Judy and I did further testing of 1/4 wave and 5/8 wave antennas for 2
meters on her vehicle using the ICOM IC-7000 at 50 watts out. The base
station continued to be the 30 foot high homebrew J-pole and now has 100
watts out from the ICOM 746 Pro. The mobile antennas were only mag
mounts, but t
Hi Rick,
>
> The numbers for the models seem very optimistic. Normal gain for J-pole
> (theoretical) can not be more than a dipole, since the antennas is an
> end fed dipole with the "Q" section for matching. This means at most
> 2.14 dBi, but maybe you are experiencing some ground gain which you c
Hi Skip,
The numbers for the models seem very optimistic. Normal gain for J-pole
(theoretical) can not be more than a dipole, since the antennas is an
end fed dipole with the "Q" section for matching. This means at most
2.14 dBi, but maybe you are experiencing some ground gain which you can
ge
Rick,
> Skip,
>
> Realistically, the 5/8 wave will be maybe around the gain of a dipole. I
> would use 2 dBi, maybe 3 dBi at the most. I don't think there are any
> 5/8 wave verticals that can do much better than that and some antenna
> gurus point out that they can perform worse than half wave an
Skip,
Realistically, the 5/8 wave will be maybe around the gain of a dipole. I
would use 2 dBi, maybe 3 dBi at the most. I don't think there are any
5/8 wave verticals that can do much better than that and some antenna
gurus point out that they can perform worse than half wave antennas. I
have
CTED]>
To:
Sent: Thursday, November 27, 2008 8:19 PM
Subject: Re: [digitalradio] Re: How Can We Push HF Emcomm Messages to the
Field?
> >
>> If the signals are in the marginal range, how do you do the coordinating
>> between the stations? To date, we have been able to
>
> If the signals are in the marginal range, how do you do the coordinating
> between the stations? To date, we have been able to use a cell phone.
>
> How do you calculate the error rate (such as the 6% mentioned)?
We send 50eroids.(..). Anything
that
Very good information, Skip,
If the signals are in the marginal range, how do you do the coordinating
between the stations?
How do you calculate the error rate (such as the 6% mentioned)?
If I understand this correctly, the test was between a 5/8 vertical to
quad for vertical polarization vs.
Hi Rick,
>
> Have you found that DominoEX is the best overall digital mode for FM? I
> know that PSK modes can have doppler errors from aircraft, but otherwise
> seem pretty good for weak signal.
Yes, definitely! DominoEx is a frequency shift keying mode, not a phase
shift mode, but doppler probl
Skip,
Have you found that DominoEX is the best overall digital mode for FM? I
know that PSK modes can have doppler errors from aircraft, but otherwise
seem pretty good for weak signal.
Your point is well taken that many of the hams who participate in public
service activities, may tend to be t
ed
VE3FAL
-Original Message-
From: digitalradio@yahoogroups.com [mailto:[EMAIL PROTECTED] On
Behalf Of Charles Brabham
Sent: Wednesday, November 26, 2008 6:22 PM
To: digitalradio@yahoogroups.com
Subject: Re: [digitalradio] Re: How Can We Push HF Emcomm Messages to the
Field?
One obvious
No hard feelings, Howard!
Your passion for the hobby is appreciated, and many of us have hit the Send
key, wishing immediately afterward that we had not!
Regardless, I thought many of your points were well made and bared
repeating.
73, Skip KH6TY
NBEMS Development Team
- Original Messag
typing, my vision is not good today and I'm a hunt 'n peck typist.
73 DE Charles Brabham, N5PVL
- Original Message -
From: John Becker, WØJAB
To: digitalradio@yahoogroups.com
Sent: Wednesday, November 26, 2008 4:41 PM
Subject: Re: [digitalradio] Re: How Can We Push
In this county you can sum up the biggest problem in
one word "manpower". Within my zip code there is
3 hams living in town.
One is up in the years and has not been on the air in
years as well as to weak to do much.
As far as the other 2, one is chief of police. The other
is #2 in command on
ay, November 26, 2008 3:38 PM
Subject: Re: [digitalradio] Re: How Can We Push HF Emcomm Messages to the
Field?
> Hi Howard,
>
> If you respond to someone's response to a question, with asking
> questions of your own, then it might be reasonable for some to respond
> as Skip did
Howard,
First of all, there is no need to shout! My old eyes are still fine for
reading without your using caps! :-)
This group is for the purpose of discussion about using digital modes in
amateur radio, all opinions are welcome, and nothing should not be held
against a person for posting a c
Hi Howard,
If you respond to someone's response to a question, with asking
questions of your own, then it might be reasonable for some to respond
as Skip did. It seems reasonable to me considering you asked "Is the
volunteer out of VHF range?" You also asked about setting up something
in the b
This is something that would likely be more at home at the HFDEC
yahoogroup that discusses disaster and emergency communications but lets
look at some of the practical aspects.
Distance was not specified, but it would be rare to send someone out at
night, under dangerous conditions, in unfamili
PM
To: digitalradio@yahoogroups.com
Subject: RE: [digitalradio] Re: How Can We Push HF Emcomm Messages to
the Field?
And further, this thought should be considered as VHF FM, or VHF SSB? In
a
base/mobile or mobile/mobile environment, SSB on VHF works over much
greater
distances.
With voice
The last time I got into something like this I was called
(all be it direct reply) a fool.
What works for you in the large city may not work for me
in the rural area with hills all around.
In the floods this spring I at times had the only HF mobile
rig in the county.
Conditions just now are at night hostile to even NVIS. We sometimes eke
out ground wave between MARS members here with vertical antennas below --
well below -- 3.5 MHz. Some nights I'd like something below 1.8!
Nevertheless, my mobile setup, when I have it installed, covers 160-440.
MARS freq
FWIW, in the response to Gustav
It was known that Region 4 Resources would be deploying into the area in
support of the Southern Baptist Disaster Relief Organization.
Days ahead, info was exchanged on formal net operations in that area to
allow members from Region 4 to check propagation and
Howard,
We already achieved successful, error-free, VHF communication (with no
repeated blocks) using NBEMS software over a 70 mile path in flat country
between two 50 watt FM transceivers, one with a 7.5 dBi antenna at 10 feet
off the ground and the other with a 7.5 dBi antenna 25 feet off the
And further, this thought should be considered as VHF FM, or VHF SSB? In a
base/mobile or mobile/mobile environment, SSB on VHF works over much greater
distances.
With voice communications, VHF SSB benefits from having flutter resulting in
the desired signal amplitude going up and down, while t
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