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Old November 27th 04, 10:16 PM
James
 
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Bill Turner wrote:
On Sat, 27 Nov 2004 11:51:01 -0500, James wrote:


Ever been aboard an ocean going sail boat when the waves hit 5 meters
and the wind is howling like a freight train? If not you can't imagine
the fury. I've been there. It's exhilirating but not easy to endure. In
fact it's damned hard work. That is NOT the time to be playing with
knobs and switches trying to tune for a particular band.



__________________________________________________ _______

Your point is well taken, but this is also NOT the time for equipment
failure. If that nifty tuner gets dunked with a dollop of salt water,
you are dead, RF wise. The KISS principle is your friend.

Anyone who can do a sail change or heave to in 5 meter waves can clip or
unclip a jumper, or better yet, will have the jumper set beforehand.

To each his own.

--
Bill W6WRT




Thanks for the words of wisdom Bill.

In fact I made a point of purchasing a tuner that comes in a water tight
(read that water PROOF according to the manfacturer) case. It's high
up mounted in a lazerette that "theoretically" stays dry. The ground and
antenna stud are both 316 Stainless (highly corrosion resistant and
intended for use in salt air). Furthermore, the electrical connection
between antenna stud and wire is soldered, crimped, and then heat shrunk
with adhesive lined shrink. Instead of using high tension wire for the
antenna connection to the backstay wire, I used tinned copper heavy
gauge insulated electrical wire. The environment that I live in is so
corrosive that, believe it or not I had to strip back the jacket to
expose the tinned copper wire, and then seal the cut edge of the jacket
to prevent salt water ingress between jacket and wire. If that isn't
done even tinned copper wire will corrode. Salt water will creep under
the jacket and corrosion will occur for a few feet distance from the
stripped jacket.

All connections (RF, power and control) between tuner and radio are made
with crimp and solder, then sealed with liquid electrical tape, then
adhesive lined heat shrink. I bought really big insulators to go at both
ends of the wire antenna too. Salt water is conductive and the larger
insulator with heavy ribbing will hopefully reduce the surface coating
of salty water to a level that precludes conductivity. Hopefully. the
copper wire I ran up the mast is on it's own pulley (well it will be
when I find time to go up the mast) and is already a lovely shade of
green. I have a spare, and hope this one lasts a year before needing
replacement.

Even so, I expect to have to service the connections about once a year
or so.

And you thought putting a beam on a tower was hard! Just thought you'd
find the lengths we have to go to in the ocean environment interesting.

The KISS principle is followed where ever I can too. I sincerely agree.
When things go badly on board, it's rarely one big bad thing that bites
ya. It's a string of small problems that...when combined, lead to a bad
day. I guess that's true in a lot of endeavors come to think of it. Last
time I was in a bad storm (a really bad one at that) I was on the radio
seeking information from someone else who had radar (I do not). My
autohelm had failed (a lousy 25 cent pin broke) and so I had to hand
steer in heavy seas. I couldn't leave the wheel. Fortunately the mic on
my marine VHF radio ~just~ reached the wheel from inside. Unfortunately
that is when I discovered that if I pulled on the mic cable it became
very intermittent. And that led to me spending a half hour trying to
raise a nearby boat with radar to ask which way the storm appeared to be
moving. Then the lightning started hitting the water all around
me...from there...well...let's just say it went downhill some.

Simple is good.

Thanks again for the feedback.
  #22   Report Post  
Old November 28th 04, 04:17 PM
'Doc
 
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Bill,
In most cases, anything you do on a boat is a compromise between
what it 'ought to be' and what's possible. Since the backstay (or
frontstay) is ~there~ anyway, why not use it? Certainly not the
'best' thing in the world (whatever that is), but 'better' than most
alternative$.
Some people have a 'phobia' about tuners. If you don't want to
use one, that's fine. They do make 'things' much easier and the
difference in performance is 'acceptible' in most cases (acceptible
being relative). Since there are alternatives, pick the one you think
you can 'live' with and go with it. "You pays your money and takes your
choice", as they used to say in the house with the red velvet wall paper...
'Doc

PS - Not that I've ever been in one of those houses, I've just read
about them...
  #23   Report Post  
Old November 28th 04, 04:17 PM
'Doc
 
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Bill,
In most cases, anything you do on a boat is a compromise between
what it 'ought to be' and what's possible. Since the backstay (or
frontstay) is ~there~ anyway, why not use it? Certainly not the
'best' thing in the world (whatever that is), but 'better' than most
alternative$.
Some people have a 'phobia' about tuners. If you don't want to
use one, that's fine. They do make 'things' much easier and the
difference in performance is 'acceptible' in most cases (acceptible
being relative). Since there are alternatives, pick the one you think
you can 'live' with and go with it. "You pays your money and takes your
choice", as they used to say in the house with the red velvet wall paper...
'Doc

PS - Not that I've ever been in one of those houses, I've just read
about them...
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Old November 28th 04, 04:21 PM
'Doc
 
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Oops, sorry.

The idea is to make it as 'idiot' proof as possible. That does
not, and will never mean the 'best'...
- 'Doc

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Old November 28th 04, 04:21 PM
'Doc
 
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Oops, sorry.

The idea is to make it as 'idiot' proof as possible. That does
not, and will never mean the 'best'...
- 'Doc



  #26   Report Post  
Old November 28th 04, 07:08 PM
H. Adam Stevens, NQ5H
 
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"'Doc" wrote in message
.. .
Oops, sorry.

The idea is to make it as 'idiot' proof as possible. That does
not, and will never mean the 'best'...
- 'Doc


Make something "idiot-proof" and Nature will just make a better idiot.

73 - H


  #27   Report Post  
Old November 28th 04, 07:08 PM
H. Adam Stevens, NQ5H
 
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"'Doc" wrote in message
.. .
Oops, sorry.

The idea is to make it as 'idiot' proof as possible. That does
not, and will never mean the 'best'...
- 'Doc


Make something "idiot-proof" and Nature will just make a better idiot.

73 - H


  #28   Report Post  
Old November 28th 04, 08:20 PM
Bruce in Alaska
 
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In article ,
James wrote:

the
copper wire I ran up the mast is on it's own pulley (well it will be
when I find time to go up the mast) and is already a lovely shade of
green.


You should replace the copper wire with the stuff the BIG BOYS use.
It is called Phospher/Bronze Antenna wire and it Doesn't turn green
when in contact with Seawater or salt air. Stuff was designed for this
spacific purpose.


Bruce in alaska
--
add a 2 before @
  #29   Report Post  
Old November 28th 04, 08:20 PM
Bruce in Alaska
 
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In article ,
James wrote:

the
copper wire I ran up the mast is on it's own pulley (well it will be
when I find time to go up the mast) and is already a lovely shade of
green.


You should replace the copper wire with the stuff the BIG BOYS use.
It is called Phospher/Bronze Antenna wire and it Doesn't turn green
when in contact with Seawater or salt air. Stuff was designed for this
spacific purpose.


Bruce in alaska
--
add a 2 before @
  #30   Report Post  
Old November 28th 04, 09:50 PM
Cecil Moore
 
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Bill Turner wrote:
Once the antenna is resonant, a simple L-C network will transform the
impedance to 50 ohms resistive and you are all set. Simple, cheap and
reliable, all the things a tuner is not.


And single-banded, one thing a tuner is not. :-)

The antenna need not be resonant. Under certain easily obtainable
conditions, the length of the open-wire transmission line can tune
a non-resonant antenna to system resonance and better the losses in
the coax feeding a resonant antenna. How to do that is described
on my web page.
--
73, Cecil http://www.qsl.net/w5dxp
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