Using the standing rigging as antenna (part 3/3)

Today I took a day off so I could go to the Taste of Dublin Festival but in the morning I wanted to finish the installation of the cabling. So this was my starting point:

Pulling cable

Again I soldered an eye into the end and closed off the cable so no moisture would get in. I also cleaned the copper contacts and sanded the corrosion off everything and treasted the surfaces with some compound I ordered from the USA: No-oxid. That should hopefully keep the connection electrically conductive in a highly corrosive environment such as a boat.

cleaned up connections

By the time I finished this it was time to go to the festival to meet my friends and continue later in the afternoon.

[some expensive food tastings in great company later…]

Now I had the controller and coax cable to install (also temporarily) under the floorboards of the cabin to the table. I need to change that once I go sailing but for now the location of my equipment in that corner suits me.

under the floorboards

It was a great opportunity to do some vacuum cleaning in places that I normally don’t get to:

all these wires in the corner

And here you can see the controller for the antenna tuner and the grounding for the Yaesu rig attached:

it's working

The transmitter is set to 1.875MHz (the 160m amateur radio band) that I had never ever in my life been able to use before. The green LED on the controller box indicates that the antenna tuner was able to make the standing rigging resonant for this frequency. SUCCESS!

SWR test setup:

Test setup

Here are the SWR graphs generated by the Icom 705:

160m SWR 80m SWR 40m SWR 20m SWR 17m SWR This rig can’t tune the 15m band but the Yaesu has no problem. I don’t know why yet… 15m SWR Same for 12m: 12m SWR 10m is fine: 10m SWR

(addendum 10/9/2021: I have also noticed that in wet conditions that the Icom 705 can’t drive the antenna tuner to tune where the Yaesu FT-857D can tune it. Needs to be investigated.)

That evening I made my first ever (FT8) QSO on 160m with Guernsey GU8FBO!

In general the antenna is working much better compared to the ATAS-120 and the YouLoop for reception. It’s a great addition to the boat/shack. I’m happy I finally set it up.

Using the standing rigging as antenna (part 2/3)

Another good day in Dublin to do work outside, this time we need to empty the starboard lockers so I can lay the garden hose I prepared yesterday and also install the antenna tuner in the small cockpit locker. I didn’t take a picture of all my stuff on deck. As it was a Sunday afternoon and not many people were around, I decided not to crawl inside the aft cockpit locker on my own. I got in up to my shoulders but was afraid that I wouldn’t be able to get out on my own! The reason I needed to get in there is to drill 4 holes so I could mount the antenna tuner inside, see the photo below:

No way I crawl in here on m own

You may wonder why I wrapped the antenna tuner in aluminium foil but this article from PA9X recommends it. When I finalise the install I may put it in a metal enclosure but this will do for now.

The device is kept in place by the bucket that contains part of the anchor so while I’m not sailing it isn’t going anywhere. I can look for a short or flexible person next Spring to finalise the mounting.

I also needed to connect a wire to the backstay outside:

backstay antenna connection

I laid the 3 cables: the garden hose with the braided ground cable inside, a coax cable and the power+control cable all together through the centre of the boat, under the engine mounts into the cabin.

No photos because I was too tired and dirty to do this and I was racing against the clock: I was ready just before 20:00! Later in the week I will finalise the install.

Using the standing rigging as antenna (part 1/3)

This is a long story so I’m splitting it up in 3 parts.

So, I have had a few stories about antennas and although I have been making some FT8 contacts with the little sprit on the back of the boat, it is not the best antenna. If you look at my boat there is a long metal wire almost going to the top of the mast. Some boats use that with the aid of insulators to create an antenna. But these are quite expensive. In any case you’d need an antenna tuner to make the antenna work with your transmitter. However as I did some research, one boat owner didn’t bother with the insulators and discovered that a modern antenna tuner can tune the complete rigging! So when I got a discount on the CG-3000 antenna tuner at Wimo, I decided to jump on it and hopefully improve the antenna situation on the boat.

Now this was a couple of months ago and I didn’t have the energy to deal with installing it because the long Covid lockdown just didn’t motivate me very much.

One of the things that are important when using a semi-vertical antenna, is a ground-plane. I already had some 10m of tinned, braided copper wire that seems a decent alternative for a copper strip that is the advised way of connecting to a ground plane. The boat also has a copper plate in the middle of the hull with connectors on the inside that is not used for the grounding of the engine:

Hull ground plate

But to get there I needed to lay a cable from the starboard aft cockpit locker to the cabin. The spacing is there but I wanted to protect the braided cable from moisture and abrasion. Some garden water hose to the rescue! I used rg-8x coax as a mousing line on the marina to get it all in:

laying out cables on the berths

Soldering an eye on one end with a bit of heat shrink to protect it from moisture:

soldering an eye on one end

And finally stuffing the open end of the garden hose with CT1:

No water will get in

That should make sure no water is coming into the hose! This was a good point to stop for the day. Tomorrow part 2 when we actually lay the cable.

Software Defined Radio and Windows on a Mac

As part of my plan to make some of the radio amateur band more accessible to me on the boat I have bought an SDRPlay RSPDuo. I receive a lot of QRM on the 40m band on my boat in the evening and given the fact that I can’t move anywhere nor can I drastically change my antenna situation I’m working on a plan using something called diversity radio. But that I will discuss in another article once I get closer to achieving that goal.

First I wanted to use the fantastic SDRuno software that at the moment only runs on Windows. As I have given up on my principles of using only Mac software a while ago, I’d thought getting it to work with my copy of VMWare Fusion 10 should be a no-brainer. Well…

Hardware

A MacBook Pro 2015 with 16GB RAM and a 2.5 GHz Intel Core i7 running macOS 10.14.6. So plenty of power to share with Windows. I also have a Windows 10 Home licence (although its activation keeps complaining but I bought an official USB stick with Windows dammit!). I decided to give Windows 4GB RAM and 4 virtual processors.

VMWare Fusion 10

The first thing we have to understand that if you sample 10MHz of radio spectrum at 14 bits, we are talking about a lot of data that needs to be transferred from the device to your Mac and then to Windows. At least 133MB/s of continuous data transfer over a USB bus! SDRUno uses a cool feature of USB to help with that, it’s called i-synchronous transfers. I now the Mac can handle this since I connected it to a DAC for hifi audio and that worked fine when I still had access to hifi in the dark days before the boat. But that’s where it went wrong because USB support is not easy in a VM environment since VMWare announced full USB3 support for the latest version Fusion 12. So I noticed that I could switch to bulk transfer in SDRUno but that was not great. I noticed a less than stellar performance. SDRUno would complain that the USB device suddenly disappeared and multi-tasking between Mac and Windows caused this to happen frequently.

VirtualBox 6.1

Since I tried not to spend another amount of money to upgrade VMWare Fusion I tried VirtualBox. This was a terrible experience both the UI and the data transfer suffered from lots of lag and hick-ups as it only supported USB bulk transfer.

VMWare Fusion 11

On my Mac I still use macOS 10.14 since the later OS versions are taking more and more control away from you and a lot of ham radio software doesn’t work properly. Thus I tried Fusion 11 as that is the latest supported release for my setup. I contacted VMware and I could purchase a licence for 12 and downgrade it to 11 if I have to. So I tried it with the demo version. It did support i-synchronous transfers but again it was not stable enough. Lots of times SDRuno complained the USB device disappeared and whilst decoding DAB it would just crash.

VMWare Fusion 12

I managed to borrow an even more powerful MacBook Pro running macOS 15 and I put Fusion 12 on it. Tried SDRUno again and it worked. DAB decoding worked as well. So that looked promising. But when I went to do some Mac work whilst listening to a DAB transmission it would fail again. So I was running out of options bar one.

Parallels Desktop

For some reason I didn’t consider Parallels Desktop. Looking at the price it seemed similar to a Fusion upgrade so that wouldn’t stop me. What I liked is that as soon as I started it it started downloading Windows and installed it for me. With Fusion and VirtualBox you have to do all of that manually. The other good thing is that it can pass the discrete GPU to Windows as well which SDRUno can use. So from the get-go it worked fine. Listening to DAB and doing all kinds of stuff on the Mac worked reliably. Sometimes you can hear drop-outs but it doesn’t crash nor make the USB device disappear. The only issue is that if you Mac goes to sleep and wakes up again you’ll use your USB device and have to restart SDRUno. It would be great it they could dynamically reconnect. You can also use Coherence mode which allows you to mix Windows and Mac windows in the same session as shown in the screenshot below.

So with this setup and I have listened many hours to my RSPDuo and it is an amazing piece of kit. I hope to write some more articles about my experiences with this radio and its software. I have lots of ideas and thanks to COVID lots of time to work on it as well.

SDRUno on Mac

SSTV reception from the International Space Station

Today I took the afternoon off from work to test if I can receive some SSTV images from the ISS. One of the alumni of the Moscow Aviation Institute is part of the Russian crew. They were running some experiments for the SSTV transmission capability.

First I had to check whether it was possible for me to receive it given the passes the ISS is making over Ireland. I’m using some software on the iPhone for this: Satellite Tracker by Star Walk.

I did make a mistake because the original time slot of 1620-1740UTC was a bit too early, however there was a pass relatively close:

Low pass of ISS

So I just switched on my Yaesu FT-857D with the ATAS-120A antenna on the back of the deck rack and hooked it to my laptop and lo-and-behold!

With this the full image:

SSTV image 7/12

I left the receiver running, suddenly I heard the second image pop up, then the signal dropped and reappeared again, must have been some interesting propagation path on the 2m-band.

second image ISS location

But I did get a more skewed image (which makes sense given the Doppler shift that must be more pronounced now as I didn’t change the tuning frequency):

skewed image 8/12

But with some correction it came out improved:

Skew corrected

Note there were 12 images in total to receive but given the time I made available, I’m happy I got one and a half!

Hardening a Raspberry Pi and MegaDV DMR

As described in previous postings I had a nice little package for my DMR radio experiments. I did notice however that there was a lot of noise when the unit was broadcasting on 144.950MHz that caused me issues with my FT-857D when I was working the local community on 145.575MHz. You can see a spectrum here when the MegaDV was broadcasting (thanks to Ana EI/EA7KMA for the loan of the SDR-RTL):

SDR spectrum image

And in general the noise level on HF was also higher when I had the unit switched on. So I bought a little aluminium enclosure from Germany. I also discovered that the CPU temperature was always around 55ºC and wanted to reduce it a bit. After talking to Mike EI2DJ he was able to cut some pieces of aluminium together with some paste to transfer heat from an IC. (Thank you again Mike!)

Today I finally had some time to move the Pi into its new enclosure. First I drew the PCB on a piece of paper with the area on the bottom with one of the ICs that I wanted to cool down drawn in. The CPU is on top and needs a heatsink but the MegaDV board is right above it so that is a future project. This allowed me to find the optimum placement of the pieces of metal as shown below.

The first metal plate was easier to place since there was enough free space for any pins sticking out the PCB. A bit of research indicated that Loctite Superglue should be suitable to glue metal to metal. And I put the heat transfer compound in between:

First metal plate

The second metal place would be in contact with the IC. Placement here was somewhat more critical since there are a few SMD components around it that are almost the same height. I also glued this with lots of heat transfer compound:

Second metal plate

After making sure everything fits and the Raspberry Pi was still working(!), I put some of the compound on the IC:

IC with heat transfer compound

Then it was time to reassemble it:

PCB in casing

You can see there is good contact between the PCB and the impromptu heatsink:

Heatsink visible

Now it was time to drill the hole for the external VHF/UHF antenna. I do have all the tools on board: vice, drill and Dremel. (I made a small mistake here because the top of the case had to be rotated 180º but it works.)

Top of case in vice

Once the hole was large enough, the antenna was fitted. However the MegaDV board needed a washer to keep it in place on the GPIO bus otherwise it would get loose when you screw the antenna back in (it’s the white-ish bit in the top left).

Hole ready to be filled

Now it’s working again:

Working Pi and radio

It has been running for the last 6 hours and the CPU temperature hovers around 45º so that is 10º less compared to the old case. I do not notice it is transmitting at all on the FT-857D unless I tune to about 10 MHz of the transmission frequency. So all in all a great success! (Once I can borrow Ana’s SDR-RTL again, I can see what the spectrum looks like now, to be continued).

Handheld Antenna Analysis with NanoVNA

Using the NanoVNA antenna analyser I did some analysis on my handheld antennas using a sweep from 144-440MHz centred around 292MHz. I did perform a calibration using the provided online documentation before I started all this.

I also used the provided SMA-JJ RG316 coaxial cables to connect the antennas to the analyser. I used the

nanovna-saver
software on my Mac connected to the USB port to control the analyser.

AnyTone D878 High Gain rubber duckie

This is the standard antenna provided with the AnyTone D878 handheld transceiver.

S11 return loss 144 440

S11 Smith 144 430

S21 Gain 144 440

Reteviz RHD771

This is an antenna I’d bought thinking it would be a better antenna to use “in the field”.

S11 Return Loss144 440

S11 Smith 144 440

forgot to save the gain image

Baofeng UV-9R rubber duckie

Standard antenna that came with my Baofeng UV-9R handheld transceiver.

S11 Return Loss

S11 Smith

S21 Gain

Feedback

Either to the NDR Whatsapp group or through my QRZ email.

Update 8/12/2020: this article from AD5GG is a nice introduction to some of these graphs as they relate to antenna tuners.

DMR hotspot on VHF

A couple of months ago I bought a DMR hotspot with the assumption that it was able to work on the VHF band (since I’m not allowed to work on UHF on my boat). But it didn’t do it! So, even though supposedly the MMDVM board would support it, it was minuscule SMD soldering so I gave up to fix it.

Luckily I was able to get a dual-band system but it would not fit the case of the Raspberry Pi Zero. That computer was also rather underpowered and so I have upgraded to a Raspberry Pi Model 3 B+ at the same shop. It also has more full-size USB ports so I can connect it to other equipment much easier.

It is working fine:

DVMega board in action

And on a legal frequency:

pi-star screenshot

You can see I was chatting with Jan, PA3CJP in the Dutch Brandmeister Talk Group 204.

My first fax!

There is still a thing called fax that is being used on boats and ham radio. It is actually called weather fax and I got a licence for MultiMode this week to help me decode all kinds of interesting signals.

So just now I went to 4608.10kHz to Listen the the Northwood (GYA) UK weather fax transmission. And it works great!

Screenshot 2020 10 17 at 17 02 02

And here is the previous weather report for the Atlantic:

uk weather fax 2020 10 17

Oleander sail

Today was a good day: with a pleasant crew (Ana and Gil) we went for a sail on Oleander. As it was quite gusty we put the main sail on the third reef so to make sure things were very safe. With an inexperienced crew (and that includes myself because I don’t know the new main-sail yet) I don’t want to overpower the boat and get in potential trouble.

Unfortunately one crew member lost the winch handle while tightening the main sail and as it floats we had to do a man overboard procedure! We did get alongside it but didn’t have anything ready to scoop it up so I hope someone will be able to use it at some point in time.

It was a great sail and Ana even tried to confuse the local ham radio community by making a QSO on the Dublin repeater with her callsign EI/EA7KMA/MM 🤣

Thanks to my new AIS class B transponder I can actually see exactly what we have been doing via the MarineTracker iOS application:

We made it to our home port safely with everybody intact. A nice shower to get everything wet when we were cleaning up the boat just added a bit of zest to the good experience! 🌈

DMR Hotspot continued

This is the setup as shown in the photo:

  • AnyTone D-878
  • Pi-Star MMDVM (Raspberry Pi board with VHF/UHF transmitter) hotspot

I’ve know added Talk Groups to the hotspot so it broadcasts activity on those channels so my handheld will pick it up. Amazing stuff, all built by radio amateurs out of love for tinkering!

Handlheld and Hotspot

And now there is a lot more going on:

Hotspot Dashboard

DMR Hotspot arrived

My Pi-Star MMDVM Hotspot arrived and I have set it for my station. Once I’m on the boat I will change the frequency to 2m since I can’t be active on 70cm. I will write more about it in upcoming posts because I’m still finding my way around. In the screenshot you can see that I have a QSO with EI4GGB, Owen in county Westmeath.

Pi-Star Dashboard

Setting up APRS with an iPhone and an AnyTone D-878

Today I received my BTech APRS-K2 cable to connect my computer/mobile device to the AnyTone D-878UV so I can use the APRS mode on 2m.

First I labelled two channels (see EI7IG’s APRS Page):

  1. “APRS” on 144.800MHz
  2. “APRS Voice Alert” on the same frequency, but with a Squelch setting that is opened by a tone of 136.5Hz and it transmits that tone as well.

The first one I don’t make part of a scan list, the other I have. Here you see the detailed settings for it:

APRS Settings

And here the settings for the second one:

APRS Voice Alert Settings

Great! Now that the radio was happy, I decided to enable the Vox setting and connect the radio to my iPhone where I run aprs.fi for iOS. Receiving worked great but transmitting seemed to fail? Following the instructions to the letter, I had enabled the VOX feature. After a lot of fiddling, I was going back to the AnyTone CPS’ Optional Settings and I noticed (by accident) that the VOX was only enabled for the internal microphone. You need to enable it for the external microphone only. That way you can still use it for handheld use:

Vox Optional Settings

Now, using my Baofeng UV-9R I could hear the transmission. Not sure if it went anywhere, at this time there is not a lot of activity happening. To be continued…

EI4IQB

Thanks to COVID-19 and unemployment I have time to do things I have wanted to do for a long time!

Whilst I got the transceiver selected, shipped and installed, I managed to contact the Netherlands’ government telecommunications agency to send me my radio-amateur paperwork. Thanks to EU legislation my exam result from 1984 was valid for Ireland! My former housemate Anderson scanned it for me (because that is still my address, thanks Global!) and I managed to register it electronically with the Irish government’s telecommunications agency. After 1 day(!) I got some questions about my location (being the boat) and then I got a message that payment was received. I went to the website and I had become EI4IQB!

In the meantime I did get my ham radio equipment (a discontinued model with broadcast FM included, see an earlier post). And now I could finally start transmitting again!

I got very emotional when I was listening to ham radio operator QSOs because it had been a long time since I was able to listen to these and I have great memories of those times… 😃

EI4IQB

Let there be an antenna

The antenna I ordered for my transceiver was made for cars and trucks. The reason I bought this one was that I’d figured I could mount it on the rack at the back of the boat. So I designed a mounting plate and and thanks to a local sailor (thanks again Roger) with access to a laser cutter, it was created in no time whatsoever!

This is where the antenna sits now:

ATAS-120A mounted

mounting plate

You can also see the new NavTex antenna as well.

Ham radio preparations

I didn’t have an FM radio on board and it’s lockdown, what happens if the zombie war starts and my mobile phone is not working? How do I know what to do? What may still work? Something must be done! Can I get a radio on the boat with the lockdown and the marina closed? Where do I let them deliver it? I was looking for multi-function shortwave receivers but then I got a better idea…

A long time ago, in a country far away, there was a nerd who found a safe space in the ham radio club of his secondary school. It had the call sign PI1GOE and it was an amazing place to be. The stuff we were able to do without adult supervision most school children can only dream off (like cycling to school on a Saturday morning at 3 o’clock in the morning to meet a couple of other students so we could “work” the 80m and 40m bands where the propagation was the best at that hour, no teacher in sight.) Since we had no teacher with a radio-amateur licence I decided that I should get one (I was 15-16 years old). I got it and became PE1KOO. When I left the Netherlands to work in the USA I left my licence by the wayside but always wanted to reactivate my licence. In the last 3 years I managed to find the necessary paperwork but life was far too busy to do something about it.

So I will get a shortwave transceiver and put it on the boat. That way I can also use it for email when sailing and lots of other uses! After a lot of research I found the radio I wanted and an antenna to match it. And the company was willing to ship it to me and ask the delivery company to call me when they arrive at the marina…

(There was a problem with the phone number but fortunately the general manager was in on the time of delivery):

A huge package!

I unpacked it and rigged a temporary antenna:

FT-857D

It’s great! Almost back in business…