Ham Radio In The Airplane

"Jim Weir" wrote in message
...
I don't know. I've never used a handheld. I've got a Kenwood 231 mounted
like
an airplane radio in the stack and plumbed through the audio panel to the
headsets.


Are the mike inputs and audio outputs compatible with the aviation headset
impedance?

I'm a lapsed ham and am considering 2M Aero mobile. I find I know NOTHING
about the
present day equipment. When I was active, everything had nice filaments to
keep stuff warm G

I'd like to find a piece of 2 meter gear that is generally plug and play.
I'll stick a 19 inch on the belly
of my aircraft, and take to the airwaves----AFTER I retake the exams.

I let an advanced class license lapse. (*&^^%$

Thanks

Paul Anton
ex WA6NXL WA7ESD HL9VL

"Paul"
shared these priceless pearls of wisdom:

-
-"Jim Weir" wrote in message
.. .
- I don't know. I've never used a handheld. I've got a Kenwood 231 mounted
-like
- an airplane radio in the stack and plumbed through the audio panel to the
- headsets.
-
-
-Are the mike inputs and audio outputs compatible with the aviation headset
-impedance?

Not really. The standard aircraft mic simulates an old carbon element. You get
roughly half a volt to a volt p-p across something like 300 ohms. A standard
dynamic input to a ham rig is a few millivolts across a couple of dozen ohms. A
standard electret input is a couple of tenths of a volt across 2K or so.

The standard aircraft earphone wants a volt or two p-p across 150 ohms. The
normal ham rig output is speaker level (a couple of volts into 8 ohms).

The point is, there IS no ham radio standard, while the aircraft headset
standard is quite well defined. You can't just hook the aircraft headset into
the ham rig on a PNP basis. You always wind up dicking around with voltage and
impedance shifters to make it play well.

Jim

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

In rec.aviation.owning Jim Weir wrote:
"Paul"
shared these priceless pearls of wisdom:

-
-"Jim Weir" wrote in message
.. .
- I don't know. I've never used a handheld. I've got a Kenwood 231 mounted
-like
- an airplane radio in the stack and plumbed through the audio panel to the
- headsets.
-
-
-Are the mike inputs and audio outputs compatible with the aviation headset
-impedance?

Not really. The standard aircraft mic simulates an old carbon element. You get
roughly half a volt to a volt p-p across something like 300 ohms. A standard
dynamic input to a ham rig is a few millivolts across a couple of dozen ohms. A
standard electret input is a couple of tenths of a volt across 2K or so.

The standard aircraft earphone wants a volt or two p-p across 150 ohms. The
normal ham rig output is speaker level (a couple of volts into 8 ohms).

The point is, there IS no ham radio standard, while the aircraft headset
standard is quite well defined. You can't just hook the aircraft headset into
the ham rig on a PNP basis. You always wind up dicking around with voltage and
impedance shifters to make it play well.

Jim

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

FWIW, the July QST Hints & Kinks column had this discussion with a simple
circuit to use an aviation headset with a ham rig.

--
Jim Pennino

On Sat, 05 Jul 2003 17:18:26 -0700, Jim Weir wrote:

I don't know. I've never used a handheld. I've got a Kenwood 231 mounted like
an airplane radio in the stack and plumbed through the audio panel to the
headsets.

The antenna is a 19" piece of brazing rod on a connector mounted to the outboard
rib and inside the plastic wingtip. The rib and the rest of the wing form the
ground plane.

Range? I've had 100-150 mile contacts at 10K' like they were in the copilot's
seat. At greater ranges they drop off like an orange off a table. At that
altitude, power and sensitivity mean damned little; radio horizon is everything.


I get about the same with a 5 Watt hend held to 50 watt mobiles on
146.52.

I hook the belt clip on the door strap leaving the antenna sticking up
in the window. The I use one of the little ear pieces under my
aviation head set and a noise canceling lapel mike with PTT,

Works like a charm.

Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)

snip

On Sun, 6 Jul 2003 16:32:41 +0000 (UTC), Jim Pennino
wrote:

In rec.aviation.owning Jim Weir wrote:
"Paul"
shared these priceless pearls of wisdom:

-
-"Jim Weir" wrote in message
.. .
- I don't know. I've never used a handheld. I've got a Kenwood 231 mounted
-like
- an airplane radio in the stack and plumbed through the audio panel to the
- headsets.
-
-
-Are the mike inputs and audio outputs compatible with the aviation headset
-impedance?

Not really. The standard aircraft mic simulates an old carbon element. You get
roughly half a volt to a volt p-p across something like 300 ohms. A standard
dynamic input to a ham rig is a few millivolts across a couple of dozen ohms. A
standard electret input is a couple of tenths of a volt across 2K or so.

The standard aircraft earphone wants a volt or two p-p across 150 ohms. The
normal ham rig output is speaker level (a couple of volts into 8 ohms).

The point is, there IS no ham radio standard, while the aircraft headset
standard is quite well defined. You can't just hook the aircraft headset into
the ham rig on a PNP basis. You always wind up dicking around with voltage and
impedance shifters to make it play well.

Jim

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

FWIW, the July QST Hints & Kinks column had this discussion with a simple
circuit to use an aviation headset with a ham rig.

It's far, far simpeler to just get one of the little ear pieces with
the small lapel mike. Probably cheaper in the long run ...

They are inexpensive so why bother messing around with a good head set
when you don't have to.

Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)

Because there are those of us who see clipping a handheld to a window with a
rubber duckie is not the way we want to do things. Why buy a $300 headset and
an audio panel to get the best possible audio into your aircraft transceiver if
you aren't willing to do the same thing for your ham rig?

It really ain't rocket science, and besides, somewhere I read that "fostering
advancement of the state of the radio art" had a place in Part 97.

Jim


-
-They are inexpensive so why bother messing around with a good head set
-when you don't have to.
-
-Roger Halstead (K8RI EN73 & ARRL Life Member)
-www.rogerhalstead.com
-N833R World's oldest Debonair? (S# CD-2)


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

Jim Weir writes:

Because there are those of us who see clipping a handheld to a window with a
rubber duckie is not the way we want to do things. Why buy a $300 headset and
an audio panel to get the best possible audio into your aircraft transceiver if
you aren't willing to do the same thing for your ham rig?

It really ain't rocket science, and besides, somewhere I read that "fostering
advancement of the state of the radio art" had a place in Part 97.

Yep.

I just got done adapting an IC207H VHF/UHF rig to a King KMA28 audio
panel. It wasn't rocket science by any stretch of the imagination. In
fact, about four or five passive components in a small aluminum
enclosure is all it took. At some point I might want to add sidetone,
which will involve a few more components. But either way, it's
pretty simple.

-jav w6vms

Thanks for the kind words. So far as I know, there is no dedicated site to hams
in the air.

Now, start another thread of hate and discontent, I've been chastized mightily
(from people I don't know from Adam's Off Ox) that "aeronautical mobile" is
improper terminology when operating an amateur station on board a light
aircraft.

Since I can't find a definition of "aeronautical" in the FCC regs, can anybody
point me to where "aeronautical mobile" is limited to one class or category of
aircraft?

Jim


"MJC"
shared these priceless pearls of wisdom:

-Great thread, Jim. I've got a Yeasu FT-817 that I have been thinking of
-taking along with me in my yet to be completed RV7. I'm wondering if there
-is a web site that covers the use of Ham in the air more extensively?

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

Yeah, but then you've got to find a compliant A&P to sign it off {;-)

BTW, why not post the website of your installation. That has GOT to be the most
sanitary ham radio installation I've ever seen ... other than MINE, of course
{;-)


Jim



Javier Henderson
shared these priceless pearls of wisdom:

-
-I just got done adapting an IC207H VHF/UHF rig to a King KMA28 audio
-panel. It wasn't rocket science by any stretch of the imagination. In
-fact, about four or five passive components in a small aluminum
-enclosure is all it took. At some point I might want to add sidetone,
-which will involve a few more components. But either way, it's
-pretty simple.
-
--jav w6vms

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

No doubt about it...even though it is one of ... sniff ... THOSE intercoms {;-)


No, Ron, interfacing it through an intercom or audio panel removes a lot of the
folderol with interfacing it directly to the headset. However, you STILL need
to know the mic voltage and impedance levels (three different kinds in popular
use) for your parTICular ham rig.

Jim






"Ron Natalie"
shared these priceless pearls of wisdom:

-
-"Jim Weir" wrote in message
...
-
- The point is, there IS no ham radio standard, while the aircraft headset
- standard is quite well defined. You can't just hook the aircraft headset
into
- the ham rig on a PNP basis. You always wind up dicking around with voltage
and
- impedance shifters to make it play well.
-
-While putzing around with my aviation headset and my ham gear, I found that a
lot
-of the sins of bias voltages and impedences were covered up by placing my
sigtronics
-portable intercom between the aviation headset and the radio. After that,
it's just
-a matter of getting the connectors right and hooking up the PTT.
-

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