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Re: Need help with FO20 and FO29



Hi Dave

I had a think about your problem, and here's some thoughts...

Yes, you can work the FO birds on 3W. But it's not recommended for
_reliable_ contacts. Like using an HT and rubber duck on the FM birds, you
have to be both lucky (for different reasons - a nice high elevation pass
for instance) and a seasoned operator.

The use of CW to get your downlink prior to operating SSB is the same method
that I use. It gives you the opportunity to set your frequencies, optimise
your antenna position(s) and polarisations.

There's a couple of remarks you made which almost nullify each other as to
what advice to give: RS-13's ok (ie your 2m uplink's good); but on the FO's
your signal is well below that of other stations (your 2m uplink's bad).

Mmmm...

If you can work RS-13 OK, your uplink should be OK for the FO's. So I think
maybe you might want to try improving your downlink first, preferably with a
directional antenna. Although elevation and polarization switching are
helpful, as they add further to the reliability of your link, they're not
essential. You don't need that many elements. I use 7x7 for my downlink and
it really works quite well, although I can switch polarization.

I have regularly worked the FO birds with just a vertical, but although it's
not too tough to do, it wasn't very reliable. However, having the option of
a bit more uplink power helped when my signal was significantly weaker than
other stations. Hearing my own downlink with CW was quite easy, but I
regularly disappeared on SSB in fading either due to polarization mismatch
or because the bird was out of my antenna's radiation pattern. I often had
times when I lost QSO's, and was have heard stations accusing me on a couple
of occasions that I was unable to hear the downlink... when really I just
couldn't get in. I don't think they realised that I could hear them
perfectly on the downlink!

A couple of questions... Is your 2m Yagi horizontal, under elevation as well
as azimuth control, or is it at a fixed elevation, such as 20 degrees or so?
Putting some elevation on may help a bit, especially on overhead passes. On
an 'overhead' pass (not that there's many of those), the eggbeaters should
be fine. Or have you put the eggbeaters at elevation on a rotator K5OE
style?

73 Howard G6LVB

----- Original Message -----
From: Dave Barrows <dbarrows@my-deja.com>
To: <amsat-bb@AMSAT.Org>
Sent: Friday, September 22, 2000 3:51 AM
Subject: [amsat-bb] Need help with FO20 and FO29


> I still have not been able to make any ssb qsos with the FO20 and FO29
sats.
>
> My equipment:
>
> FT-726 - 10 watts max out
> eggbeater II on 70cm with SSB electronics preamp
> eggbeater II and 11 el cushcraft linear on 2m
> (the cushcraft is vertical and aimed at the horizion so I use the
eggbeater for higher elevations)
> approximately 40 feet of LMR400 on all antennas
>
> alternatively:
> arrow antenna hand held
>
> I have made cw contacts on FO20 and FO29 with limited success. When I do,
I still have trouble losing myself in the downlink. This is partially
because my signal seems to be weaker than other stations I am hearing and
partially because when I adjust my transmitter frequency to match where I am
hearing the other station, I forget to switch to the receive vfo and when
the other station starts transmitting, I am trying to
> tune it in with the transmit vfo until I have moved the transmit frequency
out of range before discovering my mistake.
>
> Now, on ssb, I can't find myself at all until I do it first on cw. To
transmit on cw, both 70cm and 2m vfos must be on cw.  After I find myself on
cw, I can sometimes switch the 2m vfo to lsb and the 70cm vfo to usb, say
"aaaaahhhhhh" and zero in my signal.  But I lose my signal in the downlink
shortly thereafter and have to switch the receive vfo back to cw, then
switch to the transmit vfo and put it back on cw, then find my signal again.
Once I have found it again, I must put the transmit vfo back on lsb again
and
> switch back to the receive vfo and put it back on usb again, then switch
back to the transmit vfo and fine tune myself back on frequency again.  (The
rig will allow for transmit on one
> sideband on one vfo and receive on the other sideband).
>
> When using the arrow antenna, it is even harder because I have one hand
tied up moving the antenna's el, az, and polarization as well
> as all the switching, keying with the same hand I use to turn the vfo knob
on cw, and using the up/down switch on the mike to move the frequency on
ssb.  Did I mention that I was turning the antenna's el, al, and
polarization to maximize my signal in the downlink?
>
> Now, I have been told that using 3 watts and an arrow antenna I should be
able to work ssb with on an overhead pass of the FO birds.  What am I doing
wrong?  I am trying to run my satellite station on a shoestring budget.
Will I have to
> wait until I have more power and better antennas to work ssb?
>
> I have made several ssb contacts successfully on RS-13 mode A.  But I seem
to have a lot better signal into RS-13, the doppler is not as bad, and since
I use a totally different rig for receive I know which vfo I am adjusting
and I can switch the transmitter from cw to ssb without having to switch the
receiver.
>
> Dave W8IJ
> Camp Hill, PA FN10
>
>
>
>
>
> --== Sent via Deja.com http://www.deja.com/ ==--
> Before you buy.
> ----
> Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
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>

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