SSB aerial cable Mark II

[john_q]

Not wanting to hijack the existing thread on SSB aerials, so a new Post

Background

I have a steel boat and an ICOM 802 with DSC fitted to it.

The vessel has a negative floating DC supply (i.e. No DC current flowing through the hull).

I was having a problem with the earth connections on the 802 leaking current to the hull. (When you power off the control head on the 802, this DOES NOT disconnect the 12 volt supply to the 802 so it was leaking the whole time and I believe these caused issues with Zinc anodes and steel plates)

On the advise of Bob Smith – Sailcom Marine I have fitted a grounding isolation bridge between the ATU earth and the hull and disconnected the earth for the Black box, this has solved the problem.

The cable I am using for an earth on the ATU is a piece of alternator cable bolted to the steel hull.

The cable I am using for the aerial connection from the ATU to the backstay is also alternator cable.

I am running the NW Caribbean SSB net at the moment and everyone is telling me that I am putting out a very strong signal, however, on receive, I seem to be picking up a lot more noise than some other people, .i.e. they are right next to me and are able to pick up a station that to me is buried in the static (my settings are Clarity = 0, RF Gain = 9).

Questions
If I changed to Coax for the connection from the ATU aerial to the backstay, would this improve the receive quality?

And if the answer to the above is yes, exactly how would I earth the shield at one end?

Thanks

 

[funk-an-bord.de]

Questions
If I changed to Coax for the connection from the ATU aerial to the backstay, would this improve the receive quality?
And if the answer to the above is yes, exactly how would I earth the shield at one end?

No, this would provide a path for the HF to the Ground and reduce the transmitted power as well as the energy the back stay offers to the receiver.
Look for sources of noise on the ship or in the neighborhood.
And isolate the sources of noise step by step.

The cable I am using for the aerial connection from the ATU to the backstay is also alternator cable.

The cable is part of the antenna.
The isolation of a alternator cable is not sufficient to withstand the HF voltage of some kiloVolt
GTO15 is used,
Greetings, Wilhelm

 

[john_q]

The cable is part of the antenna.
The isolation of a alternator cable is not sufficient to withstand the HF voltage of some kiloVolt
GTO15 is used,
Greetings, Wilhelm

Wilhelm

Thanks for the information,

I am still a bit confused, If I replace the existing cable with GTO15 will this improve my receiving capability?

 

[funk-an-bord.de]

I give you a link to an old book from ICOM
http://funk-an-bord.de/downloads/func-startdown/83/
There feed cable to the antenna should have a high isolation provided by the cable isolation itself or from stay offs, air, etc.
to withstand the high voltage during transmission.
That the reasn for my recomendation to use a high voltage cable.
During reception there is a very very low voltage coming from the antenna to the transceiver.
The cable will not give you better results for reception.
Wilhelm