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QMX at sea

 

I thought I'd post a description of my attempt at operating the QMX from a cruise ship in case anyone is interested.
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The XYL planned a cruise for spring break and I couldn't resist stuffing the QMX go kit in my backpack to bring along.? Actually, it wasn't as spontaneous as that. Since the ship was registered in Panama, I needed an IARP (which took a few months to get).? I also wrote the cruise line (Carnival) and obtained explicit permission to operate onboard.? Their policy has an exception that allows bringing ham radio equipment onboard but says nothing about operating.
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The antenna needed to be easy to deploy and safe for passersby.? We had an interior room so deploying from a balcony was not an option.? I ended up using a 40m-12m loaded telescoping whip (designed and kitted by Ken WA4MNT) and a homebrew magnetic mount.? It attached nicely to the top of one of the 6 foot metal posts at the stern.? The lone radial ran along the tops of the posts and was taped in place using masking tape.? Since it was not possible to get a perfect match in this configuration, I used an Emtech ZM-2 antenna tuner.? The QMX's SWR Tune feature made it pretty quick and easy to adjust the antenna and tuner.
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As the decks are crowded for most of the day, I chose to operate before sunrise.? And since the reciprocal agreement between the US and Mexico is somewhat ambiguous, I only operated when in international waters.? So, from the Pacific Ocean off the coast of Mexico, on 40m FT8, with 5W into a very low-efficiency antenna, I made contacts up and down the West coast of the US, as well as Vladivostok and all over Japan.? I tried CW (calling CQ and tail ending) for an hour on 20m but it was a bust with zero spots.? Among other things, the poor CW outcome may have resulted from having to keep the antenna in a lower position due to high winds.?
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If I ever have the chance to do this again, I would use a sturdier antenna.? When the winds were calm the telescoping whip worked remarkably well. But in higher winds, the thin metal bent and it was not possible to keep the antenna up.? A wire antenna would have been ideal but was a non-starter for me due to passenger safety concerns (perceived and actual).

Here is a snapshot of pskreporter:


We were in grid square DM10 at the time:


Operating position:


Antenna:


Same location in the daylight:


Thanks, Hans, for such a neat little radio that is easy to deploy just about anywhere.

73, Mike KK7ER
 

That’s awesome! We are going on Royal Caribbean in December. I think they are a hard no on ham radio but I need to investigate further.?
 

That's awesome Mike, thanks for sharing your story!

Since SOTA is already taken, we'll need to start BOTA (Boats On The Air)!?

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73
de Roy - KI0ER
Littleton, Colorado USA
 

That’s awesome?
I had worried about burning mine up with my ZM-2 so it must be hardier than I thought. I’ll want to try this when it comes so tell me more about the swr tune feature.?


Mark Hogan


On Sat, Apr 6, 2024 at 9:45?PM Mike KK7ER <groupio@...> wrote:
I thought I'd post a description of my attempt at operating the QMX from a cruise ship in case anyone is interested.
?
The XYL planned a cruise for spring break and I couldn't resist stuffing the QMX go kit in my backpack to bring along.? Actually, it wasn't as spontaneous as that. Since the ship was registered in Panama, I needed an IARP (which took a few months to get).? I also wrote the cruise line (Carnival) and obtained explicit permission to operate onboard.? Their policy has an exception that allows bringing ham radio equipment onboard but says nothing about operating.
?
The antenna needed to be easy to deploy and safe for passersby.? We had an interior room so deploying from a balcony was not an option.? I ended up using a 40m-12m loaded telescoping whip (designed and kitted by Ken WA4MNT) and a homebrew magnetic mount.? It attached nicely to the top of one of the 6 foot metal posts at the stern.? The lone radial ran along the tops of the posts and was taped in place using masking tape.? Since it was not possible to get a perfect match in this configuration, I used an Emtech ZM-2 antenna tuner.? The QMX's SWR Tune feature made it pretty quick and easy to adjust the antenna and tuner.
?
As the decks are crowded for most of the day, I chose to operate before sunrise.? And since the reciprocal agreement between the US and Mexico is somewhat ambiguous, I only operated when in international waters.? So, from the Pacific Ocean off the coast of Mexico, on 40m FT8, with 5W into a very low-efficiency antenna, I made contacts up and down the West coast of the US, as well as Vladivostok and all over Japan.? I tried CW (calling CQ and tail ending) for an hour on 20m but it was a bust with zero spots.? Among other things, the poor CW outcome may have resulted from having to keep the antenna in a lower position due to high winds.?
?
If I ever have the chance to do this again, I would use a sturdier antenna.? When the winds were calm the telescoping whip worked remarkably well. But in higher winds, the thin metal bent and it was not possible to keep the antenna up.? A wire antenna would have been ideal but was a non-starter for me due to passenger safety concerns (perceived and actual).

Here is a snapshot of pskreporter:


We were in grid square DM10 at the time:


Operating position:


Antenna:


Same location in the daylight:


Thanks, Hans, for such a neat little radio that is easy to deploy just about anywhere.

73, Mike KK7ER
 

Nice to know there are cruise ship companies that allow ham radio equipment. All companies I checked so far had them on their forbidden items list. Should I ever consider this form of vacation, I will choose a company allowing my radio equipment.
 

In TUNE? mode, the? ZM-2 presents a 2:1 max SWR. That shouldn't hurt the QMX.
 

Very cool; thanks for sharing! There's certainly something to the notion that sometimes you've just got to try and make Qs!
A suggestion for anyone who might be considering a cruise w/the possibility of high winds, perhaps you want to use an unloaded hamstick (specifically the MFJ-1600T) which is an 8' whip that you can tune (autotuner). You can compact it down to a 4' tall section and tends to be pretty hardy.

On Mon, Apr 8, 2024 at 7:21?AM Richard Barnich <k8bma.rick@...> wrote:
In TUNE? mode, the? ZM-2 presents a 2:1 max SWR. That shouldn't hurt the QMX.



--
ジェームズのメール
 

Hi Mark,

Before the trip, i wrote down the best ZM-2 settings and whip lengths (found using a nanoVNA) for each band.
The resonance is narrow and the environment can affect the resonant point a lot but this got me within the ballpark.
On the ship, I extended the whip and set the tuner to my previously optimal settings.
Then I set the QMX in SWR Tune mode where it transmits at lower power and displays constantly updated SWR.
This allows for quick SWR checks between adjustments.
With the ZM-2 in "tune mode" (presenting at most 2:1 SWR to the rig), I tweaked the ZM-2 to get the dimmest LED that I could.
Then I switched the ZM-2 to operating mode and adjusted the whip length in small increments.
In hindsight, there are probably better procedures, but this is what I did at the time.
It took very little time to get the antenna system to an acceptable VSWR.
The QMX SWR protection was of course enabled.

?73, Mike KK7ER
 

On Sun, Apr 7, 2024 at 04:00 PM, Roy - KI0ER wrote:

Since SOTA is already taken, we'll need to start BOTA (Boats On The Air)!?


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