"Michael Coslo" wrote in message
...


I think you are both correct. While the purpose is emergency preparedness, the
format seems rather contest like. Keeping score, different classes, posting
the scores in QST.
- 73 de Mike N3LI -


Must not be a contest then, because contest scores don't get posted in QST under
current management.

73, de Hans, K0HB

On Tue, 17 Jun 2008 12:30:29 EDT, Jeffrey D Angus
wrote:

I thought the purpose of Field Day was to serve as a training
ground for emergency preparedness. And a time to experiment
with new techniques and technology in an "emergency" setting
without it being a "real" emergency.

My sole interest in 80 meters is for EmComm data modes, where NVIS is
the desired mode. I hope that my (inefficient) dipole will do what I
want.....
--

73 de K2ASP - Phil Kane

From a Clearing in the Silicon Forest
Beaverton (Washington County) Oregon

e-mail: k2asp [at] arrl [dot] net

Phil Kane wrote:
On Tue, 17 Jun 2008 12:30:29 EDT, Jeffrey D Angus
wrote:

I thought the purpose of Field Day was to serve as a training
ground for emergency preparedness. And a time to experiment
with new techniques and technology in an "emergency" setting
without it being a "real" emergency.

My sole interest in 80 meters is for EmComm data modes, where NVIS is
the desired mode. I hope that my (inefficient) dipole will do what I
want.....

Only it really isn't inefficient - at least not because of it's
radiation pattern.

I'm curious though, what data modes do you use on 80? I do PSK there,
but are you doing handshaking and error correction? This time of year
could be taxing on that.

We can spin this into an other thread if you like.


- 73 de Mike N3LI -

On Tue, 17 Jun 2008 12:30:29 -0400, Jeffrey D Angus wrote:
Dick Grady AC7EL wrote:

However, the object of Field Day is to contact as many
stations as possible.

I thought the purpose of Field Day was to serve as a training
ground for emergency preparedness. And a time to experiment
with new techniques and technology in an "emergency" setting
without it being a "real" emergency.

Y'know, I've heard both arguments for a very long time. IMHO you're both
wrong.

Field Day is a party.

(in the non-alcoholic, family reunion sense)

In news Doug Smith W9WI typed, for some strange, unexplained
reason:
: On Tue, 17 Jun 2008 12:30:29 -0400, Jeffrey D Angus wrote:
: Dick Grady AC7EL wrote:
:
: However, the object of Field Day is to contact as many
: stations as possible.
:
: I thought the purpose of Field Day was to serve as a training
: ground for emergency preparedness. And a time to experiment
: with new techniques and technology in an "emergency" setting
: without it being a "real" emergency.
:
: Y'know, I've heard both arguments for a very long time. IMHO you're
: both wrong.
:
: Field Day is a party.
:
: (in the non-alcoholic, family reunion sense)

Eh..? Whaddya'mean, non-alcoholic..?! ;-)

73 Ivor G6URP

"Doug Smith W9WI" wrote in message
news

Field Day is a party.

(in the non-alcoholic, family reunion sense)

How do you survive a family reunion without alcohol?

Beep beep,

de Hans, K0HB

Bill,

NVIS antennas are in fact desirable in some applications, where you wish to
communicate only with stations nearby, say out to about 250 miles. I can see
them useful in emergency communcations scenarious to get good HF coverage of a
local disaster area, or for use on a section traffic net, or other similar
"local" communications needs. In a "contest" situation like Field Day they'd be
tactically useful to have in your bag if your station was located in a high
population density area with a lot of nearby stations like the east coast
corridor, so that you'd somewhat avoid having a skip-zone, especially if the low
bands (40 and 80) "go long" at night.

73, de Hans, K0HB

Bill Horne writes:

The goals with NVIS are twofold:
- Avoiding nulls in local area coverage.
- Eliminating distant noise and QRM. If you're, after local coverage,
you also want that.

Local is a relative term. If the reflective layer is 200 km up, ranges
up to 480 km have a takeoff angle of 40 degrees or higher. A dipole a
quarter wave up above average ground is less than 2 dB down at that
elevation. At very low heights, the dipole is 3 dB down at 45
degrees. (It also radiates just a small fraction of the power you feed
it.)

As to why this would be the best design, it won't be for winning the
contest! Your brother may have another goal, like simply wanting to
test the design.

By the way, only part of the power going down is lost. The rest is
reflected. How much depends on height and ground characteristics.

73
LA4RT Jon

Thanks for reading this. I've just been through a very confusing
antenna trial, and I'd really appreciate some info from hams who know
more about them then I.

My brother, W3TDH, called me up yesterday and asked me to help test
some 80 and 40 meter antennas that his club is preparing for field
day. He told me that the club is going to serve their target coverage
area by using two dipoles, spaced 1/2 wave apart and fed in phase, so
as to maximize NVIS (Near-Vertical Incidence Skywave)radiation.

I'm not arguing with the design: antennas spaced 1/2 wave apart and
fed in phase always have maximum radiation at right angles to a line
bisecting both antennas. Ergo, two dipoles, horizontally mounted,
etc., will indeed produce their maximum radiation straight up and
down.

My question is: why would that be the best design? I thought that NVIS
radiation was a byproduct of having a radiator less than 1/2 wave
above the ground, and that it wasn't to be sought after, but rather
avoided. Leaving aside the losses due to 1/2 the power pointing
straight down, why would an antenna on 80 or 40 meters be most
effective by radiating almost straight up? Wouldn't the coverage be
improved by phasing the antennas so as to maximize radiation toward
the horizon?

73,

W1AC

--
Bill Horne, W1AC

(Remove QRM from my address for direct replies.)

"Bill Horne" wrote in message
t...
Thanks for reading this. I've just been through a very confusing antenna
trial, and I'd really appreciate some info from hams who know more about
them then I.

My brother, W3TDH, called me up yesterday and asked me to help test some
80 and 40 meter antennas that his club is preparing for field day. He told
me that the club is going to serve their target coverage area by using two
dipoles, spaced 1/2 wave apart and fed in phase, so as to maximize NVIS
(Near-Vertical Incidence Skywave)radiation.

I'm not arguing with the design: antennas spaced 1/2 wave apart and fed in
phase always have maximum radiation at right angles to a line bisecting
both antennas. Ergo, two dipoles, horizontally mounted, etc., will indeed
produce their maximum radiation straight up and down.

My question is: why would that be the best design? I thought that NVIS
radiation was a byproduct of having a radiator less than 1/2 wave above
the ground, and that it wasn't to be sought after, but rather avoided.
Leaving aside the losses due to 1/2 the power pointing straight down, why
would an antenna on 80 or 40 meters be most effective by radiating almost
straight up? Wouldn't the coverage be improved by phasing the antennas so
as to maximize radiation toward the horizon?

73,

W1AC

--
Bill Horne, W1AC

------------

It's just a W.A.G., but most of the old publications reflected the culture
of the time and the culture in those days was oriented to working DX, not
locals. Today, I enjoy talking out to several hundred miles much more than
speaking to someone a continent or two away who is restricted (many times)
as to what they can or cannot say by their government. Then throw in foreign
accents, my aging hearing, etc., and one understands why speaking with my
fellow Americans is a much more pleasant experience - most of the time. I
mean no offense to foreign amateur radio ops. I enjoy speaking with them
too, when in a relaxed, non competitive atmosphere.

Ed, NM2K