded the PTT line but I wanted to have a LED indication on the box and again I could have just wired a LED and resistor to 5V and to the PTT line so it would light when the switch was closed, pulling PTT to ground and completing the circuit. I opted to use a simple transistor open collector switch to add a little isolation.
The interface works well and I used it for the first time last night in the 50MHz UKAC with my homebrew MOXON antenna...
6M/50MHz MOXON
My first contest back in January was the 50MHz UKAC and as I blogged I made a solitary contact due to antenna issues, i.e I didn't really have one!
I missed the February contest so this month I really wanted to have a decent stab at it which meant building an antenna. I decided early on that a Moxon was probably the easiest to construct, so I downloaded the MoxGen program to calculate the element lengths.
Using 1mm diameter 'garden wire' for the driven element and reflector. I had various bits of flexible plastic pipe kicking about and decided to use them to construct an x-shaped spreader, unfortunately the pipe was obviously from different batches and as soon as it was tensioned by the wire it bent into all sorts of strange shapes due to the different elastic properties so I abandoned that design.
I had left the build to the last minute and needed a quick solution, so yesterday morning plan-B was to go an get some cheap timber from the local B&Q on the way to work and build a simple frame to wrap the wire round.
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| Moxon on garage floor |
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| Coax and common-mode choke, and sturdy support! |
One thing I hadn't appreciated was just how big the final antenna was, it wasn't heavy just big! So last night an hour before the contest started I fitted the choke balun and coax to the terminal block. To be safe I removed the other antenna from the mast and hoisted her up.
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| Up in the night sky |
Moment of truth, thankfully the VSWR was around 1.5:1 at 50.2MHz, rising to nearer 2:1 at the top end of the band. Not ideal but close enough. The VSWR measurements would suggest that the Moxon is a little bit long, interestingly some online Moxon calculators suggested dimensions for a slightly smaller Moxon than the downloaded Moxgen program did? Something to tweak/experiment with possibly using some thicker wire to increase the bandwidth.
50MHZ UKAC 25 March 2014
I was sorted! Moxon antenna up, contesting headset and interface plugged in and a quick scan up and down and I could clearly hear several stations testing and setting up. I poured myself a beer and soon the contest started.
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| Time between QSOs for a 'selfie' |
I was not disappointed in fact I was quite happy with what my 10W, my new headset and home brewed antenna had achieved. The Moxon showed great promise and directional characteristics but for some reason just couldn't get south as the map indicates.
Out of interest I wondered what the line of slight view from my mast looked like so I strapped a camera on to the moxon this afternoon..
Need more height I think, especially if pointing South and a rotator would be nice!
Well that wraps it up for the moment.. 73
Datamode Interface built
This weekend I finally got around to sorting out my digital/data mode interface for the Yaesu FT-857D.
To transmit and receive digital/data modes you need to connect the radio audio in/out to the computers sound card in/out, the computer then runs the necessary software to encode/decode the signals. I want to try out WSPR, PSK, JT65 and some SSTV for starters I have spent too long just receiving and decoding...
There are a number of inexpensive commercial interfaces available, but many of them use the same basic design originally intended for eQSO/Echolink operation. I nearly succumbed but I had built an eQSO interface many years ago when using PMR446 and had most of the parts to build another.
I nearly took the easy route and got a commercial one since connecting up some home built circuitry to a £20 hand held is slightly less daunting than plugging it into an expensive rig! My original interface has been modified and reused over the years and was a bit of a mess, but being brave I decided I could tidy it up and I couldn't really damage anything if I took my time... actually the truth was I discovered I didn't have the necessary optocoupler IC so couldn't build a new one just yet...
A simple internet search for digital/data mode interfaces will bring up a great deal of information, schematics and ideas for home brew solutions. The basics can be found here for example.
The simplest form of interface is just a simple direct lead with the transmitter operating in VOX mode. However levels can be a problem as the line/speaker output from a computer can be too high for a transmitters microphone input. Also connecting a radio to a computer directly can lead to problems with ground loops and interference.
The computer can be made to control the Push-To-Talk (PTT) on the transmitter using a serial port with the software controlling one of the handshake lines (RTS/DTR) Some data mode software support CAT to allow control of the PTT as well as tuning the transmitter, but the serial port method is more universal.
The preferred interface, and the one I had built isolates the computer from the radio by using two audio transformers and an optocoupler. There is no direct connection between the two devices so keeps interference to a minimum.
I could have used the microphone and speaker output on the radio, but the FT-857D has a convenient data connector on the back. This is a 6-pin DIN socket as used by older (PS/2) computer keyboards/mice. Note the diagram shown in the FT-857D manual (as below) is the view as you look at the socket.
The connector has two "data" outputs but they are simply fixed level audio outputs from the receiver. The one of interest for most modes is the 1200 baud output (the 9600 baud output is more akin to a discriminator tap and is only of use for FM packet) There is a data-in (TX-audio) and a PTT control line.
Like many people I initially thought I could cut a lead off a mouse/keyboard and repurpose it, however I discovered most only use four wires and they don't use the necessary pins! You might be lucky especially with older keyboards or alternatively if you have an old keyboard extender cable they usually have all six wires present. Alternatively the plugs are readily available from the likes of CPC/Farnell.
I had a hunt around in a junk box and located a suitable keyboard extender cable. I chopped off the useless end and metered out the pins to identify the appropriate wires. Remember when looking at the plug the pins are swapped left-to-right compared to the diagram which is the socket view.
Well here is the insides of the interface.. and as you can see I completely failed to tidy it up! Not my best work, but I did put it in a new box and I did tape up all those unused wires!
One annoying issue I had was the audio from the computer wasn't getting to the radio, it worked and scoped out okay when out the box, but in the box it stopped working. I suspected a bad solder joint and redid them all, but still showing the same intermittent issue. I did notice flexing the board slightly out the box cause the fault and soon located a track on the vero-board which appeared to have a hairline crack, I couldn't see anything obvious but a wire soldered along it cured the issue.
I soon had it connected up and fired up WSPR
It was straight forward setting up WSPR to use a combination of CAT for tuning and the RTS PTT control and soon had some encouraging results, in fact these are some of the spots of my 5W signal on 10m/20m and 30m, I was grinning from ear to ear!
I had simply set up the FT-857D for basic USB transmission, however it does have a dedicated DIG mode, the manual refers to setting it up for RTTY/PSK, I very briefly had a go with PSK31 and Digipan and was successfully decoding signals and put out a few CQ calls (again on 5w) but got no immediate response. However checking PSK Reporter later it seems I had been heard by VC3S, OH1FOG and ES1JA maximum distance was around 3260 miles
Looking forward to spending some more time experimenting with the data modes.
To transmit and receive digital/data modes you need to connect the radio audio in/out to the computers sound card in/out, the computer then runs the necessary software to encode/decode the signals. I want to try out WSPR, PSK, JT65 and some SSTV for starters I have spent too long just receiving and decoding...
There are a number of inexpensive commercial interfaces available, but many of them use the same basic design originally intended for eQSO/Echolink operation. I nearly succumbed but I had built an eQSO interface many years ago when using PMR446 and had most of the parts to build another.
I nearly took the easy route and got a commercial one since connecting up some home built circuitry to a £20 hand held is slightly less daunting than plugging it into an expensive rig! My original interface has been modified and reused over the years and was a bit of a mess, but being brave I decided I could tidy it up and I couldn't really damage anything if I took my time... actually the truth was I discovered I didn't have the necessary optocoupler IC so couldn't build a new one just yet...
A simple internet search for digital/data mode interfaces will bring up a great deal of information, schematics and ideas for home brew solutions. The basics can be found here for example.
The simplest form of interface is just a simple direct lead with the transmitter operating in VOX mode. However levels can be a problem as the line/speaker output from a computer can be too high for a transmitters microphone input. Also connecting a radio to a computer directly can lead to problems with ground loops and interference.
The computer can be made to control the Push-To-Talk (PTT) on the transmitter using a serial port with the software controlling one of the handshake lines (RTS/DTR) Some data mode software support CAT to allow control of the PTT as well as tuning the transmitter, but the serial port method is more universal.
The preferred interface, and the one I had built isolates the computer from the radio by using two audio transformers and an optocoupler. There is no direct connection between the two devices so keeps interference to a minimum.
I could have used the microphone and speaker output on the radio, but the FT-857D has a convenient data connector on the back. This is a 6-pin DIN socket as used by older (PS/2) computer keyboards/mice. Note the diagram shown in the FT-857D manual (as below) is the view as you look at the socket.
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| FT-857D Data connector as in the manual |
Like many people I initially thought I could cut a lead off a mouse/keyboard and repurpose it, however I discovered most only use four wires and they don't use the necessary pins! You might be lucky especially with older keyboards or alternatively if you have an old keyboard extender cable they usually have all six wires present. Alternatively the plugs are readily available from the likes of CPC/Farnell.
I had a hunt around in a junk box and located a suitable keyboard extender cable. I chopped off the useless end and metered out the pins to identify the appropriate wires. Remember when looking at the plug the pins are swapped left-to-right compared to the diagram which is the socket view.
Well here is the insides of the interface.. and as you can see I completely failed to tidy it up! Not my best work, but I did put it in a new box and I did tape up all those unused wires!
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| The messy internals of the interface |
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| It looks better with the lid on.. |
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| Computer, radio and interface |
It was straight forward setting up WSPR to use a combination of CAT for tuning and the RTS PTT control and soon had some encouraging results, in fact these are some of the spots of my 5W signal on 10m/20m and 30m, I was grinning from ear to ear!
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| 10M Spots |
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| 20M Spots |
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| 30M Spots |
Looking forward to spending some more time experimenting with the data modes.
Cheap GPS module
Several of the Arduino projects I have been experimenting with have used a GPS module to provide accurate time and/or location information and in the case of the QRSS/WSRP QRP beacon a highly accurate GPS derived 1 second pulse is used for frequency calibration. A number of people have enquired about the GPS module I am using.
Most GPS devices have a limit on the altitude they work at, normally 60,000 feet or less. This is a legacy of the now defunct CoCom (Coordinating Committee for Multilateral Export Controls) restrictions. For my HAB project this restriction needs to be disabled and the GPS must be switched into 'flight mode' In the HAB community the favoured devices are made by U-BLOX
Therefore when I was sourcing a GPS I had search specifically for a inexpensive device using a U-BLOX.
I soon found something called a GY-GPS6MV2, it appears to be a generic design and is readily available on eBay from suppliers in China, Hong Kong and Singapore and can be purchased at the moment for around than £10 (approx $15) including postage!
It is also available from domestic suppliers but often at a much more inflated price, but you don't have to wait several weeks for them to be delivered.
There are many other GPS modules available but this module seems to be one of the cheapest available. it is often listed as a NEO6MV2 GPS Module Aircraft Flight Controller.
The module consists of a small PCB 25mm x 35 mm size with a separate ceramic antenna connected by a small lead which is 25mm x 25mm in size. The Antenna is quite heavy and isn't suited to Pico HAB payloads but for other uses is more than satisfactory.
On the board is a small button-cell battery to provide backup to the GPS chip and a small EEPROM connected to the GPS chip which I believe can store configuration(s). I haven't used it myself just using the module in it's default set up at the moment. For a schematic click here
The board has four connectors VCC, GND, TX (Transmit) and RX (Receive) and can be powered by the 5V supply on Arduino boards since it has a small regulator to provide the 3.3V needed.
In most projects all that is required is data out of the GPS. The GPS TX (data out) being connected directly to the microcontrollers RX (data in) The (0V and 3.3V) level shift of the signal is compatible with the TTL input of the microcontroller.
The GPS by default will start up and output standard NMEA sentences at 9600 Baud, until GPS position lock is achieved the NMEA sentences won't have a long/lat location. The module also has an LED which will start flashing once a lock is achieved.
There is no direct connection for the highly accurate 1PPS (pulse per second) signal that can be used for frequency calibration, but the flashing LED is driven by pin 3 of the GPS module which is the 1PPS (pulse per second) signal required.
The 1PSS signal, like the TX is either 0V and 3.3V, in order to use it a small lead will need to be soldered onto the board, either directly onto Pin3 of the GPS chip, or alternatively on to the small current limiting resistor used by the LED, as indicated below.
Most GPS devices have a limit on the altitude they work at, normally 60,000 feet or less. This is a legacy of the now defunct CoCom (Coordinating Committee for Multilateral Export Controls) restrictions. For my HAB project this restriction needs to be disabled and the GPS must be switched into 'flight mode' In the HAB community the favoured devices are made by U-BLOX
Therefore when I was sourcing a GPS I had search specifically for a inexpensive device using a U-BLOX.
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| The GY-GPS6MV2 as supplied |
It is also available from domestic suppliers but often at a much more inflated price, but you don't have to wait several weeks for them to be delivered.
There are many other GPS modules available but this module seems to be one of the cheapest available. it is often listed as a NEO6MV2 GPS Module Aircraft Flight Controller.
The module consists of a small PCB 25mm x 35 mm size with a separate ceramic antenna connected by a small lead which is 25mm x 25mm in size. The Antenna is quite heavy and isn't suited to Pico HAB payloads but for other uses is more than satisfactory.
On the board is a small button-cell battery to provide backup to the GPS chip and a small EEPROM connected to the GPS chip which I believe can store configuration(s). I haven't used it myself just using the module in it's default set up at the moment. For a schematic click here
The board has four connectors VCC, GND, TX (Transmit) and RX (Receive) and can be powered by the 5V supply on Arduino boards since it has a small regulator to provide the 3.3V needed.
In most projects all that is required is data out of the GPS. The GPS TX (data out) being connected directly to the microcontrollers RX (data in) The (0V and 3.3V) level shift of the signal is compatible with the TTL input of the microcontroller.
The GPS by default will start up and output standard NMEA sentences at 9600 Baud, until GPS position lock is achieved the NMEA sentences won't have a long/lat location. The module also has an LED which will start flashing once a lock is achieved.
There is no direct connection for the highly accurate 1PPS (pulse per second) signal that can be used for frequency calibration, but the flashing LED is driven by pin 3 of the GPS module which is the 1PPS (pulse per second) signal required.
The 1PSS signal, like the TX is either 0V and 3.3V, in order to use it a small lead will need to be soldered onto the board, either directly onto Pin3 of the GPS chip, or alternatively on to the small current limiting resistor used by the LED, as indicated below.
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| Showing the GPS 1pps points |
