[amsat-bb] AO-40 heard on 2.4GHz in VK

[Chris Hill <CRH_Telnet@xxxxxxxxxxx>]

Hi all,

I saw a bit of discussion as to whether AO-40 can be heard or not on
2.4GHz, and thought I'd drop a quick note to tell you I've just heard it.

Setup here:

Antenna is a small mesh parabloid, intended for the 2.4GHz ISM band,
nominal gain of 20dBi, linear polarisation, lying on the back lawn, with a
stick propping it up at the correct elevation angle!

Downconverter is a modified Drake 2880, nominal downconversion of 2256.27
MHz.  This downconverter was connected straight into the N-connector of the
20dBi "dish", and the 2m IF then fed via 3m of RG-58 to an FT-736.

I assumed a transmit frequency of 2401.326 MHz from AO-40, then adjusted
for doppler...  and found AO-40's 400bps beacon at a dial frequency of
145.026 !!

First heard signal at approx 2000-Dec-29 01:50 UTC (earliest I could lash
the gear together, due to other committments), and lost signal at approx
2000-Dec-29 03:20 UTC, as squint angle increased beyond estimated 60 degrees.

Even with this bodgy setup, the beacon was strong...  I'm now working to
clean it up, and get a 400bps demodulator working.

Good to hear the bird again!  If I can do it with this setup, so can
anyone...  along as the squint angle is low enough.

(I used Alat / Alon = -2.2,+81 in Instant Track for my squint angle
guestimates).


Happy Listening,


Chris vk6kch
(QTH is 32.050S, 115.850E)






----
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org