Forums > Sailing General

Hf radio antenna help.

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Created by oldboyracer > 9 months ago, 14 May 2018
oldboyracer
NSW, 292 posts
14 May 2018 11:39AM
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I wish to instal the hf radio that is currently in my car temporarily to my boat . The reason for this is to keep track of my 80 year old parents that think travelling remote desert areas of Australia is fun, while I head north. For 30 years they have been giving me heart attacks wondering where they are ( they have only had one each) . Registration is no issue and I won't be carrying marine bands as that is not allowed with a land registered hf radio ( who would have thought ? ) . So I have a Codan 9350 auto tune antenna that relies on a ground plane, the grounding plate on my boat has been painted for many years and I'm told that it would now be no good due to paint. Has any one used this aerial on there fibreglass boat. I have heard of the kiss ground plane system ,anyone using that to great effect . I'm open to suggestions ,I really don't want to install another grounding plate as they just collect lots of growth. It's a small 32 ft boat . Going to a marine radio won't help as you guessed it ,I can't have land based channels fitted lol .no I don't want to buy them and me a sat phone. Thanks in advance

lydia
1920 posts
14 May 2018 2:15PM
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HF set up is an art not a science and the ground plane is everything.
What type of boat and do you have keel bolts.
How long from tuner to set and tuner to keel.

oldboyracer
NSW, 292 posts
14 May 2018 5:15PM
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Manitou 32. No keel bolts. I know these aerials have been used on steel trawlers ,The original cables which I'm using are 3 metres long ,I was Hoping to avoid replacing the grounding plate. Was thinking about just dropping the earth strap into the ocean when I was due for a radio schedule to see if that would work, It's going back into the van when I get home.

lydia
1920 posts
14 May 2018 3:50PM
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got a pic of the antenna set up

Trek
NSW, 1183 posts
14 May 2018 6:24PM
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In the absence completely of a grounding plate HF radios can still work OK using the negative ground system of the boat. ie. The entire length of the negative wires from stern light to bow light and the engine block. If the auto tuner (ATU) is any good it can probably handle that as a ground plane. Another possibility is to use the safety rail as a ground plane. What you want is the biggest continuous piece of metal you can make. You could even run a length of solid copper wire from ground to stern and use that.

To try out the negative of the boat wiring as a ground plane run the ground of the ATU to battery negative with a thick copper wire. To try out the top wire of the safety rail as a ground plane run the ground of the ATU to the top wire and connect it well. Because its stainless steel its not so good but the ATU may tune it.

(BTW Im assuming you are using the back stay as the antenna)

If the radio has a power setting try low power first and dont touch anything while transmitting :-) Otherwise theres mobile phones :-)

oldboyracer
NSW, 292 posts
14 May 2018 9:09PM
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Thanks for the replies. The aerial I'm using is off of my car. The hf radio has the same channels as my parents, it's them I want to keep in touch with. They go where there is no phone service. The auto tune is part of the sealed aerial base. I may just have to experiment with a ground for it ,my first thought was just drop the earth strap in the water and see what happens. It's the same as this one.


Trek
NSW, 1183 posts
15 May 2018 3:25AM
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Sorry oldboy on my little phone screen i didnt catch that info. I have used that setup before. The ATU is roughly designed to use the metal mass of the car body as a ground plane. So something similar on boat would work. I would buy some heavy tinned dc cable and cable tie it from bow to stern on both sides of boat along the toe rail. Then connect both of those to the ground of the radio. Chances are that will work much better than dipping ground wire in sea. Let us know how you go.

oldboyracer
NSW, 292 posts
15 May 2018 7:52PM
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Thanks for the information,I will give it a go and let you know. I'm still 2 months away from sailing

santanasaga
NSW, 123 posts
16 May 2018 7:55PM
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I have a kiss ground plane and it works great with a backstay antenna. No idea of if it will work a terrestrial antennae...

oldboyracer
NSW, 292 posts
16 May 2018 8:11PM
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Yes I don't know either ,but I was wondering about the kiss ground plane.

Charriot
QLD, 880 posts
16 May 2018 8:45PM
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As Trek mentioned .... In the absence completely of a grounding plate HF radios can still work OK using the negative ground system of the boat. ....
absolutelly correct, there are other more important factors for HF communication.
The length of the antena wire..related to fregvency
Tuning the transmitter - aerial ,...if automatic than easy job, if manual ...you need " S " meter-HF field strength meter
also time of the day, even season.
I personally managed on 1.8 MHz / 160 m radioamater band nearly 1000km at night in winter with
5 watts transmitter and elevated 40 wire across back yard .

HaveFun
NSW, 201 posts
19 May 2018 5:27PM
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I don't quite understand why you would go to the trouble of setting up old HF technology that is iffy communication at best

Trek
NSW, 1183 posts
19 May 2018 6:01PM
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HF radio has the advantage its not dependent on any infrastructure, you dont have to pay for recharges or monthly accounts, and it always works. Pending the ionosphere.

Skype the internet communications company have it right, they have a big disclaimer on their boot screen something like "Skype is not a replacement for your telephone and cannot be used for emergency calls". They are a "hi-tech" company who know how unreliable "hi-tech" is !!

oldboyracer
NSW, 292 posts
19 May 2018 8:03PM
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I have been keeping in touch with my aging grey nomad parents for the last 30 years via hf radio. I used to have to do "cell calls" via the old hf network to find them. It was simple, make the call from your phone,tell them the area you THINK they may be in and wait for up to two days till they listen in to a sched and called you via the hf to your phone.....state of the art then. No phone coverage for most of their trips at that time. Fast forward and now dad has upgraded his hf radio,junior got his old one. Sat phones are great, but neither him or i wish to buy one at this stage. Yes mobile phones cover something like 90 % of the population, unfortunately that means you have to be mister 90% and keep to the cities, i look at their pics of previouse trips with no one around for miles and never understood, now i sail for 3 months of the year and understand. The best advise they ever gave me was " do whatever it takes but go, go now,dont look back, tomorow is to late, you dont know if you will have your health then." Its more for dad, he is not real well at the moment, and yes most of the time i Could use a phone but he enjoys talking on the hf, i think for him it means one of us is on an adventure. Sorry if i rambled on, some times its more than just about Communications



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"Hf radio antenna help." started by oldboyracer