Shortwave Radio On My Sailboat

[SoonerSailor]

Originally Posted by Brian.D

Not to rain on anyone's parade, but don't ever get caught using an Amateur radio for Marine use, unless your boat is sinking and you are 700 miles off shore. I am sure you get my drift.

I don’t think you have to be in quite such dire straits, but it would certainly have to be related to safety at sea to not be considered an illegal transmission.

[CaptainJohn49]

I have a Flicka 20 and was wondering what would be a good ham radio for a small boat like mine. I have an amateur extra license and use a KX2 10 watt transceiver. I have not used this on the water yet. I have Dyneema rigging so I can’t use the backstays. I’d like to have a semi-permanent mounting and at least 100w. Any ideas?

CaptainJohn49

[wtmf]

out to sea, why does anyone need a license for safety?

[Jim Cate]

Originally Posted by wtmf

out to sea, why does anyone need a license for safety?

In a genuine emergency, you don't need a license. But at other times, if there were no rules and regulations the airwaves would be a shambles. Those of us who are regular users of the MF and HF bands are grateful that there are some guiding rules for their usage, even if it can be a pita to comply with them at times.

Jim N9GFT/VK4GFT/WDJ4598

[Paul Elliott]

Originally Posted by CaptainJohn49

I have a Flicka 20 and was wondering what would be a good ham radio for a small boat like mine. I have an amateur extra license and use a KX2 10 watt transceiver. I have not used this on the water yet. I have Dyneema rigging so I can’t use the backstays. I’d like to have a semi-permanent mounting and at least 100w. Any ideas?

CaptainJohn49

One of the fun things about QRP (10W power or less) is the challenge of making those contacts.

On a boat, where I just want to make the contact, send or receive the email, etc, I prefer to minimize the challenges and run a higher-power transmitter. You might consider the Icom 7200 or 7300 ham xceivers. These put out 100W and have a great USB computer interface for some of the modern digital modes (or for decoding broadcast WFAX). You will also need a good antenna tuner unless you plan on single-band operation. It's best to be able to operate on multiple bands.

Dyneema rigging is perfect for stringing a wire alongside. Perhaps secure it with zip-ties every few feet?

[CarinaPDX]

Perhaps a bit of historical perspective would be useful. 40 years ago marine shortwave radios cost thousands of dollars, but you could buy a small Atlas ham shortwave radio for $300. Needless to say cruisers preferred the ham radios, and all of the maritime nets were on the ham bands, so we all got our ham licenses. Shortcutters did buy ham radios without licenses and try to use the nets but were shut out pretty quickly - hams were terrified that the ham bands would turn into a circus like the Citizens Band, and the FCC might take away the valuable ham spectrum. Then during a period of cost cutting the FCC turned over policing the ham bands to the hams themselves, which hams have done enthusiastically. As the marine radios came down in price and the ham radios went up there was much less of an incentive to go with ham gear, and with that morse code exam scaring neophytes increasingly there was a move to marine gear. And then the complaints began that hams wouldn't let non-hams join the ham nets (no kidding - not going to risk the ham bands for scofflaws). These days there are good reasons for wanting both, and since morse is no longer required for a general license it is easier to do. But now we have a situation where some hams (don't raise your hand at an ARRL meeting) are using their ham gear illegally in the marine bands. Aside from the obvious illegality (fancy an $8k fine if caught?) it is a threat to amateur radio: if hams can't be trusted to obey the FCC rules commercial interests will use that against us to try and infringe on the ham bands (a constant battle in any event). Our bands are worth a lot of money and there are frequent attempts to wrench them away.

Bottom line: if you are a ham then please respect the rules so that others in the future will also be able to enjoy amateur radio.

'Nuff said,

Greg
KF7BW

[SoonerSailor]

Originally Posted by CaptainJohn49

I have a Flicka 20 and was wondering what would be a good ham radio for a small boat like mine. I have an amateur extra license and use a KX2 10 watt transceiver. I have not used this on the water yet. I have Dyneema rigging so I can’t use the backstays. I’d like to have a semi-permanent mounting and at least 100w. Any ideas?



CaptainJohn49

I put a small block at my masthead, and using a black Dacron halyard pull up a 1/16” diameter piece of stainless steel lifeline as an end fed antenna that is tied off at the pushpit and fed with the GTO-15 from the ATU. Works a treat, and tunes up fine on 80 thru 10 meters.

BTW I have a KX2 too, but not so much for the boat.

[Mekik]

Originally Posted by SoonerSailor

I put a small block at my masthead, and using a black Dacron halyard pull up a 1/16” diameter piece of stainless steel lifeline as an end fed antenna that is tied off at the pushpit and fed with the GTO-15 from the ATU. Works a treat, and tunes up fine on 80 thru 10 meters.

BTW I have a KX2 too, but not so much for the boat.

What length have you used SoonerSailor?
I will also use on my 36ft sailboat.

[SoonerSailor]

Originally Posted by Mekik

What length have you used SoonerSailor?
I will also use on my 36ft sailboat.

I don’t remember to tell the truth. The wire runs from about 4 feet from the masthead, to about 2 feet from the forward end of the stern pushpit rail. I assembled the SS cable using SS cable clamps securing a loop at each end, so I could adjust the length in case it would not tune up well on my bands of interest. As it happened, it worked well from the beginning. My mast is about 45 ft from deck level BTW.

[SoonerSailor]

The problem with relying on the precise length of my antenna is that its electrical length is going to vary in your boat due to differences in length of the GTO-15 from the ATU, and coupling to rigging and rails. You need to be prepared to adjust the length if necessary.

[Brian.D]

@Mekik, the two recommended lengths are 23' or 43'. Ideally you want the antenna to be λ/4 of the lowest frequency you want to use. i.e. 234/7.15=32.7'. However, we do not want the antenna to be λ/2 or a multiple of λ/2 on any frequency we use. Most tuners will not be able to handle such a high impedance. So given that the two recommended lengths are 23' and 43', 234/23=10.17MHz and 234/43=5.44MHz.

I use the same theory at home to run a random length antenna @35.5' and use an MFJ automatic tuner. At the feed of the antenna I use a 4:1 UNUN and a RF Choak Balun to suppress common mode currents back into the shack. I also use a home made KISS based on data provided by KA4WJA analysis of the KISS counterpoise
https://briandphoto.net/KISS-SSB.html

As an extra class holder I am sure you already knew the math. I put it in for those that want to add a HF antenna to their boat but aren't sure of length.

By the way, 23' is what most manufactures of automatic tuners say will work for 80M ~ 10M.

[Mekik]

Originally Posted by Brian.D

@Mekik, the two recommended lengths are 23' or 43'. Ideally you want the antenna to be λ/4 of the lowest frequency you want to use. i.e. 234/7.15=32.7'. However, we do not want the antenna to be λ/2 or a multiple of λ/2 on any frequency we use. Most tuners will not be able to handle such a high impedance. So given that the two recommended lengths are 23' and 43', 234/23=10.17MHz and 234/43=5.44MHz.

I use the same theory at home to run a random length antenna @35.5' and use an MFJ automatic tuner. At the feed of the antenna I use a 4:1 UNUN and a RF Choak Balun to suppress common mode currents back into the shack. I also use a home made KISS based on data provided by KA4WJA analysis of the KISS counterpoise
https://briandphoto.net/KISS-SSB.html

As an extra class holder I am sure you already knew the math. I put it in for those that want to add a HF antenna to their boat but aren't sure of length.

By the way, 23' is what most manufactures of automatic tuners say will work for 80M ~ 10M.

Thank you Brian.
Let me try 43' first. If it comes very near to Alu mast, then I will try 23'. I will use 9:1 un-un.
Thank you for recommendations.
Fair winds and net QSOs.

[SoonerSailor]

Originally Posted by Mekik

Thank you Brian.
Let me try 43' first. If it comes very near to Alu mast, then I will try 23'. I will use 9:1 un-un.
Thank you for recommendations.
Fair winds and net QSOs.

You will have to include length of GTO-15 from ATU as part of the antenna length. On top of that, interaction of the antenna with other parts on the boat will also have an effect, so be prepared to adjust the length if things don’t work out per the calculations. Using a length as long as possible is generally best, as long as it doesn’t turn out to be one of the “forbidden” lengths your ATU can’t deal with.

[Brian.D]

Just so you know, it does not have to be 43'. It can be any length that is not λ/2 on any frequency you want to use. My test is to divide the length by 468 and then add that value to itself. As long as the frequency does not fall within the a ham band I am good. i.e., my 35.5' antenna shows λ/2 and multiples as 13.18MHz, 26.37MHz, 39.55MHz and so on. The lowest frequency I can use is 6.59MHz (234/35.5). So don't just take my word for it. Let math be your friend. LOL

Soonersailor is correct and I forgot to mention the length of the GTO-15 from the tuner to the base of the antenna is part of the antenna.

[SoonerSailor]

Try it without any 9:1 or 4:1 unun first, unless you don’t have a wide range antenna match/tuner.