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Re: AO-40 AGC study,please read it!



Fred W0FMS wrote:

>I suspect 1m dish owners are hearing "well enough" with reasonably low
>squints but the BBQ dishes have always been marginal.  During higher
>squints, the 1m dishes are marginal and so on...  I started with a 4' prime
>focus dish and a patch feed and then tried a BBQ... The BBQ was not even
>close.   The 4' was good except for the worst conditions.  But a 10' would
>have probably salvaged the worst conditions....

>I think we need to let everyone know that BBQ's are really only okay as a
>receving setup when the sat is at very low squints....and that
>no, really, bigger is better.

Hang on!  Some of us can't have "bigger is better".  I went from a 24 dBi
BBQ to a 60cm offset dish and the local authorities sent me a letter in
regard to "illegal antennas"!
So I had to go back to the BBQ.  Also the portable guys can't carry around a
2.4m 'BUD'.

I have also pulled down my 70cm antenna to check if it is OK, removed the
antenna mounted 70cm pre-amp thinking that I have a problem on 70cm, because
I don't get in as well as I did when AO-40 UL/S2 was first switched on, and
this was without the dish antenna and 2.4 GHz pre-amp.  Now I don't use SSB
at all it's not worth the argo having to continually bump up the power to
make an impact, which increases the problem.  And there are far more CW ops
on the bird who have also found that they can't make the trip on SSB.  10
watts has been just fine for CW and PSK for me.  My mode L setup is very
marginal 10 watts into a 25 ele loop yagi and this is fine with squints
below 15 on CW.

Maybe we have a combination of the U Rx being pounded and the U Rx not (dare
I say it!!) being as good as it was at transponder switch on.  I have
observed at 2:00 AM local time when the sat is practically empty, the
footprint is over Asia, Africa and VK.  And the only sigs are some JAs
having a chat 80 KHz above and some very low FM 30 KHz below the beacon and
that the U Rx is not as good as I remember it was.

I agree that there are many people that are running far too much power and
SSTV is a very major AGC thumped.  I have a PCR-1000 I use as a slow spec-an
on the bandpass and I have seen SSTV signals that are stronger then the
beacon.  When these SSTV stations are just talking to each other their
signals are nominal so the upshot on running SSTV is to turn the output of
your soundcard down, most modern radios don't use the mic gain control on
the acc/data input on the radio.  LEILA doesn't seem to notice SSTV so this
will continue until we reach the sad point of "outing" these operators.  But
on the same token I have also seen SSB ops with signals stronger then the
beacon that LELIA takes no notice of, and CW ops having signals stronger
then beacon (which is just plain stupid).  And it doesn't help that some
moron has a recording of LEILA and runs up and down the transponder playing
it over those HE feels are running to much power.

I feel it is now time to break the operations up like they where on AO-13.
Modes U/S, L/S, UL/S, L/SK, U/SK, V/S this should show the individual merits
of the different modes and kill off (for a time) the infighting that is
starting to take place. What say you?

Matt -VK2DAG-

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