Long wire HF Antenna Length

[nhschneider]

Originally Posted by Goudurix

Hi nhschneider,

Since for both an insulated backstay or wire antenna ("alternate backstay antenna) you need the automatic tuner and a way to bring down a wire or GTO-15 through the deck towards the antenna lug of the tuner, you have nothing to lose trying out hte cheaper solution first you will only need the stretch of AWG12 wire and2 or 3 cheap HAM isolators at $ 0,50 a piece.

What does matter is to have the wire run a bit away from other stays, shrouds etc as your antenna wire will couple into those and distort radiation pattern however on a sailing boat this is unavoidable...

For a trial setup there is no need to run the wire inside a dacron rope.

30 feet should do well (30 feet from top of the wire at the top isolator until the antenna tuner's antenna connection lug). This should give you good to very good operation 7 Mhz - 22 Mhz losing some efficiency lower than 7 Mhz.

Another low(er) cost experiment/solution is to use a 7m fishing rod, run the wore alongside the rod, and install this at the aft pulpit. This will probably give you about 7,3-8 meters of total antenna length, I would rather go for about 7,3 m to avoid 1/2 wavelength on 18 Mhz HAM band. I guess this is a good solution to get a bit farther away from the standing rigging but not a very sturdy one so I would go for the 30 ft wire antenna from the mizzen if it doesn't interfere with the mizzen boom off course.

Jan

Jan-
Thanks very much for the information.

I'm not exactly sure what a 'HAM isolator' is - I found a T-4 Islolator on-line at US$35.00 but it didn't sound like what you're describing.

Also, are you sure you mean a 7m fishing pole? That's a pretty long fishing pole! Or is this a radio term that I should know?

I installed an Icom 802 with the AT-140 tuner when we were in Australia but it hasn't worked very well. My old Icom 800 boomed out a signal but the previous owner had that grounded to a cleat in the cockpit. I ran all new copper foil from the tuner to the Dynaplate and now no one can hear me. I just ordered a KISS system so I'm going to give that a try.

Again, thanks for your help.

73s.
KE6FXX

[Goudurix]

Hi again,

no a "Ham-style" wire isolator is just a black plastic isolator with a hole on both sides to fix a wire or rope.

It is really cheap. You could even make your own from small diameter PVC tubing but the HAM ones are massive plastic so stronger. (Nothing to do with the expensive isolators to insulate a backstay).

7 m fishing rods are easily available though today they usually contain carbon and not glass fibre which means they are conducting but this would not be a problem in the "random end fed wire antenna" this technically is. Just tape or strap the antenna wire along the fishing pole.

They can be quite cheap $30-$50 those are the cheaper ones but once again I think this would rather be a good emergency antenna setup but not sturdy enough for permanent installation.

Sturdy HF pole antenna's (e.g. Shakespeare) exist but are a lot more expensive but I guess less expensive than having your backstay insulated.

Jan

[ka4wja]

Neal,
(Please confirm WHERE you are at...in/near San Diego or are you in/near Thailand?? or other locale???)

1) Cancel your order for the KISS....it will NOT help you!!


2) There are two well-known problems/issues with the Icom M-802, that any Icom marine electronics dealer/installer should know about, that will cause the exact problem you describe...and both have simple and inexpensive fixes!!

And both can cause the problems that you describe!!!

(And neither of these problems/issues effect data/digital communications, but only Voice transmissions...)

Originally Posted by nhschneider

I installed an Icom 802 with the AT-140 tuner when we were in Australia but it hasn't worked very well. My old Icom 800 boomed out a signal but the previous owner had that grounded to a cleat in the cockpit. I ran all new copper foil from the tuner to the Dynaplate and now no one can hear me. I just ordered a KISS system so I'm going to give that a try.

--- One is the dreaded "clipping issue".... that affected most earlier M-802 versions (even "new" ones that are New Old Stock, sitting on the shelves for a while), Icom has an easy fix for this and it is FREE!!!
Please read this thread/discussion, where you WILL find detailed descriptions of the problem, how to recognize this problem, what radio serial numbers it effected (and which ones it did not), and procedures for having the Icom factory "clipping mod" done (which solves the problem for good!!)

Icom M-802 "Clipping Issue" - Revisited....
SSCA Forum • View topic - Icom M-802 "Clipping Issue" - Revisited....




--- The other is the fact that most M-802's are shipped with the internal DSP Speech Compressor turned Off, thereby significantly reducing the radio's average power output / "talk-power"....

Please read this thread/discussion, where you WILL find a detailed description of the issue, as well as solutions to solving the problem (requires someone with the "cloning software" / programming software to turn "On" the speech compressor, which might cost you a cold beer or a sandwich, etc. or maybe as much as $100 for a professional shop...or maybe a bit more if you wish to have a "hardware mod" done, but this is usually not necessary..._

IC-M802 Compression
SSCA Forum • View topic - IC-M802 Compression





3) Please have a look at this thread, and watch the videos, where you'll learn a LOT about the M-802...

Icom M-802 Instr Videos(basic-adv) & LIVE DSC-Distress Call
http://www.cruisersforum.com/forums/...ll-114734.html




4) If you wish to learn why the KISS is a waste of your money (and learn a lot of other cool radio stuff as well), have a look at this thread/discussion....

Re: KISS-SSB Counterpoise
SSCA Forum • View topic - KISS-SSB Counterpoise














5) Neal, without having any more details from you about your M-802, other than what you wrote....I cannot be 100% certain, but I'm > 95% sure that it is either one, or both, of the above problems ("clipping issue" and "speech compressor is Off"), that is causing your difficulties!!!

Please read those threads, see if what they describe sounds like your problem (I think it's spot on!!), AND provide us with some further info....

Further info, such as:
a) Where does your power output meter (the 8 segment bar graph on the M-802's display) deflect to when you are transmitting and speaking in a normal, but direct voice, with the mic 1" - 2" directly in front of your mouth???

b) Do some of your words get thru, but not others??? Do some of your words/syllables get cut-off???

c) Do you get a steady "Tune" indication on the M-802's display??

d) Do you have the M-802 set to "Hi Power"???
e) Select FSK mode, and press the mic's PTT button, and verify that you get full deflection on the M-802's power output meter display??

f) Please confirm WHERE you are at....
AND...
Let us know about who/where/when/what freqs used for contacting others (the ones that say they can't hear you...)
Please be specific...

WHERE???
WHO???
At WAHT time-of-day???
WHAT FREQUENCY???



There's more....but that will do for now...



Please cancel your KISS order, READ those threads/discussions, and confirm/answer these questions...




6) BTW, if you already have backstay insulators, there is little reason not to use them...

But using an "alternative backstay" (whether just a copper wire, SS lifeline wire, or copper wire in Dacron/poly rope) will be a less expensive approach, and as Jan has pointed out keeping this away from your other rigging is important, but sometimes difficult (hence one reason why backstays have been the standard approach for 50 years!!)

If you have the budget, nothing beats the Hayn Hi-Mod failsafe rigging insulators....they're pricey, but will literally out-last you and your boat....




Fair winds...
73,

John
s/v Annie Laurie