Folks

So I'm thinking about emergency communications and it seems to me that
an 800 Mhz Yagi antenna would be useful. I have one of those old
Motorola bag phones which I use when travelling in rural Alberta.

It works nice especially when on a 3' mag mount antenna on the vehicle
roof but it seems to me a Yagi up 20' might be useful at times.

Tony

Tony VE6MVP writes:

Folks

So I'm thinking about emergency communications and it seems to me that
an 800 Mhz Yagi antenna would be useful. I have one of those old
Motorola bag phones which I use when travelling in rural Alberta.

It works nice especially when on a 3' mag mount antenna on the vehicle
roof but it seems to me a Yagi up 20' might be useful at times.

Just try it. These things don't cost much, do they? Although you
already have a decent antenna.

Compared to the built-in antenna of a typical cell phone, it will make
a tremendous difference.

Here in Norway we have GSM, 900 MHz in rural areas. The signal is very
poor at our summer house. So we bought a 40$ 9 el. Yagi at a hardware
store and put it in a tree, may be 15 ft up. It's supposed to have 10
dB gain, but it comes with 33 ft of RG-58, so we lose more than half
the gain on the way. However, the built-in antenna of most cell phones
is unbelievably bad, and getting the antenna higher up makes a
lot of difference at our location. I went from 0 bars to 5.

The coax is marked "low loss" with nice, friendly letters. I guess
that's what does the trick :-)

73
Jon

Jon, just think of how many bars you would have had the cable been
marked ULTRA LOW LOSS...
denny / k8do

On 07 Nov 2006 11:22:53 +0100, LA4RT Jon wrote:

The coax is marked "low loss" with nice, friendly letters. I guess
that's what does the trick :-)

chuckle

Tony

Tony, look in the ARRL Antenna Handbook... There will be short yagi
designs for UHF... A Quagi would work well and be easy to match, but
not as handy to stow away...I suggest 5 elements as the most bang for
the buck between complexity and performance... Just scale to your
frequency... Use a small aluminum tube for the boom, and bare welding
rods for the elements... Put a decent piece of RG8 or LMR400 on it and
it should play well...

denny / k8do

Tony VE6MVP wrote:
Folks

So I'm thinking about emergency communications and it seems to me that
an 800 Mhz Yagi antenna would be useful. I have one of those old
Motorola bag phones which I use when travelling in rural Alberta.

It works nice especially when on a 3' mag mount antenna on the vehicle
roof but it seems to me a Yagi up 20' might be useful at times.

Tony

Is there an easy way of coupling the phone to the coax?

Alan
WN4HOG

--
Windsurfing Club: http://www.ibscc.org


"Denny" wrote in message
oups.com...
Tony, look in the ARRL Antenna Handbook... There will be short yagi
designs for UHF... A Quagi would work well and be easy to match, but
not as handy to stow away...I suggest 5 elements as the most bang for
the buck between complexity and performance... Just scale to your
frequency... Use a small aluminum tube for the boom, and bare welding
rods for the elements... Put a decent piece of RG8 or LMR400 on it and
it should play well...

denny / k8do

Tony VE6MVP wrote:
Folks

So I'm thinking about emergency communications and it seems to me that
an 800 Mhz Yagi antenna would be useful. I have one of those old
Motorola bag phones which I use when travelling in rural Alberta.

It works nice especially when on a 3' mag mount antenna on the vehicle
roof but it seems to me a Yagi up 20' might be useful at times.

Tony

"Alan" wrote in message
m...
Is there an easy way of coupling the phone to the coax?

I have observed that two of my family's (various) phones have concealed coax
fittings. Look for any bit of peelable/liftable plastic trim on or near the
top of the phone that might be covering such a jack.

Dunno what the connector series would be -- there are more different kinds
than I can name by eye.

I think I may have observed a coax fitting on the base of one phone. This
would be for a unified vehicle adapter, where you slap the phone into a
cradle and get power, RF and audio all at once.

I hope this helps.

On 7 Nov 2006 04:31:37 -0800, "Denny" wrote:

Tony, look in the ARRL Antenna Handbook...

Interesting idea. I just received the 16th ediition which I got from
someone on Ebay. I

Put a decent piece of RG8 or LMR400 on it and
it should play well...

That LMR400 is fairly stiff stuff. The biggest problem would be
locating the end that fits on the Motorala bag phone especially with
LMR 400.

I have no idea what kind of end it is but I'm sure a commercial radio
shop can tell me.

Tony

Get LMR-400 Ultraflex. Much more flexible.
Adaptor cords are available for most any phone from various suppliers.
Try google on "cell phone antenna cord"

Bob



In article ,
Tony VE6MVP wrote:

On 7 Nov 2006 04:31:37 -0800, "Denny" wrote:

Tony, look in the ARRL Antenna Handbook...

Interesting idea. I just received the 16th ediition which I got from
someone on Ebay. I

Put a decent piece of RG8 or LMR400 on it and
it should play well...

That LMR400 is fairly stiff stuff. The biggest problem would be
locating the end that fits on the Motorala bag phone especially with
LMR 400.

I have no idea what kind of end it is but I'm sure a commercial radio
shop can tell me.

Tony

On Wed, 08 Nov 2006 13:21:12 -0500, Bob Dixon wrote:

Get LMR-400 Ultraflex. Much more flexible.

Good point. I've heard of that stuff in the past but had forgotten
about it.

Adaptor cords are available for most any phone from various suppliers.
Try google on "cell phone antenna cord"

Thanks, Tony