[amsat-bb] 73 on 73 Award Reminder

Paul Stoetzer n8hm at arrl.net
Sun Aug 31 19:41:47 UTC 2014

Just a reminder that the award period for the 73 on 73 Award begins at
0000Z on September 1st, so begin keeping track of the unique callsigns that
you work on AO-73. When you reach 73 unique callsigns in your log, email me
at n8hm at arrl.net with a list of calls, date, and time worked (in UTC) and
your mailing address. I hope to have a website up soon with an example of
what the award will look like.

Some tips for working AO-73:

-Keep in mind the frequency drift on the transponder. The offset needed on
your transmit frequency is usually from +10 kHz to +16 kHz. This can vary
throughout the pass, requiring frequency adjustments if using computer
control. Many find manually tuning the uplink to maintain a constant
downlink to work better than computer control.

-I usually start a pass by trying to find myself come into the top
edge of the passband (145.970 MHz). To do this, I usually start
transmitting around 435.135 MHz and tuning up slowly until I can hear
myself enter the passband. Then I can move around the transponder
easily. Remember to tune your uplink to maintain an constant downlink
frequency (the opposite of FO-29).

-Keep power output down. The transponder has a very sensitive receiver
and a very active AGC circuit. Excessive uplink power will not make
your signal louder - it will only reduce that available for others on
the transponder. With a clear view of the horizon, 5 watts to an Arrow
or Elk is plenty for horizon to horizon coverage. Very slightly more
might be necessary if you are beaming through trees or other
obstructions, but try to keep power to 25-40 watts ERP.

Good luck! Who will claim the 73 on 73 Award #1?


Paul Stoetzer, N8HM
Washington, DC, USA (FM18lv)

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