im an EE, but have never gotten into ham radio. Now, I have a reason!
Im going off roading in the california desert, and I'd like to be able
to communicate back home in San Diego. What band and equipment would
be the best (for both base and mobile) in order to communicate
reliably during the day? Or is this unreasonable?

On Tue, 28 Jul 2009 08:38:57 -0700, wrote:

im an EE, but have never gotten into ham radio. Now, I have a reason! Im
going off roading in the california desert, and I'd like to be able to
communicate back home in San Diego. What band and equipment would be the
best (for both base and mobile) in order to communicate reliably during
the day? Or is this unreasonable?

Someone will disagree, and we'll both learn something...

For getting through with just your equipment probably HF; on a truck it's
probably best to count on 20m, although at that distance 80m is
inherently 'better' for ground-wave daytime local-ish communication.

For getting through all the time, and assuming there's coverage, a
repeater. It won't get you all the way home unless there's a phone patch
available or an intertie. Since repeater clubs have widely varying
policies regarding furreners using their equipment, and the most common
arrangement is that anyone can use the repeater but only club members get
the magic finger ring combination to open the patch or the intertie you
may want to do some research.

For getting through all the time, with cost and effort rivaled by buying
a second rig to tow behind your main rig just so you can drive home, you
could set up for satellite operation. I'm not recommending this unless
you just plain want to have fun with it, but there you are.

Note that _all_ of these options except for the phone patch require that
you have someone with an amateur license and a matching radio on the
other end.

--
www.wescottdesign.com

In message , Tim Wescott
writes
On Tue, 28 Jul 2009 08:38:57 -0700, wrote:

im an EE, but have never gotten into ham radio. Now, I have a reason! Im
going off roading in the california desert, and I'd like to be able to
communicate back home in San Diego. What band and equipment would be the
best (for both base and mobile) in order to communicate reliably during
the day? Or is this unreasonable?

Someone will disagree, and we'll both learn something...

For getting through with just your equipment probably HF; on a truck it's
probably best to count on 20m, although at that distance 80m is
inherently 'better' for ground-wave daytime local-ish communication.

For getting through all the time, and assuming there's coverage, a
repeater. It won't get you all the way home unless there's a phone patch
available or an intertie. Since repeater clubs have widely varying
policies regarding furreners using their equipment, and the most common
arrangement is that anyone can use the repeater but only club members get
the magic finger ring combination to open the patch or the intertie you
may want to do some research.

For getting through all the time, with cost and effort rivaled by buying
a second rig to tow behind your main rig just so you can drive home, you
could set up for satellite operation. I'm not recommending this unless
you just plain want to have fun with it, but there you are.

Note that _all_ of these options except for the phone patch require that
you have someone with an amateur license and a matching radio on the
other end.

In the height of summer, in daytime, a maximum of around 300 miles would
be normal for 80m, but I think you'll be lucky reliably to get 500
miles. In fact, apart from very local stations, you could find 80m
totally dead between 11am and 2pm. Depending on ground conductivity,
groundwave goes out to around 20 miles before skywave really takes over.

If the sunspots on the sun had been a bit more active, and conditions on
40m had been 'normal', this band would have been a the definite
'general-purpose' choice. Groundwave is noticeably less than on 80m.
Typical communication range is 50 to 500+ miles.

On 20m, 100 miles is a bit close. You're unlikely to get reliable
communication at less than 250 or 300 miles. Groundwave is even less
than 40 - maybe only 5 miles.
--
Ian

Ian Jackson wrote:
On 20m, 100 miles is a bit close. You're unlikely to get reliable
communication at less than 250 or 300 miles. Groundwave is even less
than 40 - maybe only 5 miles.

I think you might be better off getting a CB. If only because when you need
help, you are much more likely to find someone nearby with the ability to
reach you or summon help.

If you want reliable communication over that terrain and distance, you
need a satellite phone. Every else ranges from "will never work" to
"probably will work most of the time", but not "will always work".

Of course the big question is why? Are you looking for help if you need it?
Are you just looking for a way "phone home"? Do you expect to have your
employer/customers call you for support?

Geoff.

--
Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM

In message , Geoffrey S.
Mendelson writes
Ian Jackson wrote:
On 20m, 100 miles is a bit close. You're unlikely to get reliable
communication at less than 250 or 300 miles. Groundwave is even less
than 40 - maybe only 5 miles.

I think you might be better off getting a CB. If only because when you need
help, you are much more likely to find someone nearby with the ability to
reach you or summon help.

If you want reliable communication over that terrain and distance, you
need a satellite phone. Every else ranges from "will never work" to
"probably will work most of the time", but not "will always work".

Of course the big question is why? Are you looking for help if you need it?
Are you just looking for a way "phone home"? Do you expect to have your
employer/customers call you for support?

Agreed. Unless there are any hills in the way, legal 27MHz CB should get
you a reliable 5 to 10 miles and, in the USA, I believe is a lot more
popular than elsewhere, and you could well be within range of other CB
users. And you don't need to pass an exam to get a licence (or even have
a licence). However, especially for real emergencies, it would be unwise
to rely on any ad hoc forms of radio communication. A satellite phone
would seem to be the way to go.
--
Ian

Thank you for all your excellent and useful responses!

To clarify my purpose:

1- I've been waiting for an excuse to get into Ham radio. I'm very
interested in learning RF circuitry (Experimental Methods in RF Design
is enroute as we speak), and this is a perfect opportunity, because I
actually need it! So Im up for getting a license.

2- The purpose of the radio is for emergency and for the cool factor
of being able to talk to home from 100+ miles away in the desert and
tell them about all the sand and rocks i see. Exciting for them!

3- The CB does sound better for emergency. So now, lets change the
purpose of the ham radio to just "cool of taking to home 100+ miles
away". And I will get a CB for emergency.

I had been leaning toward 20 meters since it has been described
everywhere as the DX band of choice. Now I see that it may not work
well so "close" as 100 miles. But wouldnt 80 meters have even more of
a problem? I am still not clear on which band to use...maybe some more
help please?

Ian Jackson wrote:
Agreed. Unless there are any hills in the way, legal 27MHz CB should get
you a reliable 5 to 10 miles and, in the USA, I believe is a lot more
popular than elsewhere, and you could well be within range of other CB
users.

From what I have read it is very popular in the EU which has far less
limitations on what you can do with it. There seems to be no practical
limitation on equipment and power, I often see articles about people
using 100 watt ham rigs, transmitting FM and packet data.

However, that's almost irrelevant, a 5 watt rig, even a 1970' handheld
with channels 9,14 and 19 will do, a 40 channel ssb rig would almost be
too much.

To keep it almost on topic, if you were to buy a long whip antenna, fold it
over, (run it horizontaly), and connect it to an autotuner, you could use it
for CB and NVIS ham communication.

NVIS is an interesting mode of communication, it uses vertical skywaves to
get wider range local communication from HF radio.

It may all be a moot point anyway. If you join a club they will probably tell
you what equipment you need. They probably standardized on something readily
available without a license such as CB's, FRS or GMRS, or possibly if they
thought no one would notice VHF marine radios (which are illegal to use
on land, but required for almost anything that floats).

Geoff.
--
Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM

wrote:
2- The purpose of the radio is for emergency and for the cool factor
of being able to talk to home from 100+ miles away in the desert and
tell them about all the sand and rocks i see. Exciting for them!

Ok, so that needs a general class or better license at both end. Do you
have a family member interested too?


3- The CB does sound better for emergency. So now, lets change the
purpose of the ham radio to just "cool of taking to home 100+ miles
away". And I will get a CB for emergency.

I had been leaning toward 20 meters since it has been described
everywhere as the DX band of choice. Now I see that it may not work
well so "close" as 100 miles. But wouldnt 80 meters have even more of
a problem? I am still not clear on which band to use...maybe some more
help please?


Look up NVIS, I described it in a post that crossed yours.

Geoff.


--
Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM

wrote:
Thank you for all your excellent and useful responses!

To clarify my purpose:

1- I've been waiting for an excuse to get into Ham radio. I'm very
interested in learning RF circuitry (Experimental Methods in RF Design
is enroute as we speak), and this is a perfect opportunity, because I
actually need it! So Im up for getting a license.

2- The purpose of the radio is for emergency and for the cool factor
of being able to talk to home from 100+ miles away in the desert and
tell them about all the sand and rocks i see. Exciting for them!

3- The CB does sound better for emergency. So now, lets change the
purpose of the ham radio to just "cool of taking to home 100+ miles
away". And I will get a CB for emergency.

I had been leaning toward 20 meters since it has been described
everywhere as the DX band of choice. Now I see that it may not work
well so "close" as 100 miles. But wouldnt 80 meters have even more of
a problem? I am still not clear on which band to use...maybe some more
help please?


I guess a cellphone is out of range? You're not going to have reliable
"100+ mile coverage" with a CB or even with ham radio on a simple "push
button to talk" basis unless both parties are licenced and have some
knowledge about how radio works.
You need one of those 'illegal' phones like they sell in Brasil

Sat phones do this type of thing, not inexpensive though. Some of those
Brasilian phones illegally utilise military frequencies via US-DOD
satellites!

May I recommend a digital camera, 99 cent spiral bound notebook and a
pencil as the latest and least inexpensive technological breakthrough?

-Bill

In message , Geoffrey S.
Mendelson writes
Ian Jackson wrote:
Agreed. Unless there are any hills in the way, legal 27MHz CB should get
you a reliable 5 to 10 miles and, in the USA, I believe is a lot more
popular than elsewhere, and you could well be within range of other CB
users.

From what I have read it is very popular in the EU which has far less
limitations on what you can do with it. There seems to be no practical
limitation on equipment and power, I often see articles about people
using 100 watt ham rigs, transmitting FM and packet data.

Not legally! In the UK, CB is limited to 4W of FM. Most other European
countries are very similar, although some do also allow SSB (and maybe
even AM?).

However, that's almost irrelevant, a 5 watt rig, even a 1970' handheld
with channels 9,14 and 19 will do, a 40 channel ssb rig would almost be
too much.

A handheld on a whip antenna might get you 20 miles but, more likely, 2.

To keep it almost on topic, if you were to buy a long whip antenna, fold it
over, (run it horizontaly), and connect it to an autotuner, you could use it
for CB and NVIS ham communication.

NVIS is an interesting mode of communication, it uses vertical skywaves to
get wider range local communication from HF radio.

I don't think that you get much NVIS on the higher HF amateur bands.
However, you certainly do on 80m, where (at least in the UK) most
horizontal antennas are rarely much higher than 30' or 40'. The RF goes
straight up, and (if there's anything up there to reflect it back)
straight down again. In summer daytime, the RF tends to get absorbed by
the low-level D-layer (rather than reflected), so ranges are short, and
signal levels poor. This disperses at night, and the much-higher F-layer
allows a longer-range 'bounce' - even for signals with high-angle
radiation. Most really long distance stuff is via vertical antennas,
which are notoriously poor for relatively short-distance working (beyond
groundwave range). However, above around 5 or 6MHz, high-angle signals
tend to go straight through the ionosphere, and are lost for ever.

It may all be a moot point anyway. If you join a club they will probably tell
you what equipment you need. They probably standardized on something readily
available without a license such as CB's, FRS or GMRS, or possibly if they
thought no one would notice VHF marine radios (which are illegal to use
on land, but required for almost anything that floats).

I don't want to be a 'misery-guts', but I would be a bit circumspect
about the idea of 'getting into amateur radio' because you want to be
able talk to the folks back home when you are on holiday. If you have no
previous experience of the characteristics of the amateur bands,
equipment, antennas etc, it's highly unlikely that you will be very
successful. To avoid disappointment, it might be best to stick to
tried-and-tested technology. On the other hand, why not simply forget
about the folks at home, enjoy your holiday, and take up amateur radio
when you get back!
--
Ian