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Re: Mode L uplink Question



Mike, Jerry, and all:

I had a busy day yesterday in the sunny 50ish Alaska spring wx and got my
U, L, and S antennas mounted on the roof.  Tonight I will run coax and
install the Drake to see how the 18 inch RCA DSS offset dish hears.  I will
use my FT-817 for IF up on the roof [fortunately its flat] since I am
manually moving the antennas [rotor forthcoming]. My AOS is ~0630 UTC [2230
local].  If I hear it well enough I may transmit on U to see If I can hear
my signal.

I have a 2.4G preamp on the way so may need that in front of the Drake.
Hoping the test period runs long enough.  I will call DEM today to get an
est. on shipping of my 144/1268 Tx Conv.  

Equipment run down:
FT-847 {in the shack}
432:  50w amp in roof-mounted box, M2-436CP42 {16.5 dBic} ...up to 2kW ERP
{LEILA tester}
1268:  DEM 144/1268-1270 {15-18w} roof-mounted, 45 EL loop-yagi {20
dBi-vertical} ...900w ERP est.
2400:  45cm dish RHCP, Kuhne MKU-232A {0.7 dBNF/35 dB gain}, Drake#1 {123
MHz}, Drake#2 {433.9 MHz}
10451:  45cm dish, DEM 10451/144 Rx Conv {??? now with X-band test failure}

Ed
BP40iq


>From: K5OE@aol.com
>N1JEZ wrote: 
>
>> My feeling is that when AO-40 is finally oriented 
>> towards us with minimal squint, my 600 w erp linear 
>> uplink will be more than adequate. Don't forget 
>> that the S downlink will also be stronger as well 
>> when squint is low. I don't plan to change a thing at 
>> this time.
>
>Mike,
>I concur, especially the part about not changing a thing.  I know lots of
people are frustrated at being unable to hear the bird or to hear it well.
This weekend's pass over N.A. was very educational for a lot of us.  I
noted I could copy the beacon better at 62,000 km (S5 with S1 noise level)
with good squint than I could at 30,000 km (S2 with S0 noise level) with
poor squint.  I still have not figured out the pattern to the background
noise at 2.4 GHz.  The clue to me I needed just a little more receive gain
was when trying to find my downlink by pinging the bird, I kept setting off
LEILA (about 250 W ERP): I guess that's why they call me an amateur :-)
>
>My receive setup is really quite marginal, being built to test out my
S-band receive and not necessarily for long-term AO-40 use.  Having the
setup a year in advance and playing around with UO-11's downlink and the
few months of S-band telemetry helped a lot getting prepared for the
short-notice "experiment."  My 16-turn helix is small and far from optimum
in design (it was just easy to build and used convenient materials I had on
hand).  It served it's primary purpose--to prove out my receive setup.  I
am designing and building a new, larger helix, but am not too concerned yet
as the final orbit and orientation of the satellite will probably make more
difference than any modest antenna improvements I might make to my station.
 I suspect (and hope) patience will be rewarded in regards to AO-40.
>73,
>Jerry, K5OE
>
>
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