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Re: Saying "hi" on AO27 gets my goat!



Mike,

"Michael P. Olbrisch" wrote:
> I am simply graduating to a better station.  Going to use a more "reliable"
> link.  Got a pre-amp for the mast.  Got a big antenna.  Working on mast
> mounting the amp, so the full power goes straight to the antenna, not
> lost in the coax on the way up.  160 watts @ 15 dB gain could potentially
> be more than 3KW ERP, depends on how short I can keep the coax.  The
> big problem was getting a low loss 12vdc source to the tower.  Well, it
> was easier to run 120vac up there and put the P/S up there too.  Less
> I2R loss that way.  I am simply doing my best!
> 
It sounds like you are assembling a world class Oscar station.  3 kw
erp?  ... more later

 
> > On a Saturday afternoon, during a mid continent pass of AO27, the
> > reliable link would include a gain antenna
> 
> No dispute there.  I'm working on it.  Still need a fiberglass cross-boom.
Bill, W0OQC suggests going to a home improvement store and buying a rake
affixed to a fiberglass handle.  You might find one on sale this time of
year.  Remove the rake, and you'll have a fiberglass cross boom.  Of
course, with 2, 2 meter antennas, and a 70 cm yagi, you might have to
engineer a different arrangement.

> 
> > Why are they successful?
> 
> The good-old-boy network at work.  I have successfully heard my
> "marginal" 50 watts on a J-pole several times.  Just partial call
> sign because the good-old-boys just talked right on top of it.
> Jim-Bob checking on Billie-Bob's cat or something.  I know that
> 50 watts on a Tri-band J-pole would work if there wasn't so much
> crowding on the sat.  But it won't compete with 50 watts on a
> 10 element beam.
Nah.  Good-old-boy network?  I don't think one exists in the context you
claim.  Most of the big stations leave gaps in there for the smaller
stations.  I can see why an operator frustrated by inability to get into
the bird might arrive by that rationale.  I used to try working AO27
with a Ringo antenna, and I imagine a JPole is at least as ineffective.

> > By the way, listen for me on the mid continent pass today.  I
> > will be HT portable on Sanibel Island, in a rare grid: EL86.
> 
> Thanks for the offer, and I surely do need that grid.  But at the
> moment, all I have is my marginal Tri-band J-pole.  So why bother?
Mike, I was really hoping you'd be listening with your HT. (It would
work better than your base station and JPole).  I managed to work
several stations, during a Sunday, mid continent pass, on Labor Day
weekend!  I even worked a couple of other operators using HTs and QRP:
N3ZLL, and N2YQP.  So much for the good-old-boy network, unless they
just "let" me in!  :-)

> 
> The GOOD side of this is that by the time I am finished, I should have
> one really kick-ass station for satellite use.  Gotta spend all that
> money on something, and the 160 watt amp was only $100, great
> deal, couldn't pass it up!  A pair of 2m 22 element KLMs and a power
> divider appeared in good condition.  Nice things happen to nice
> guys hi hi.  The 40 ele 70cm was a bit more costly, but still not
> too bad.  I had the rotors from last year already.  All it takes it
> time and money.
WOW!  A very nice station!  I have a KLM 22C and a 40CX.  They work
great.  The polarity switchers will make all the difference on ALL the
birds, I'm sure you'll find.

I think the 22C has a claimed 15 dBdi gain figure.  A pair of them
properly power divided should show an 18 dBdi gain figure.  If you
figure a 1.5 dB loss in your coax, with a 160 watt PEP output, your EIRP
will be somewhere around 38.5 dBW, and your ERP should be a whopping
7,147 watts ERP! Be careful with that power; you might just go down in
history as the Farthest West Ham in West Texas to start a grass fire,
with his ham station!

> 
> In closing, I would like to point out that I am not whining, that you
> brought up the subject, and that I am following your advice very
> closely, building a better station.  If one thing has been proven
> out here, it is still  "If you can't join em, beat em."
Yes you were. :-)  I am REALLY looking forward to working you on all the
birds!  Your station will be a true contender.  For what it's worth, I
seldom use my 2 meter amplifier, but regularly use a 70 cm amp while
working AO10.  If you get a chance to trade, take it.  With that much
gain on 2 meters, there isn't a bird up there you will need more than 10
watts on 2 meters.  With 18 dBdi gain, you'll regularly work FO20 with a
watt.  I run between 1 and 8 watts on the LEOs with 15 dBdi.  

Hey, I'll bet we can work each other on RS15!  That can be a fun bird,
and it does require an amp, USUALLY.  Now I have to scramble and better
my marginal 10 meter downlink antenna.  My homemade turnstile just isn't
performing as well as I'd hoped, and not at all below 15 degrees to the
east, and 30 degrees to the west. (The house is in the way!)

> 
> Thanks for all the good advice.  Have a great Sunday.
You're welcome, and let me know when you're ready.  I would be pleased
to be your first contact on one of the birds.  My favorite is FO20.

73, Mike in Fort Myers, FL
                                       __\/__ 
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   |||   | |   * Mike Gilchrist - KF4FDJ ..... AMSAT Area Coordinator *
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