I supose that one could make a trap-vertical to avoid a tuner, but
I've never seen one for marine bands. I do recall a version of the
OutBacker that was for marine use but have never known anyone
that had one.

Doug, k3qt
s/v Callista

"Chuck" wrote in message
ink.net...
Hey there, Doug,

I guess I took your question of

How do you get away without a tuner?

too literally! Obviously you've been doing it for years.

73,

Chuck


Doug Dotson wrote:
Comments below.

"Chuck" wrote in message
link.net...

Doug, it's difficult to generalize but in many cases the radiation
resistance of a whip will be in the range of 20 to 35 ohms (assuming the
whip is a quarter-wave or somewhat shorter) and the ground resistance in
series with that may be another 25 ohms or so. What you get is a
feedpoint impedance of about 45 to 60 ohms (could be more or less) which
will match 50 ohm coax very nicely without a tuner. Most transmitters
will feed loads of 25 to 100 ohms (2:1 swr) without complaining. For a
short run of coax, your total losses will probably be less than if you
used a tuner.


Agreed.


It is true that you can only use such an antenna for a single marine or
ham band.


And as such is an inconvenient situation on a boat.


Even then, at the lower frequencies, you will experience a limited band
of frequencies that you can use without a tuner. On 8 MHz and above, you
will probably find that an antenna cut for the middle of the band will
cover the whole band nicely.


SOP for single band antennas unless one is interested in only a
subsection
of the band in which case one cuts it for the center of the segment of
interest.


A lot of cruisers keep a 14 MHz "Hamstick" on board as an emergency
antenna they can use if their tuner fails or if (heaven forbid) they are
dis-masted and can't use their backstay antenna.


I have Hamsticks for 80, 40, 20, and 15M. They were my only antennas
for a long time before I insulated the backstay and got an SGC auto
tuner. I still hang on to the Hamsticks as backups though. When I got
another boat that already had a 23' whip, I found that it worked better
than the backstay on my previous boat, so I have stuck with it.


In an emergency you can check in to the Maritime Mobile Service Net on
14.300 MHz even if you're not a ham. It is one of the few frequencies
monitored almost continuously by experienced operators.


I have been checking into the MMSN for years now. Actually, the MMSN
is only in operation during certain hours (1200 to 2000 Eastern time).
Other
nets are in operation during other hours (Coast Guard Net, InterCon, etc)
In an emergency you can check into anything anywhere.


The Hamstick is easy to store, easy to install, and once adjusted, should
be trouble-free. To switch bands, you switch Hamsticks. They even make a
quick-connect gizmo.


Been using them for years.


There are other makes as well. But if you don't use something like a
Hamstick, and just use a longer whip like a 16 foot whip, it will be good
for just one band. Actually, 16 feet is close to a quarter-wave on 20
meters so you may be able to use it as-is without a tuner on that band.
If you're not comfortable doing the hookup, find a local ham to advise
you. They're usually glad to help.


I am a local ham I help myself alot


Good luck!


Thanks!
Doug, k3qt
s/v Callista

It's hard to believe the marine version of the Outbacker was very
efficient, but it probably was better than nothing at all.

Yeah, other than traps, the only other reliable technique I can think of
for a multiband (as opposed to simply a "wideband") antenna is to use
switched, tuned feeders (open wire line stubs actually, cut to tune a
dipole to each band). I have a difficult time imagining that on a
sailboat! Anyway, that stretches the idea of "no tuner", but at least
there are no moving parts other than the band switch.

Well, now that I think of it, there are some common antennas that work
on more than one band without a tuner or traps. A simple 40 meter dipole
(or quarter-wave vertical) ought to work on 15 meters, for example. And
the G5RV, and some sky loop antennas are multiband. A vertical (cut the
horizontal one in half) G5RV would be interesting to consider. I don't
think I've encountered that before and matching might be interesting,
but it may have potential for backstay antennas. These antennas usually
benefit from a rig with a built-in tuner, so maybe they should be
"disqualified" as not tuner-less.

Chuck, NT3G
s/v Sans Serif

Doug Dotson wrote:
I supose that one could make a trap-vertical to avoid a tuner, but
I've never seen one for marine bands. I do recall a version of the
OutBacker that was for marine use but have never known anyone
that had one.

Doug, k3qt
s/v Callista

In article ,
"Doug Dotson" wrote:

I supose that one could make a trap-vertical to avoid a tuner, but
I've never seen one for marine bands. I do recall a version of the
OutBacker that was for marine use but have never known anyone
that had one.

Doug, k3qt
s/v Callista

Morad Electronics of Seattle has been making Trapped Verticles for
4-22Mhz for years. They were pioneered by Ed Zanbergen back in
the late 60's, and have been a fixture in the North Pacific Commercial
Fleet ever since.


Bruce in alaska
--
add a 2 before @

But are the traps tuned for the marine bands? I've had many trap
verticals for ham bands and trap dipoles as well.

Doug, k3qt
s/v Callista

"Bruce in Alaska" wrote in message
...
In article ,
"Doug Dotson" wrote:

I supose that one could make a trap-vertical to avoid a tuner, but
I've never seen one for marine bands. I do recall a version of the
OutBacker that was for marine use but have never known anyone
that had one.

Doug, k3qt
s/v Callista

Morad Electronics of Seattle has been making Trapped Verticles for
4-22Mhz for years. They were pioneered by Ed Zanbergen back in
the late 60's, and have been a fixture in the North Pacific Commercial
Fleet ever since.


Bruce in alaska
--
add a 2 before @

In article ,
"Doug Dotson" wrote:

But are the traps tuned for the marine bands? I've had many trap
verticals for ham bands and trap dipoles as well.

Doug, k3qt
s/v Callista

"Bruce in Alaska" wrote in message
...
In article ,
"Doug Dotson" wrote:

I supose that one could make a trap-vertical to avoid a tuner, but
I've never seen one for marine bands. I do recall a version of the
OutBacker that was for marine use but have never known anyone
that had one.

Doug, k3qt
s/v Callista

Morad Electronics of Seattle has been making Trapped Verticles for
4-22Mhz for years. They were pioneered by Ed Zanbergen back in
the late 60's, and have been a fixture in the North Pacific Commercial
Fleet ever since.


Bruce in alaska
--
add a 2 before @



Oh yea, they are specific for the Marine Bands. These were designed
specifically for use on Maritime Mobile Frequencies in the HF range.
While Eddie Zanbergen was alive, he was one of the worlds formost
Marine Antenna System Designers. He also build special versions
of most of his popular Marine Antennas, for the Ham market as well,
but most hams wouldn't pay the price for a commercial grade antenna,
so they were custom built on demand. I have a bunch of these special
antennas, that Ed built for me, that I have never had a place to install,
but when I finish my Retirement House, they will all be part of the
antenna array that goes along with that project. Morad still makes
the VHF-HD10db Base Stataion Antenna in both Marine and Ham versions.
This antenna is the STANDARD throught the North Pacific for Coast
Stations and Vessels over 60 Ft. You will not find any other antenna
on 99% of the Bering Sea Crab Fleet, as they need the MOST Rugged,
and Weather Resistant Antenna available. This one is the REAL DEAL.
I have seen Super Station Masters, twisted up like a Pretzel and a
Morad still standing on the same tower, after a 130 Kt wind storm.


Bruce in alaska
--
add a 2 before @

"Bruce in Alaska" wrote in message
...
In article ,
"Doug Dotson" wrote:

I supose that one could make a trap-vertical to avoid a tuner, but
I've never seen one for marine bands. I do recall a version of the
OutBacker that was for marine use but have never known anyone
that had one.

Doug, k3qt
s/v Callista

Morad Electronics of Seattle has been making Trapped Verticles for
4-22Mhz for years. They were pioneered by Ed Zanbergen back in
the late 60's, and have been a fixture in the North Pacific Commercial
Fleet ever since.


Bruce in alaska
--
add a 2 before @

Bruce,
You beat me to it. I had time to go to the Morad site today, only to find it
is down to a one page "under construction" page right now. While referencing
their sales literature in our files, I was called out on a repair, so I
didn't have time to post here until now. I did not see the trap marine band
vertical in their current price sheet, but I bet they still make them. You
can't go into a commercial fishing port in the Pacific NW without seeing a
least one, and sometimes three Morad trap vertical antennas, some with
capacity hats on the fishing boats. They make an excellent VHF marine
antenna also, and even a 2 meter ham band variation. This is also a
commercial fishing and tug boat standard in this area. It mounts on a 1" OD
pipe and is very rugged. Definitely a step up from fiberglass recreational
boat whips.
Doug K7ABX

SOunds like a step up since there are no fiberglass trap verticals
for recreational boats as far as I can tell.

Doug, k3qt
s/v Callista

"Doug" wrote in message
hlink.net...

"Bruce in Alaska" wrote in message
...
In article ,
"Doug Dotson" wrote:

I supose that one could make a trap-vertical to avoid a tuner, but
I've never seen one for marine bands. I do recall a version of the
OutBacker that was for marine use but have never known anyone
that had one.

Doug, k3qt
s/v Callista

Morad Electronics of Seattle has been making Trapped Verticles for
4-22Mhz for years. They were pioneered by Ed Zanbergen back in
the late 60's, and have been a fixture in the North Pacific Commercial
Fleet ever since.


Bruce in alaska
--
add a 2 before @

Bruce,
You beat me to it. I had time to go to the Morad site today, only to find
it
is down to a one page "under construction" page right now. While
referencing
their sales literature in our files, I was called out on a repair, so I
didn't have time to post here until now. I did not see the trap marine
band
vertical in their current price sheet, but I bet they still make them. You
can't go into a commercial fishing port in the Pacific NW without seeing
a
least one, and sometimes three Morad trap vertical antennas, some with
capacity hats on the fishing boats. They make an excellent VHF marine
antenna also, and even a 2 meter ham band variation. This is also a
commercial fishing and tug boat standard in this area. It mounts on a 1"
OD
pipe and is very rugged. Definitely a step up from fiberglass recreational
boat whips.
Doug K7ABX