Length of Insulated Backstay for Ham Radio - Page 2

Sonosailor · 19-10-2009, 19:34

Sergy:

You asked about the "ground". Don't think of the ground for the tuner and/or radio as an electrical ground for electrical safety. The ham radio ground is the counterpoise against which the energy is dispelled from the antenna. You don't need contact with your keel, a large mass of metal, or a great conductor to the water. The important factor is a large metal surface area against which the signal can push towards the antenna. I have used metal tanks and even the total amount of lifeline as the ground satisfactorily. Now, especially since being told that getting my water and fuel tanks involved in the energy use is just not smart, I have simply bought 25 feet of that tinned woven copper belt that is sold at auto maintenance stores for the purposes of grounding. I connected it to the appropriate wire on the tuner and unwove it just under the floor boards, and kept it separate and insulated from all other electrical grounding - which normally includes the engines, spars, other electrical components and the negative terminal of your batteries. The thin strands of wire in the belt have tremendous surface area, and the tinning appears to slow down the corrosion. I have been told I have the best 20 metre signal in the Caribbean.

The counterpoise has nothing to do with the other electrical grounding, and has no need to be connected to it. I don't know if using the electrical grounding might be a problem, causing sparks, corrosion, or the like; but why mess with it if it isn't necessary?

VE9RUM

Sergy · 20-10-2009, 08:30

Thanks everyone for your valued advice, as stated earlier my first project is to re-rig the standing rigging. In preparation for the future SSB radio I wanted to see if I could kill 2 birds with one stone, so all this advice has enabled me to be more prepared. When it comes time to buy a radio, Tuner and hook up I certainly will consult with this forum for advice.
Seeing there are several savvy communication thech. Type here I wonder if I could impose one more question
At the top of the mast I have a small whip antenna about 1/8” dia. and 2 feet long, that is sitting on a round metal case 2 “ in dia. 2 ½”inch high. I do not know what this is and am wondering if I should change it when I have the mast off. It is about 30 years old. When using my VHF radio this summer on the west coast of Vancouver island I was not able to hear or reach Canadian coast Guard. So I suspect something is wrong any advise. I could reach other boats maybe 5 miles away and they could communicate with Coast Guard.
PS I could always here the weather stations?? But Coast GUARD COULD NOT HERE ME??
Is this called hijacking my original poast?

Wotname · 20-10-2009, 18:20

Sounds like it is your VHF antenna and the antenna itself could be OK after 30 years BUT I would be surprised if the coax cable and connectors are still OK. Unless you can properly test it (i.e. VSWR the antenna, measure the loss of the coax/connectors, confirm radiated RF power etc), just replace everything, using quality low loss, coax, connectors, antenna.

GordMay · 21-10-2009, 04:53

Quote:

Originally Posted by Wotname

Sounds like it is your VHF antenna and the antenna itself could be OK after 30 years BUT I would be surprised if the coax cable and connectors are still OK. Unless you can properly test it (i.e. VSWR the antenna, measure the loss of the coax/connectors, confirm radiated RF power etc), just replace everything, using [sic: high] quality, low loss, coax, connectors, antenna.

✓ Exactly.

19-10-2009, 19:34	#1
Sonosailor Registered User Join Date: Mar 2003 Location: Fredericton, NB, Canada in the summer and fall; Caribbean in winter and spring aboard Cat Tales. Boat: FP Tobago 35 - Cat Tales Posts: 356	Sergy: You asked about the "ground". Don't think of the ground for the tuner and/or radio as an electrical ground for electrical safety. The ham radio ground is the counterpoise against which the energy is dispelled from the antenna. You don't need contact with your keel, a large mass of metal, or a great conductor to the water. The important factor is a large metal surface area against which the signal can push towards the antenna. I have used metal tanks and even the total amount of lifeline as the ground satisfactorily. Now, especially since being told that getting my water and fuel tanks involved in the energy use is just not smart, I have simply bought 25 feet of that tinned woven copper belt that is sold at auto maintenance stores for the purposes of grounding. I connected it to the appropriate wire on the tuner and unwove it just under the floor boards, and kept it separate and insulated from all other electrical grounding - which normally includes the engines, spars, other electrical components and the negative terminal of your batteries. The thin strands of wire in the belt have tremendous surface area, and the tinning appears to slow down the corrosion. I have been told I have the best 20 metre signal in the Caribbean. The counterpoise has nothing to do with the other electrical grounding, and has no need to be connected to it. I don't know if using the electrical grounding might be a problem, causing sparks, corrosion, or the like; but why mess with it if it isn't necessary? VE9RUM Last edited by Sonosailor; 19-10-2009 at 19:39. Reason: clarity

20-10-2009, 18:20	#3
Wotname Registered User Join Date: Jan 2008 Location: Perth, Australia Boat: Van DeStat Super Dogger 31' Posts: 1,250	Sounds like it is your VHF antenna and the antenna itself could be OK after 30 years BUT I would be surprised if the coax cable and connectors are still OK. Unless you can properly test it (i.e. VSWR the antenna, measure the loss of the coax/connectors, confirm radiated RF power etc), just replace everything, using quality low loss, coax, connectors, antenna. __________________ All men dream: but not equally. Those who dream by night in the dusty recesses of their minds wake in the day to find it was vanity: but the dreamers of the day are dangereous men, for they may act their dreams with open eyes, to make it possible. T.E. Lawrence

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20-10-2009, 08:30	#2
Sergy Registered User Join Date: Feb 2008 Location: Vancouver Canada Boat: Cooper Maple Leaf 42 Posts: 64	Thanks everyone for your valued advice, as stated earlier my first project is to re-rig the standing rigging. In preparation for the future SSB radio I wanted to see if I could kill 2 birds with one stone, so all this advice has enabled me to be more prepared. When it comes time to buy a radio, Tuner and hook up I certainly will consult with this forum for advice. Seeing there are several savvy communication thech. Type here I wonder if I could impose one more question At the top of the mast I have a small whip antenna about 1/8” dia. and 2 feet long, that is sitting on a round metal case 2 “ in dia. 2 ½”inch high. I do not know what this is and am wondering if I should change it when I have the mast off. It is about 30 years old. When using my VHF radio this summer on the west coast of Vancouver island I was not able to hear or reach Canadian coast Guard. So I suspect something is wrong any advise. I could reach other boats maybe 5 miles away and they could communicate with Coast Guard. PS I could always here the weather stations?? But Coast GUARD COULD NOT HERE ME?? Is this called hijacking my original poast?