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Re: An V/U antenna for LEOs?



On Sun, 15 Oct 2000, Christopher Cox wrote:

> Bob,  I know you mean well. It would seem that your generalizations are
> getting you into trouble.

I don't think it is  my generalizations, but people's reading sentences
out of context and not thinking in terms of what is being discussed.

> I am sure that an OSCAR home station can beat the pants off of a HT with
> quarter wave whip. 

So do I.  But that was not what we were talking about.  I was  comparing a
1/4 wave whip on the roof of a car which will outperform ANY HOME STATION
WITH A LONG RUN OF COAX TO AN OMNI ANTENNA.  Caps for emphasis, not
yelling, hi hi..

> Just the same, a standard terrestrial two meter station would have large
> problems working the LEO's, and the user would be better advised to use
> his HT.

Yep, that was the point I was trying to make.  Others missread it...

> About APRS. You seem to be pushing hard promoting its use. 

I am pushing REAL-TIME UI packet digipeating.  Notice that in almost all 
of my postings I try to say APRS or UI digipeating...  I dont care what
people digipeat, as long as it is UI , REAL TIME and not connected.  It is
proven that connections are totally inneffecient in the many-to-one
mission of a satellite..  ALso, all the interest in the VOice FM birds
demosntrate that fundamental to the JOY of HAM radio is WORKING A REAL
LIVE PERSON AT THE OTHER END, not a BBS.....

> I sort of look at [APRS] as a Store Forward Text Paging system, which
> given all the short comings of LEO's is great. I personally have a problem
> with what the APRS protocol was intended for. I do not want to tell others
> where I am at all the time. 

Then you haven't considered the APRS position ambiguity feature.  You can
indicate you position to the nesrest 60 feet, 600 feet, 1 mile, 10 mile
or 60 miles.  Almost all hams announce their position to one of these
ranges when they are in any QSO...  IE, Im in Baltimore (+/- 10 miles)
or Im in Maryland (+/- 60 miles)...  Only report your position to the
degree you want.  Actually there is one more degree which is to the
nearest 600 miles, which is based on callsign PREFIX.  If you do not want
to be identified as being in the USA, then you can change your call...

> We already have enough people intruding into
> our privacy, willingly or not. Perhaps they should rename the protocol. I
> for one am not going to place a GPS on myself and spout out here I am. I
> distrust the latest initiative by the United States Government to place GPS
> into all of our cell phones.

Then dont use them.  I dont own one and have no intention to.  I have HAM
radio and find it my challenge to try to find better ways to use it...

> In short, while understanding your zeal for technology, try to temper your
> enthusiasm and look at some of these issues through the eyes of
> others...... :-)

Thanks.  Maybe others should be a little more generous when trying to read
what others write and give them the benefit of the doubt too...  THinking
about new ways to use our radios is far more productive than trying to
nit-pick what others say.

Your points are well taken.  I often omit all the mumbo-jumbo necessary to
make my wiritings immune to nit-picking, because if I put in all the
added caveats and mitigating sentences with everythig I say, then the
length DOUBLES and then nobody wants to read it.  I know I dont like long
messages..

For those that missed it.  The CASE above assumes NO PREAMPS.  Put in a
PREAMP and it all changes too.  But again, that is not the point and not
what we are talking about...  We are talking about how the RF reaching
your HT or your CAR roof in the center of a LEO Satellite pass is as GOOD
as the signal reaching any other antenna anywhere.  And WITHOUT all of  
these things:

  Low loss coax
  Preamps and remote pre-amp power
  Beams
  AZ/EL mounts
  AZ/EL position indicators
  AZ/EL rotor systems
  AZ/EL computer controls.

None of these are needed IF you use a few feet of coax and a handheld
antenna.  That is what I am trying to get across to all the NON-SATELITE
STATIONS.  Face it, 99% of HAM oeprators are not into Satellites because
the THINK that all that stuff is required.  We do ourselves a disservice
by always insisting that it is.

Satellite ops with an OSCAR station should IGNORE my mission.  THey
already know what it takes to work the birds.  I am talking to the newbee
that wants to get started and my not have thought about the implications
of a terrestrial OMNI station as being exactly the wrong station for a
satellite pass...

de WB4APR, Bob



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