[amsat-bb] Re: SO-50 under-utilized over North America

Martin Gillen va3sie at gmail.com
Wed Nov 8 22:11:39 PST 2006

Hi, John & Everyone,

Thanks for all the support and information - Wow!!

Well I just had a go!

I had a 70 degree pass, SO-50 was travelling up the East Coast.

I made a mistake though :)

I was out on the balcony with my FT-51R clipped to my jacket, earbuds
connected to a speaker/microphone, the 70cm side tuned to 436.805, the
2m side tuned to 145.85 74Hz tone. (The FT-51 tunes in a 5kHz step

I didn't hear anything at the beginning of the pass so I send about 4
seconds of 74kHz tone and then switched to 67Hz.  (I have two adjacent
channels on the same frequency with different CTCSS).  I then sent my
callsign a couple of times but I didn't hear anything.

Thats when I remembered to take the squelch off (Doh!).  Now I heard a
callsign W2ZZ something like that... my hands were full and I was
excited so I forgot :}... anyway I sent my call again and this time I
heard a kind of squeal on the downlink.  I waited a second and tried
again, and again I heard a squeal.

Then I remembered there is a dip switch in the back of the speaker
microphone that mutes the speaker!  The downlink audio was being
feedback straight back into the speaker microphone - Oops!!! So:
Sorry about the interference I created on the sat tonight!

Once I fixed that the sat was already on its way back down toward the
horizon.  I sent my call again and then Wow!! I heard myself (vy.
weak) but I also heard someone else come back to me, I heard "SIE" ...
Great!!  Unfortunately I could not tell who called me, the sat was
very weak now... maybe 15 degrees elevation.

It's really hard to coordinate the doppler correction on the RX side
with pointing in the right direction with paying attention to whats
going on, on the air, as well as rotating the elements during speech
to optimise the signal.  I need more arms!

Anyway:  It's a start.  I think I'll just listen for the Saturday
morning pass and then play on AO-51 a bit next week.

Thanks all who replied - I'll send some personal responses a bit later.

Did I say.... Wow!


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