I think there are still one or two spiratic birds operating on ten metres
FM.
there used to be one all the time, but I think there was some issues with
the onboard power supply or something.
Anyway, up and down angle isn't as important as being able to turn the
antenna to follow the path.
If you want to be able to work satelites at all times of the day and
maximize the pass window, then perhaps having the ability to tilt the
antenna would allow that. But I don't think it is worth it for the extra
cost and trouble of a tilting roter.
Everyday there are passes that are well within the angle for a flat antenna
to work.
You asked about power before as well, and you can work satelites with very
very little power, but I would say no more then 5 watts should be necesary
on FM.
In fact, I think AO51 has a QRP input frequency and a regular input
frequency, but they ask that you utilize as little power as possible to
minimize the satellite's receivers power consumption.
73
Colin, V A6BKX
----- Original Message -----
From: "Richard Fiorello" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, May 29, 2008 2:07 PM
Subject: Re: satolite operation
> Hi;
> That is a good start. At one time ten meters was used for I believe the
> output frequency but that may be long gone. As for the rotator the
standard
> rotator will just change the horizontal direction that the beam is
pointing.
> How is the antenna adjusted vertically or isn't that necessary?
> Richard
>
> ----- Original Message -----
> From: "Colin McDonald" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Thursday, May 29, 2008 1:36 PM
> Subject: Re: satolite operation
>
>
> well, most people who work satelites are using, at the minimum, a multi
> element beam for both the UHF and VHF sides.
> The way the amateur satelites work, is that the receivers on the satelite
> will receive on one band, say UHF, and the transmitter will transmit on
> another, say VHF.
> You can buy dual band beams anywhere from 3 elements and up. These are
> usually sold as satelite antennas. Cushcraft sells several different
models
> relatively inexpensively.
> Typically, the satelites transmitters, and the band you have to receive on
> your radio is in the 432 to 438MHZ range, either on FM or SSB or CW or one
> of the digital modes.
> The satelite receives, and where you have to set your transmitter is
> usually in the 145 to 146MHZ range. Some satelites flip these around.
> There are several good FM satelites, so you don't have to worry about
> getting a VHF/UHF SSB capable rig if you don't have one...though it might
be
> a great reason to buy the ts2000 if you don't already have it.
> The beam must be rotatable so that you can follow the satelites path
across
> your sky.
> there are several programs that will help you determine when the satelite
> will be in range for you, and how long it will last, and the angle it will
> be crossing at. You can get this info from the amsat.org website:
> HTTP://www.amsat.org
> and click on path predictions and enter either your grid square or lat and
> long position.
> You can work satelites with a hand held, or vertical antenna, but your
> maximum usable time is extremely limited due to the horizon and sheer
> distance.
> Also, vertical antennas tend to have a sharp angle of radiation and you
need
> a pretty low angle to work most satelites.
> A directional beam antenna usually has a low, 25/28 degree radiation
angle.
> anyway, hope that answers your questions?
> another note is that most of the satlite tracking programs also have the
> capability to control certain roters and position your antenna acording to
> the path of the satelite within range.
> 73
> Colin, V A6BKX
> ----- Original Message -----
> From: "Richard Fiorello" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Thursday, May 29, 2008 12:28 PM
> Subject: satolite operation
>
>
> > Hi everyone;
> > Has anyone on the list done any satellite work? I'm wondering how much
> > radio and antenna are needed? I believe at one time you needed a
receive
> > preamp at the antenna but I'm hoping that has changed. What frequencies
> are
> > most common and how much power is needed? Also what kind of antenna
> systems
> > have worked well? I have heard mention of a "egg beater" antenna but
> never
> > found out what the thing looked like.
> > Richard
> >
> >
> > --
> > No virus found in this incoming message.
> > Checked by AVG.
> > Version: 7.5.524 / Virus Database: 269.24.3/1472 - Release Date:
5/29/2008
> 7:27 AM
> >
> >
>
>
> --
> No virus found in this incoming message.
> Checked by AVG.
> Version: 7.5.524 / Virus Database: 269.24.3/1472 - Release Date: 5/29/2008
7:27 AM
>
>
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