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Ray Andraka
August 8th 03, 03:00 AM
This is one for Jim Weir I guess...

I had one of the Icom antenna switchboxes in my airplane
until this week when I needed the panel space to let my
handheld use the external antenna. I never really cared for
that set-up, it appears it just uses a 1/8 inch phone jack
with the switch in it to disconnect the aircraft radio when
you plug in the handheld. The thought of the handheld's RF
passing within a few mm of the unshielded antenna lead for
the panel mount always bugged me. Anyway, I'd still like to
have the ability to use an external antenna with the
handheld. So far, it looks like the options are:
1) The Icom or similar switch box
2) An extra antenna that is dedicated to the handheld
3) A set up where the antenna cable comes out the panel or
near it so that you can disconnect the antenna and connect
it to the handheld.

The switch box takes up more panel than I'd like, and I have
the reservations already stated. The dedicated antenna
might be a problem because it is only used when your other
radios are already down, and since it is not used regularly
you may not know it is broken until you need it and have no
other backups (other than the rubber ducky antenna on the
handheld).

The antenna cable coming out of the panel and going back in
seems a bit hokey and prone to failure because of the tight
radius bend needed. It also looks like hell.

SO what other options are there?

Ideally, I'd like to have some sort of set up where there is
a dedicated connector on the panel and a select switch that
lets me select either the handheld or the panel mount. It
would also be nice to have the plane's ptt come out to an
adjacent jack so that once the switch is thrown you can
communicate normally (after also plugging into the headphone
adapter on the radio). As I recall, the PTT is a switch
closure to ground, but I'm not sure if I can just connect to
the ship's PTT without first disconnecting it from the
ship's radio (Jim?). What is an appropriate antenna switch
that provides enough isolation to protect both radios from
damaging overload due to the other one transmitting? How
about impedance matches, seems that Icom box does little to
make sure the impedances are properly matched.

--
--Ray Andraka, P.E.
President, the Andraka Consulting Group, Inc.
401/884-7930 Fax 401/884-7950
email
http://www.andraka.com

"They that give up essential liberty to obtain a little
temporary safety deserve neither liberty nor safety."
-Benjamin
Franklin, 1759

Greg Burkhart
August 8th 03, 03:24 AM
See Jim's page http://www.rst-engr.com/kitplanes/KP0203/KP0203.htm (Kitplane
3/02)
Reading through the docs on that page, it disconnects the antenna from the
panel radio when the handheld is plugged in. I started to do this project
but could only find 'cheap' 1/8" phone jacks at RS that the tabs would break
off too easily when soldering on the coax cable. I may attempt this project
again when I can find a decent jack.

"Ray Andraka" > wrote in message
...
> This is one for Jim Weir I guess...
>
> I had one of the Icom antenna switchboxes in my airplane
> until this week when I needed the panel space to let my
> handheld use the external antenna. I never really cared for
> that set-up, it appears it just uses a 1/8 inch phone jack
> with the switch in it to disconnect the aircraft radio when
> you plug in the handheld. The thought of the handheld's RF
> passing within a few mm of the unshielded antenna lead for
> the panel mount always bugged me. Anyway, I'd still like to
> have the ability to use an external antenna with the
> handheld. So far, it looks like the options are:
> 1) The Icom or similar switch box
> 2) An extra antenna that is dedicated to the handheld
> 3) A set up where the antenna cable comes out the panel or
> near it so that you can disconnect the antenna and connect
> it to the handheld.

Ray Andraka
August 8th 03, 03:46 AM
BTW, you can get better quality jacks from either digikey or mouser
electronics. Mouser is better for small orders since there is no fee for
minimum orders. I see Jim also uses Mouser, there is a Mouser label on the back
of the panel he shows in the picture.

Greg Burkhart wrote:

> See Jim's page http://www.rst-engr.com/kitplanes/KP0203/KP0203.htm (Kitplane
> 3/02)
> Reading through the docs on that page, it disconnects the antenna from the
> panel radio when the handheld is plugged in. I started to do this project
> but could only find 'cheap' 1/8" phone jacks at RS that the tabs would break
> off too easily when soldering on the coax cable. I may attempt this project
> again when I can find a decent jack.
>
> "Ray Andraka" > wrote in message
> ...
> > This is one for Jim Weir I guess...
> >
> > I had one of the Icom antenna switchboxes in my airplane
> > until this week when I needed the panel space to let my
> > handheld use the external antenna. I never really cared for
> > that set-up, it appears it just uses a 1/8 inch phone jack
> > with the switch in it to disconnect the aircraft radio when
> > you plug in the handheld. The thought of the handheld's RF
> > passing within a few mm of the unshielded antenna lead for
> > the panel mount always bugged me. Anyway, I'd still like to
> > have the ability to use an external antenna with the
> > handheld. So far, it looks like the options are:
> > 1) The Icom or similar switch box
> > 2) An extra antenna that is dedicated to the handheld
> > 3) A set up where the antenna cable comes out the panel or
> > near it so that you can disconnect the antenna and connect
> > it to the handheld.

--
--Ray Andraka, P.E.
President, the Andraka Consulting Group, Inc.
401/884-7930 Fax 401/884-7950
email
http://www.andraka.com

"They that give up essential liberty to obtain a little
temporary safety deserve neither liberty nor safety."
-Benjamin Franklin, 1759

Michelle P
August 10th 03, 02:00 AM
Ray,

When I had my avionics installed I had them install a third comm antenna
dedicated to the handheld on the belly of the aircraft. The cable comes
out from behind the panel near my left knee and drapes to the floor. I
have used it once when I had electrical failure in IFR and it made the
difference between being able to talk to ATC and them not being able to
hear me at all.

Michelle

Ray Andraka wrote:

>This is one for Jim Weir I guess...
>
>I had one of the Icom antenna switchboxes in my airplane
>until this week when I needed the panel space to let my
>handheld use the external antenna. I never really cared for
>that set-up, it appears it just uses a 1/8 inch phone jack
>with the switch in it to disconnect the aircraft radio when
>you plug in the handheld. The thought of the handheld's RF
>passing within a few mm of the unshielded antenna lead for
>the panel mount always bugged me. Anyway, I'd still like to
>have the ability to use an external antenna with the
>handheld. So far, it looks like the options are:
>1) The Icom or similar switch box
>2) An extra antenna that is dedicated to the handheld
>3) A set up where the antenna cable comes out the panel or
>near it so that you can disconnect the antenna and connect
>it to the handheld.
>
>The switch box takes up more panel than I'd like, and I have
>the reservations already stated. The dedicated antenna
>might be a problem because it is only used when your other
>radios are already down, and since it is not used regularly
>you may not know it is broken until you need it and have no
>other backups (other than the rubber ducky antenna on the
>handheld).
>
>The antenna cable coming out of the panel and going back in
>seems a bit hokey and prone to failure because of the tight
>radius bend needed. It also looks like hell.
>
>SO what other options are there?
>
>Ideally, I'd like to have some sort of set up where there is
>a dedicated connector on the panel and a select switch that
>lets me select either the handheld or the panel mount. It
>would also be nice to have the plane's ptt come out to an
>adjacent jack so that once the switch is thrown you can
>communicate normally (after also plugging into the headphone
>adapter on the radio). As I recall, the PTT is a switch
>closure to ground, but I'm not sure if I can just connect to
>the ship's PTT without first disconnecting it from the
>ship's radio (Jim?). What is an appropriate antenna switch
>that provides enough isolation to protect both radios from
>damaging overload due to the other one transmitting? How
>about impedance matches, seems that Icom box does little to
>make sure the impedances are properly matched.
>
>--
>--Ray Andraka, P.E.
>President, the Andraka Consulting Group, Inc.
>401/884-7930 Fax 401/884-7950
>email
>http://www.andraka.com
>
> "They that give up essential liberty to obtain a little
> temporary safety deserve neither liberty nor safety."
> -Benjamin
>Franklin, 1759
>
>
>
>

--

Michelle P CP-ASMEL-IA, and AMT-A&P

"Elisabeth" a Maule M-7-235B (no two are alike)

Volunteer Pilot, AirLifeLine

Volunteer Builder, Habitat for Humanity

Jim Weir
January 16th 04, 05:45 PM
Good god, this one got stuck in a time warp. Sorry it took me so long to answer
it.

www.rstengineering.com/kitplanes and then to the July 2002 article.

Jim



Ray Andraka >
shared these priceless pearls of wisdom:

->This is one for Jim Weir I guess...
-
->3) A set up where the antenna cable comes out the panel or
->near it so that you can disconnect the antenna and connect
->it to the handheld.
Jim Weir (A&P/IA, CFI, & other good alphabet soup)
VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
http://www.rst-engr.com

john smith
January 16th 04, 10:17 PM
Jim Weir wrote:
> Good god, this one got stuck in a time warp. Sorry it took me so long to answer
> it.
> www.rstengineering.com/kitplanes and then to the July 2002 article.


Jim, what happened to the volunteer project to bring the newer articles
into pdf form for you to post?

Jim Weir
January 16th 04, 11:20 PM
It, too, is underway beginning yesterday.

Jim

john smith >
shared these priceless pearls of wisdom:

->Jim Weir wrote:
->> Good god, this one got stuck in a time warp. Sorry it took me so long to
answer
->> it.
->> www.rstengineering.com/kitplanes and then to the July 2002 article.
->
->
->Jim, what happened to the volunteer project to bring the newer articles
->into pdf form for you to post?

Jim Weir (A&P/IA, CFI, & other good alphabet soup)
VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
http://www.rst-engr.com

Ray Andraka
March 5th 04, 02:10 PM
Jim, you mentioned in this article tht you were considering a device to control
electrical outlets with a beeper signal. Didya ever do it?

Jim Weir wrote:

> Good god, this one got stuck in a time warp. Sorry it took me so long to answer
> it.
>
> www.rstengineering.com/kitplanes and then to the July 2002 article.
>
> Jim
>
> Ray Andraka >
> shared these priceless pearls of wisdom:
>
> ->This is one for Jim Weir I guess...
> -
> ->3) A set up where the antenna cable comes out the panel or
> ->near it so that you can disconnect the antenna and connect
> ->it to the handheld.
> Jim Weir (A&P/IA, CFI, & other good alphabet soup)
> VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
> http://www.rst-engr.com

--
--Ray Andraka, P.E.
President, the Andraka Consulting Group, Inc.
401/884-7930 Fax 401/884-7950
email
http://www.andraka.com

"They that give up essential liberty to obtain a little
temporary safety deserve neither liberty nor safety."
-Benjamin Franklin, 1759

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