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Re: Mode L uplink Question



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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