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Re: Inner city sat station



Hi,
I have a similar situation.  I live in an apartment right above the nosey 85
year old landlady.  I have worked 69 QSOs on AO-10, FO-20, FO-29 and RS-12 in
the last several months.  Here's what I do.  From the description of your
situation, you can do MUCH better.

2 meters:
I use a quarter wavelength mag mount on the balcony for most of my uplinks on
the FO-20/29 uplinks.  I've also used it as the downlink for AO 10 for a
couple QSOs!  It works pretty well, but is shielded by the building for
anything except eastern passes.  Nevertheless, it gets me on the band.  

For most of my AO-10 QSOs and the really shallow LEO passes (east only) I bolt
a 4 element yagi to the balcony railing and hold the other end up with rope.
This allows me to adjust the elevation angle.  This antenna has a beamwidth of
about 60 degrees, so I get a good portion of the middle of the LEO pass.
AO-10 is slow enough to allow adjustment only every half hour or so.

435 MHz:
I use a home made 8 element Quagi scaled up from 432 from the ARRL antenna
handbook.  I mount it on a camera tripod and usually keep it in the living
room for ease of access at the expense of some signal loss.  This works pretty
well on the FO birds.  For AO-10 uplink, I usually put it on the balcony since
I need more signal and have to adjust it less.

10M:
I put up a dipole (actually a 20M one) along the edge of the ceiling in my
"radio room".  It's so close to the radios, that it picks up the
microprocessor noise from the 2M rig (FT-736) so it's pretty tough to do mode
A, but if it were located further away or I used a different rig, this would
probably not be a problem.  

Now if I had your luxurious accommodations (and lots of time, money and
radios), I'd put up a small push-up pole in the back yard near the radio room
or else a small tripod on the roof.  On this I'd mount an az-el rotor like
shown in the ARRL books etc. and a 2M and 435 crossed yagi array.  A 10M
dipole or two would complete the set-up.  This would allow access to all the
mode A,B,and J birds.  I'd probably keep the antenna height just slightly
above the peak height of the roof if possible to keep them out of sight from
the street to minimize neighbor problems.

If you're just starting (I don't think you mentioned your experience level
with the satellites), I'd recommend monitoring the downlinks first.  Any 10M
rig and a hunk of wire will pick up the beacons and you'll learn about doppler
and where to tune, decode the beacon etc.  

Next I'd probably put up a 2M vertical (ground plane, J-pole, dipole, etc.)
and a 10M dipole and start with RS-12.  You can put that up in a couple hours
and get on the satellites first and upgrade the station from there as time and
money permits.  The radios you have available will obviously greatly affect
you decision.  Whether you start with FO-20 and 29 or RS-12, you should be
able to get on the air with very little time or effort.

If you are new to the satellites, I'd also go to www.amsat.org and read the
introductory articles.  The article "Working the EasySats" is a really good
introduction.  Several of the others and the "articles" sections have a lot of
great information that will answer most of your questions.  The ARRL Handbook,
Antenna  Book, and the Satellite handbook all have a wealth of information
too.

Feel free to ask (via direct e-mail) if you have any questions about the
above.

73,
John, KJ6HZ



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