[amsat-bb] Re: AO-7 Milliwatt Report

Bruce Robertson ve9qrp at gmail.com
Wed Jun 3 08:46:30 PDT 2009

On Wed, Jun 3, 2009 at 10:57 AM,  <n3tl at bellsouth.net> wrote:
> Hey everyone,
> My thanks to K8YSE, who heard my faint CQ on AO-7 at 13:16 UTC this morning and called me. We had a contact that lasted about a minute with a few exchanges, which is really a thrill here because I was transmitting a half-watt out on a Yaesu FT-817ND.
> As I suspected from the "test run" the other night, my setup here requires that AO-7 reach roughly 50 degrees elevation before I can hear myself at all on this lowest-of-all power settings for my SSB/CW satellite station. I also suspect I can lower that elevation some by working CW instead of SSB, and I intend to find out on the next really high pass over me.

This is an interesting experiment. It is worth pointing out to those
who might not be familiar with this bird that 50 degrees as a minimum
elevation on AO-7 is much more practical than for lower elevation
birds, such  as AO-51. I suspect the time that AO-7 is above 50
degrees on some passes is about the same amount of time that VO-52 is
above the horizon! Moreover, because of the greater footprint, when
you transmit to AO-7 overhead, you might still reach a different
continent or other excitingly distant stations.

Another consideration regarding Tim's experimental approach is that it
is ideal for situations in which a low-gain antenna is being used for
reception. It is better for everyone if in these circumstances we do
not increase our transmission power until we can hear ourselves
(especially on AO-7, which FMs quite a bit). Keeping the xmit power
low and waiting until it can be heard is a good way to experiment
without causing problems.

73, Bruce

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