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RE: Ed's startup response

Welcome to AO-40. It is a fun bird with lots of potential.
My Rig:
I have a 60 cm alum dish with a miller patch also. I am getting it ready to
use as a portable. I have built a 2&1/2 turn L-Band helix feed to mount
around the 2.4Ghz patch. Thus, I'll be L-band up link and 2.4Ghz down. The
60cm dish is as small as you dare use, since the high power transponder went
west. It does work well enough to get you on. Be sure you have a HOT
converter since you  are looking for signals right down near the noise.
For the home QTH Station, I use a 1.2m offset Channel Master dish with a
Miller Patch feed. It is GREAT. I get the beacon at S7-9 and even +5-10 with
squints in the area of 3-5 degrees.
I use an Icom 910H just like yours and I love it. It is a great radio. A
couple of things that make it perform better: When you pick up the beacon,
start reducing the RF gain control so you operate with Minimum RF gain.
Next, shift the IF band pass up (I run it at about 1-2PM). This narrowing of
the bandpass further gains you S/N and makes it more armchair copy. I use a
VU meter on the audio output so I can actually watch the noise /vs/ audio
level. With the 1.2m dish and my UEK 3000 downconverter, I get a noise level
of -25-30db below 100% modulation of the beacon.
NOVA is great, after you get the hang of it. There are setups hidden within
drop menus that take a while to find. The fact that you load new Keps on
line is GREAT... I use NOVA and the Kansas City Tracker board to run my
rotors (G-5500). Works great. I then decode the beacon by running the audio
output from a second receiver (Yaesu FT-100D) to the audio input of a second
computer sound card. On that box I run AR4ORcv. which decodes the beacon
date. I use that program to run the FT-100 Mic up/down to keep the receiver
on frequency for the complete pass. Also works great.
Uplink, I use the 910 into a 120watt 70cm brick and a 30 element M2 crossed
yagi or the 910 on L-Band into an 80 watt brick and a 15 turn Helix antenna.
70cm is best.

You must have a clean shot at the bird, especially with a 60cm dish. No
trees etc.
I do not receive until about 3-5 degrees above the horizon.
Make sure your Keps are up to date. Just download the new ones on the
Internet with NOVA.
Pick an orbit with a high elevation angle and a good squint angle (you'll
have to turn on the Squint and MA settings in Nova) and then go fishing for
it using the az/el supplied by NOVA. Once you get it rock your rotors back
an forth to be sure the actual peak level is where NOVA tells you it is.
Some times we don't set our antennas completely level for 0 degrees and have
not used the north star or the like to really point North. This calibration
is important. You can use the sun or the north star, but it is absolutely
important that you do something to calibrate those rotors.

You should find the middle beacon somewhere in the area of 145.270 to
145.320. Just tune around. Remember, the xtal in your downconverter is not
on the money and there is constituently changing Doppler which results in a
bit of a moving target. Once you have found it a few times, you will get the
hang of it and you can calculate just how far off your xtal is at any given
time. This will change due to outside temp. etc. and is not that important.
Remember that the beacon is OFF from MA 70 to Ma 87. NOVA will show you the
MA number, once you turn on that feature via "Views" "Current View","Format
Text". Select "MA", and "Squint Angle". In the "setup", "Satellites", select
AO40, and enter the Alat & Alon so that the program can compute the Squint
Angle ( The angle that the bird antennas have with respect to the center of
the earth.) Until the full inertia stabilization system is commissioned, we
rely on the spin stabilization method which gives us a forever changing
squint. As of today the Alat is -3 the Alon is 1.

Give it a try again. It is a blast!!
Let me know if I can help further.
Gunther Meisse

-----Original Message-----
From: Ed Polack [mailto:epolack@rmh2.org]
Sent: Wednesday, December 12, 2001 2:11 PM
To: gjmouse@neo.rr.com
Subject: Re: [amsat-bb] VI1GM available on AO-40

Hi Gunther, Ed N8eqj here. I'm trying to get started back into satellite
operation and have very little info or feel for AO-40. I tried for the first
time last night at about 8:00 EDST I,m located near Akron ,Oh . I co8uld not
find the Beacon. I was looking at about 2401.323mhz assuming my DEMconverter
144= 2400 to 148=2404. I,m using G3RUH patch feed and 60cm prime focus
dish. The receiver is an Icom910h I just received . Was the Satellite
about then Also I'm using NOVA tracking software and not totally confertable
with it yet. Backto you . Thanks in Advance, Ed

Gunther Meisse wrote:

> Gentlemen,
> If you are talking about this orbit #513. The telm MB has been up and
> working all day with the exception of MA 70-87 Rudak. I have copied 3086
> continuous blocks since MA 3.2 this morning.
> 73
> Gunther Meisse
> AMSAT LM:594
> -----Original Message-----
> From: owner-AMSAT-BB@AMSAT.Org [mailto:owner-AMSAT-BB@AMSAT.Org]On
> Behalf Of Lee
> Sent: Wednesday, December 12, 2001 2:29 AM
> To: Edwards, Paul; 'amsat-bb@amsat.org'
> Subject: Re: [amsat-bb] VI1GM available on AO-40
> Usually it means the dish got bumped or tipped over when I'm working
> portable.  I hope there was no unplanned shut down.  Right now the only
> the beacon is expected to be off is during the RUDAK period form MA 70-87.
> With the delays involved in email and the reflector it helps to include
> day with along with sticking to UTC time.  I'm guessing you mean 12/0100
> UTC.
> Lee-KU4OS
> ----- Original Message -----
> From: "Edwards, Paul" <PaulE@ise.canberra.edu.au>
> To: "'amsat-bb@amsat.org'" <amsat-bb@AMSAT.Org>
> Sent: Tuesday, December 11, 2001 20:41 PM
> Subject: [amsat-bb] VI1GM available on AO-40
> >
> > All
> > de Peter VK1KEP @ VI1GM http://www.vk1.wia.ampr.org
> >
> > I have subscribed from the University for today !
> >
> >
> > VI1GM is available on AO-40... but where is AO-40?
> >
> > Satellite telemetry does not seem to be there; it stopped abuptly at
> 0100UTC
> > when we were just getting our act really together.
> >
> > Can anyone please shed light on this?
> >
> >
> > Thanks,
> > Peter VK1KEP @ VI1GM
> >
> >
> >
> > Professor of Electronic Engineering and Applied Physics
> > Director, Centre for Advanced Telecommunications and Quantum Electronics
> > Research
> > University of Canberra  ACT  2601  Australia
> > +61 (0) 26 201 2515/2516/2411 (V)
> > +61 (0) 26 201 5041 (F)
> > paule@ise.canberra.edu.au
> > web: <http://beth.canberra.edu.au/atrc/>
> >
> >
> > ----
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> ----
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