Second hand SSB's available?

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Amadis

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Second hand SSB\'s available?

Hi there,

I am looking to buy a SSB radio complete with all the 'bits' ATU, email capabilities etc.
However I am put off by the prices of new equipment. Are there companies selling second-hand / reconditioned units? Nothing fancy but reliable needed.

Cheers

Lily

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Re: Second hand SSB\'s available?

Bought my SSB through Ebay from a Radio Ham. Was advised against a S/H ATU as they can be unreliable dependant on where they were sited. An SSB and ATU was bought through these forums by another member a while back (inc ATU) and was OK.

There have been a number of posts on SSBs on the liveaboard forum.

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Re: Second hand SSB\'s available?

There's a good seller on eBay who sells brand new ATUs from ICOM for significantly less than retail. They ship in from Denmark.
Just bought one and installed it with my ICOM IC-706 and it works perfectly on a 9 metre backstay aerial. Grounding them is errrr....."Interesting" though!!!
If you want more detail etc, PM me.
Nick

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Re: Second hand SSB\'s available?

Which ATU and how much?

Cheapest grounding plates I have found (300 mm long versions) are just under £100, and for best results at 2182KHz I have been advised to have 2 of them

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Re: Second hand SSB\'s available?

Hi Nick-Pam,

Re the grounding (counterpoise) for your ATU. I don't know whether your Dehler has a bolted on cast iron keel or perhaps an encased one, but either way it doesn't really matter. If you run 75mm wide copper tape (it's about 5-6 thou thick) from the ground on your ATU to one of the keel bolts, you'll achieve a fantastic counterpoise. If you ally this to an insulated backstay aerial at least 11 metres long (or long whip aerial) you'll get superb transmission and reception responses. This method is much superior to the porous gold plated ground plate alternatives - and considerably cheaper!!

Incidentally, run the tape clear of the bilge floors if possible to minimise the chance of corrosion. All IMHO of course, but I, and many others I know use this tried and tested solution with excellent results.

Just a thought!

Good sailing!!

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Re: Second hand SSB\'s available?

I have an Icom IC M800 fitted to my boat, that I am unlikely to use, and may remove it. (I bought the boat in the winter and am hoping to launch her in the next few weeks when I have got her seaworthy)
I am not sure whether you can use it for emails, but if you are interested, please let me know.

Dave

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Ground plates

I fitted one in '99 when I fitted the SSB. In the 1st 3 times the boat was out of the water there were no evidences of any corrosion.

This spring,with the boat out of the water I had a considerable amount of work to do to rudder-fittings, keel and skeg to counter the effects of galvanic corrosion caused by, I suspect, the groundplate.

I would recommend avoiding the external groundplate and finding another method of ensuring a good RT earth.

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Re: Ground plates

Where the keel, rudder fittings, and skeg grounded to the plate, or were they isolated?

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Re: Ground plates

In many boats the ground plate will be connected to the other underwater metals back through the radio's DC negative if the boat's negative is bonded to ground (as is common eg to the engine, which is then often bonded to zincs and the other underwater metals) unless capacitors are used in grounding conductors of the antenna tuner or radio to break the DC path, or else if a radio with a DC negative isolated chassis is not used.

On the few side by side tests I have been able to conduct, the sintered plate type seem much inferior to more extensive ground systems. But possibly more effective than the common minimalist approach of using just a seacock as the ground.

John

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Re: Second hand SSB\'s available?

Hi Dave,

Would be interested to have more details about your M800, in terms of email capacities I think you need a separate modem for this to work.

Cheers
Lily

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Re: Ground plates

I am a bit concerned about accelerated galvanic action due to the SSB grounding plate. I was planning to use copper strip to ground via the keel bolts, I have a wooden boat with solid lead keel. I'm wondering if this will affect underwater fittings and prop etc.

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Re: Ground plates

Without more detail it is not possible to say.

But assuming that your boat's DC negative is grounded to your engine (usually through the fittings on it such as the alternater, temperature and oil pressure sensors, etc) and there is an electrical connection bonding your keel bolts directly or indirectly to the engine then using the keel as a ground for the radio will not make any difference from a galvanic corossion point of view.

If my assumption is not correct feel free to post or PM me the actual situation regarding whether your DC negative is connected to the engine (or to anything else with contact with the sea such as an anode) and whether the keel is electrically bonded to the engine or any other metals also connected to the DC negative.

John

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Re: Second hand SSB\'s available?

I sometimes wonder if this grounding plate business isn't a bit overdone - after all you just need a counter to let the ariel resonate against. My icom does sailmail and r/t with just an earth cable dunked in the oggin. When it's finished I take it out again!

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Re: Second hand SSB\'s available?

It is not overdone and any professional radio engineer will agree that is so. The matter is that even nothing will work to some extent - it really gets down to how good you want your radio's performance to be. If with a poor earth you get the performance you want, then that is fine, but it is no indication whatsoever that it will meet the requirements of a more demanding user.

It is possible for a system to work quite well with a 2 foot piece of wire as the antenna and a simple earth as long as propogation is kind, but it will not provide as reliable performance as a more comprehensive system.

One problem many casual radio users have is a yardstick to measure performance against - with a good radio installation you should be able to work, on a good day, similarly equipped (ie same power, antenna capability) around the world. I can work similarly equipped stations in the UK from here in New Zealand when propagation is at least average.

John

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Re: Second hand SSB\'s available?

Actually John it was a professional radio/radar engineer of 30 yrs experience who suggested it to me rather than making another hole in the hull, which I was unhappy about. He favoured using the boat's toerail but mine is wooden, so that was no go. I've never found conditions in which it is any worse than my rig at home, which is an icom 735 and an MFJ Super Hi-Q tuned loop with a 4ft copper rod as counterpoise. Of course it's not as sharp to tune! The system makes sense, after all, the wire in the water uses the entire North Sea as an earth, just as through hull plates are intended to do.

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Re: Second hand SSB\'s available?

Well I suspect that your "professional radio/radar engineer" was probably very technicianish because his advice was misinformed. In the end if you are making your own comparison with a a high Q (ie small) loop at home then I suspect anything would seem good as they are poorly performing antennas being of low efficiency. You will find all the literature will say the same.

In the end it all gets down to what one is satisfied with, but if one is only satisfied with a competent system then a significant ground is required. Your piece of wire you claim to use the entire North Sea, actually, it like anything else in the earth or water uses the whole of the earth as a groundplane and that would be so even if you used a 100mm long piece of wire, it is the degree of coupling that is important.

I suspect that I am on a wasteful journey here, so as long as you are happy with your own installation that is fine but your advice to others is uninformed and not correct.

John

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Re: Second hand SSB\'s available?

Hi Jerry

Which was exactly what I have just spent the weekend doing!!!!!!!!!!!
Well it was blowing a hoolie in Plymouth, so I let sleeping errmmmm yachts lie!!
I'd installed the radio on a previous trip down, so it was aerial weekend.

I think my isolated backstay section is a little over 9 metres - didn't actually measure it - whatever it is, the AH4 tunes it to perfection now and I worked about 60 or 70 stations on 80 metres around midnight on Saturday, all of whom said the signal was massive...so that is good enough for me...
Hooray for bolted on keels!!


Didn't think to keep the copper ribbon clear of the bottom, so that will be a "modifications" job next time I am down.....good idea that - thanks

Nick

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