The other day I was wandering around one of our marinas trying to steal
ideas from other boats and I came across an aluminum pilot-house sloop that
may have come over from Europe. I noticed that the SSB coax was held away
from the backstay turnbuckle and wire by ~1 inch plastic spacers. I've
never seen this before and the previous owner didn't do it on my boat. I've
been thinking of upgrading the ancient SSB system on my boat and was
wondering if these standoffs were something recommended.
Anyone know about these? Thanks
Gord

"Gordon Wedman" wrote:

The other day I was wandering around one of our marinas trying to steal
ideas from other boats and I came across an aluminum pilot-house sloop that
may have come over from Europe. I noticed that the SSB coax was held away
from the backstay turnbuckle and wire by ~1 inch plastic spacers. I've
never seen this before and the previous owner didn't do it on my boat. I've
been thinking of upgrading the ancient SSB system on my boat and was
wondering if these standoffs were something recommended.
Anyone know about these? Thanks
Gord

Standoffs are highly recommended to eliminate coupling/signal loss between the
leadin and the backstay below the insulators. I made mine by running plastic
wire ties through shrink wrap tubing-a loop around the backstay, through the
tubing, a loop around the wire. About 2" long is good. Not coax at this point,
but High Voltage wire, BTW. Easy to do, and does help performance.

I think I read somewhere that the high voltage GTO wire should optimumly
approach the backstay at right angles. Something about when the lead
runs close and parallel to the grounded section some power is leached
off. Not real practical in most cases though. Stand offs about 1 1/2"
long keep the lead wire away from the stay enough to prevent significant
loss and are a pretty good way to keep things neat but probably not the
most electrically efficient.

OTOH, if you have this RF hot wire running up the stay where anyone can
grab it, why have a lower insulator in the first place? I am
considering not grounding the backstay chainplate and feeding the tuner
directly to one of the bolts. Just have to remember to yell "If you
have to pee off the stern rail Don't hold the backstay!" before sending
any e-mail. :-)

Gordon Wedman wrote:
The other day I was wandering around one of our marinas trying to steal
ideas from other boats and I came across an aluminum pilot-house sloop that
may have come over from Europe. I noticed that the SSB coax was held away
from the backstay turnbuckle and wire by ~1 inch plastic spacers. I've
never seen this before and the previous owner didn't do it on my boat. I've
been thinking of upgrading the ancient SSB system on my boat and was
wondering if these standoffs were something recommended.
Anyone know about these? Thanks
Gord



--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

If it is feeding a backstay, coax is not the best solution. GTO-15
high voltage wire is the proper choice. If the lower part of the
backstay is insulated from the rest of the boat then standoffs
are not necessary but the part below the insulator becomes part of
the antenna. Don't touch it while transmitting. If the lower part
of the backstay is connected to the bonding systems or a metal hulled
boat then insulators are necessary. The cheapest ones I have seen are short
lengths
of PVC pipe notched at the ends to nestle against the wire and backstay.
Then
a wire-tie is threaded around the backstay, through the pipe, around the
wire and back. Works well and is cheap. Probably have to replace them
every couple of years due to UV degradation.

Doug, k3qt
s/v Callista

"Gordon Wedman" wrote in message
news:JMfqb.136245$EO3.29023@clgrps13...
The other day I was wandering around one of our marinas trying to steal
ideas from other boats and I came across an aluminum pilot-house sloop
that
may have come over from Europe. I noticed that the SSB coax was held away
from the backstay turnbuckle and wire by ~1 inch plastic spacers. I've
never seen this before and the previous owner didn't do it on my boat.
I've
been thinking of upgrading the ancient SSB system on my boat and was
wondering if these standoffs were something recommended.
Anyone know about these? Thanks
Gord

I see this all the time on cruising boats not most, not many but a
few. I always try to argue with the person that installed it on the
pros and cons but never get anyone that can talk rf to me. best I had
was an extra class ham that just said it works better because I can
hear the difference.

Distributed capacitance should be taken care of by the antenna tuner
(all random length end fed vertical wire antennas on boats have tuners
I think) So I guess the reason is to keep stray rf from coupling and
reflecting back from the backstay. I would think that a ¼ wavelength
distance from the backstay to the gto-15 should be good. But since you
will be using it on many bands I would guess that at least 1/8
wavelength at the lowest frequency would be someplace to start from.
Maybe about 10 meters separation between backstay and gto-15 may make
a measurable difference. 2 inches of separation, less then 1
electrical degree ROTFLMAO at anyone who says it makes a difference.





sded wrote in message . ..
"Gordon Wedman" wrote:

The other day I was wandering around one of our marinas trying to steal
ideas from other boats and I came across an aluminum pilot-house sloop that
may have come over from Europe. I noticed that the SSB coax was held away
from the backstay turnbuckle and wire by ~1 inch plastic spacers. I've
never seen this before and the previous owner didn't do it on my boat. I've
been thinking of upgrading the ancient SSB system on my boat and was
wondering if these standoffs were something recommended.
Anyone know about these? Thanks
Gord

Standoffs are highly recommended to eliminate coupling/signal loss between the
leadin and the backstay below the insulators. I made mine by running plastic
wire ties through shrink wrap tubing-a loop around the backstay, through the
tubing, a loop around the wire. About 2" long is good. Not coax at this point,
but High Voltage wire, BTW. Easy to do, and does help performance.

If the backstay turnbuckle were "hot" (energized with RF) this would
be prudent because there can be considerable voltages from the tuner
on certain frequencies, such as near when the backstay is a 1/2
wavelength antenna.

The question arises, why does the coax go to the backstay AT ALL? It
goes to the TUNER who's tuned RF output goes to the backstay. I has
no business going to the backstay.

The wire from the tuner's high voltage post to the backstay shouldn't
be coax, either. Coax has LOTS of capacitance to the shield and if
some idiot grounds it it will decouple the RF off to ground at the
higher impedances.... A heavy wire should hook the tuner to the
backstay as it's just part of the antenna.



On Wed, 05 Nov 2003 23:32:57 GMT, "Gordon Wedman"
wrote:

The other day I was wandering around one of our marinas trying to steal
ideas from other boats and I came across an aluminum pilot-house sloop that
may have come over from Europe. I noticed that the SSB coax was held away
from the backstay turnbuckle and wire by ~1 inch plastic spacers. I've
never seen this before and the previous owner didn't do it on my boat. I've
been thinking of upgrading the ancient SSB system on my boat and was
wondering if these standoffs were something recommended.
Anyone know about these? Thanks
Gord




Larry W4CSC

"Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!"

It was probably GTO-15. I would hope that who ever went to the trouble
of adding the standoffs would know the difference. GTO is hard to tell
from RG59 from a distance. Neon sign suppliers even have it in
decorator colors.

Larry W4CSC wrote:

If the backstay turnbuckle were "hot" (energized with RF) this would
be prudent because there can be considerable voltages from the tuner
on certain frequencies, such as near when the backstay is a 1/2
wavelength antenna.

The question arises, why does the coax go to the backstay AT ALL? It
goes to the TUNER who's tuned RF output goes to the backstay. I has
no business going to the backstay.

The wire from the tuner's high voltage post to the backstay shouldn't
be coax, either. Coax has LOTS of capacitance to the shield and if
some idiot grounds it it will decouple the RF off to ground at the
higher impedances.... A heavy wire should hook the tuner to the
backstay as it's just part of the antenna.



On Wed, 05 Nov 2003 23:32:57 GMT, "Gordon Wedman"
wrote:


The other day I was wandering around one of our marinas trying to steal
ideas from other boats and I came across an aluminum pilot-house sloop that
may have come over from Europe. I noticed that the SSB coax was held away

from the backstay turnbuckle and wire by ~1 inch plastic spacers. I've

never seen this before and the previous owner didn't do it on my boat. I've
been thinking of upgrading the ancient SSB system on my boat and was
wondering if these standoffs were something recommended.
Anyone know about these? Thanks
Gord





Larry W4CSC

"Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!"


--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

On Thu, 06 Nov 2003 09:29:20 -0500, Glenn Ashmore
wrote:

It was probably GTO-15. I would hope that who ever went to the trouble
of adding the standoffs would know the difference. GTO is hard to tell
from RG59 from a distance. Neon sign suppliers even have it in
decorator colors.

What the hell is GTO-15, some West Marine $20/ft trick? This isn't a
neon sign with 40KV of 60 Hz on it....IT'S RF! All the insulation in
the world isn't going stop the RF from leaking out, like it's 'spozed
ta. Lionheart's tuner is hooked to its backstay with a stainless
strap in a gentle curve held on with a stainless hose clamp.

Now that we got the damned steel cable holdin' the boom up replaced
with something that DOESN'T suck off the HF signal into the mainmast,
it works much better......well, at least until the sun exploded wiping
out the ionosphere....

73 DE W4CSC

NNNN

AR

GTO-15 is 15KV insulated wire and fairly standard for tuner to backstay
leads. More for safety than efficiency. The whole idea of elevated
lower insulator on the backstay is to prevent some dumb crew member from
grabbing a hot lead and getting an RF burn. The GTO limits that
possibility. The stainless strap approaching at an angle is probably
more efficient and neater looking but gives no protection. West Moron
dropped it from the Catalog this year but used to sell it for $1/ft. It
is standard material in neon shops for $.50/ft and from HVAC dealers as
spark igniter wire for $.25/ft.

Larry W4CSC wrote:

On Thu, 06 Nov 2003 09:29:20 -0500, Glenn Ashmore
wrote:


It was probably GTO-15. I would hope that who ever went to the trouble
of adding the standoffs would know the difference. GTO is hard to tell

from RG59 from a distance. Neon sign suppliers even have it in

decorator colors.


What the hell is GTO-15, some West Marine $20/ft trick? This isn't a
neon sign with 40KV of 60 Hz on it....IT'S RF! All the insulation in
the world isn't going stop the RF from leaking out, like it's 'spozed
ta. Lionheart's tuner is hooked to its backstay with a stainless
strap in a gentle curve held on with a stainless hose clamp.

Now that we got the damned steel cable holdin' the boom up replaced
with something that DOESN'T suck off the HF signal into the mainmast,
it works much better......well, at least until the sun exploded wiping
out the ionosphere....

73 DE W4CSC

NNNN

AR


--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Thanks to all for the discussion. For the minimal effort and expense it
sounds like a good way to save a bit of transmit power.
Sorry about the reference to "coax". As I'm not very knowledgeable about
these things I couldn't really state what type of wire it was and just
guessed coax. Thanks for pointing out the correct wire to use. I don't
think my boat currently has this.

"Gordon Wedman" wrote in message
news:JMfqb.136245$EO3.29023@clgrps13...
The other day I was wandering around one of our marinas trying to steal
ideas from other boats and I came across an aluminum pilot-house sloop
that
may have come over from Europe. I noticed that the SSB coax was held away
from the backstay turnbuckle and wire by ~1 inch plastic spacers. I've
never seen this before and the previous owner didn't do it on my boat.
I've
been thinking of upgrading the ancient SSB system on my boat and was
wondering if these standoffs were something recommended.
Anyone know about these? Thanks
Gord