SSB installion- any experts?

Carolwildbird

Carolwildbird

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We (we being me and my tame electrician) are currently installing my SSB.

I have a copper strap, which was clearly put in when Wild Bird was built, running from a keel bolt (lead keel) through the boat (mainlt glassed in) to the back lazarette locker. I understand that lead keels are good for grounding, so this should be fine.
We intend to put the ATU in the back locker connected to the strap.

Initial advice from Bob Smith (sailcom) was that we didn't need separately to connect the main transciever box to the copper strap (in fact he thought this may case some earth loops if we did)

The ICOM instructions suggest otherwise- the diagrammes indicate that we should also connect the transceiver box to the copper strap.... unfortunately the SSB expert at ICOM Uk is away till mid next week, so I can't discuss with him.

Any thoughts from any SSB experts (bearing in mind most of this is a very steep learning curve for me.... explain in simple words please!)
 
Right.. I am wading my way though the links.

I guess its not a matter of what grounding to use-- I think we have decided that the keel connected copper strip (thanks Bowman) will be the grounding system (or at least we'll start there). The question is what to connect to it.

Sailcom's advice was just to connect the ATU to the copper strip. This is what is shown in the basic diagram on your link "HF radio at sea"

diagramme.jpg


The ICOM diagrams show both the ATU and the main transciver
box connected- as so:

icomdiagramme.jpg


and the text reads

icomgrounding.jpg


what to follow?
 
Hmm..just revisited the "how Rob installed his" on the ropeantennas link- and he grounds both as per ICOM. but puts in a DC block between the radio and the grounding plate

And what's all this about counterpoise wire? ICOM don't mention that....

/forums/images/graemlins/confused.gif /forums/images/graemlins/confused.gif /forums/images/graemlins/confused.gif /forums/images/graemlins/confused.gif /forums/images/graemlins/confused.gif
 
Right we now gett slightly technical

Ground systems ?????????????

Basic answer Antenna (backstay etc) needs to push against ground, eg Keel bolts. engine through hulls etc Thats RF FLOW

All can be connected to the same grounding but with capacitors to stop DC current flow.

Having said all above I did connect all the kit to the the same ground system with no problems and have an excellent signal with no feedback.

As a HAM I have played with these issues for the last 30 years and there is still no correct answer, just try it and see.

Peter
Radio needs to be earthed with no RF, so dc current
 
[ QUOTE ]
.

As a HAM I have played with these issues for the last 30 years and there is still no correct answer, just try it and see.


[/ QUOTE ]

Agree entirely. Suck it and see.
 
They are bits of wire at certain lengths that make the ATU think its ground, they can be very good but are length specific..

Gets technical again, however if they are easy to install put them in its all a plus

Peter
 
Sorry am a bit slow reading and replying to mails.

The syintered plates are NO GOOD, waste of money and why put more holes in the hull,

Sea water is a great ground, but RF grounding goes straight though Grp, engine mounts, keel bolts etc

A sober (ha Ha) thought, big steel commercial vessels have a great signal, they all use a 23 foot vertical antenna (whip) but the ground is a steel boat, The antenna is not perfect but the ground is.

I could talk for hours and most HAMs do about antenna issues, there is never agreement.

Have faith and keep trying

Peter
 
err.. confused now.#
I didnt ask about alternative ground systems -we are going to use the copper strip bonded to the lead keel.

The simple question is.. connect the copper strip just to the atu (as per sailcom advice and the system outlined in HR radio at sea), or connect the copper strip to BOTH the atu and tranceiver box?
 
[ QUOTE ]
err.. confused now.#
I didnt ask about alternative ground systems -we are going to use the copper strip bonded to the lead keel.

[/ QUOTE ]

Great



[ QUOTE ]
The simple question is.. connect the copper strip just to the atu (as per sailcom advice and the system outlined in HR radio at sea), or connect the copper strip to BOTH the atu and tranceiver box?

[/ QUOTE ]


connect the copper strip just to the atu
 
In the absence of other information from Icom would it not be better to follow the instructions they supply with the set? That way there is no risk of any warranty issues in the future.

As is clear from the posts above you will get a differing answer from everyone who replies! /forums/images/graemlins/smile.gif

W.
 
My rf earth is connected both transiever and atu (ICOM). and works fine. Ensure its not connected to the dc earth. ( sometimes the keel is connected to the mast and / or the dc negative system for lightning protection ) My RF earth is just the guardwires and the aluminium toe rail. Works great.

Check everything for interference when recieving . especially the fridge, flourescent lights, laptop charger , torch battery chargers, engine alternator etc. on 198 khz, 693 khz, 4 , 8 and 12 mhz.
 
When I installed our Icom SSB I connected the dynaplate to the ATU via a copper strip. I then compared results with the main unit connected to the Dynaplate via a copper strip. I achieved better results with only the ATU connected.
 
[ QUOTE ]
In the absence of other information from Icom would it not be better to follow the instructions they supply with the set?

[/ QUOTE ]

It would be if there was, but there is no absence of other information!
 
OK... sound like, pragmatically, we should try it just with the ATU connected (cos we can do that with no extra work) and if that doest work well, add an extra connection from the copper strip to the transceiver box (slightly more hassle as the strip was glassed in when WB was built- exposed at the keel bolt and at the stern, but not in the middle).

Is there any risk in doing this? I can check with the icom expert towards the end of next week, but in the meantime....
 
[ QUOTE ]
[ QUOTE ]
In the absence of other information from Icom would it not be better to follow the instructions they supply with the set?

[/ QUOTE ]

It would be if there was, but there is no absence of other information!

[/ QUOTE ]

There is from the manufacture ICOM! The one who built and tested the set and the ones who will refuse a warranty claim if it all goes wrong.

W.
 
Does it not show on your diagram that the shield on the interconnect cable between the radio and the ATU is connected to earth at both ends, and therefore, the radio is by default already connected to the copper strip, albeit via the shield, so not a perfect RF path?

That's certainly the way the diagram shows things to be done for the M710 that I own..... and the route I am planning on following....

On top of this, the only other connection to ground is the -ve of the power supply to the radio, and thats not really a ground in RF terms, but a -ve connection to the battery.....
 
Now not having a clue about SSB Radios but looking at the ICOM diagram you posted Carol let me ask a question.
What looks like a multi pin hooded connector between the AT-141 and the main Transceiver unit also seems to have an extra 'tail' at both ends. The transceiver end seems to be connected to the Earth terminal and I'm guessing that the other end is maybe connecting to the AT-141 Earth Terminal.
If this is the case maybe it's to ensure that the earth connections in both cases are at the same potential.
I'm just thinking about it from an Audio installation where with multiple earth paths, we some times get ground loops and the dreaded 50Hz hum.
Again if you look at the ICOM diagram giving you a Ground system example the two units are connected by a common wire, then it is shown connecting to the earth.
Interesting to learn what the ICOM guy says when he comes back.
 
In theory terms it is the earth connection of the tuner that matters.This should be as short as possible because any long connection here carries current and so will radiate some power where you don't want it.

The radio itself will be grounded via coax shield system negative etc.

It is often desirable to not connect the tuner ground to the ocean by a DC connection as this can cause electrolysis problems. Often the ground connection of the tuner is actually via a large capacitor so it is ground for RF but not for DC. If it is not and you want isolation then a series of capacitors of about 1000pf and about 10 in parallel between the tuner and the sea will effectively ground the RF power.

good luck olewill
 
Hi are all of these plates no good. Alot of people use Dynaplates? is this an opinion or based on reasearch I hope to fit a SSB soon so any help on this subject will be good. Thanks
 
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