[amsat-bb] Little Girl that lives aboard AO-85

Jerry Buxton n0jy at amsat.org
Thu Jun 30 17:55:42 UTC 2016


On 6/30/2016 09:43, Paul Stoetzer wrote:
> The voice beacon "Hi, this is amateur radio satellite
> Fox-1" is transmitted when the transponder has not been keyed up for
> three minutes.
FWIW, that's two minutes after the hang timer (downlink) stops and every
two minutes thereafter until the hang timer is activated again by
receiving an uplink signal.  If the hang timer is activated during the
ID, the ID will stop.  Also in Safe Mode, the ID is every two minutes.
For those of you keeping score, it's actually about every 2 minutes 11
seconds from the start of the previous ID because the two minute timer
starts after the completion of the ~11 second ID.
Each ID whether Transponder Mode or Safe Mode contains one current
telemetry frame and one high or low telemetry frame, with the high/low
alternating each ID (Current/High, Current/Low, etc.)  There are no
experiment frames in the voice ID telemetry.  There is no voice ID in
Data Mode.
The first (current) telemetry frame is sent prior to the ID audio to
help ensure that it can be decoded if there are problems.  The voice ID
commences at the second (high or low) telemetry frame.
Each ID allows a second or so for the "Fox Tail" to come up to the
downlink frequency and then pauses about 1/2 second prior to beginning
the telemetry/announcement so that a "dead carrier" is transmitted for
Doppler sensing as part of an experiment that Douglas Quagliana KA2UPW/5
is working on in a future ground application.

Veronica will be present on all four of the Fox-1 FM satellite series.

Maybe we should have a contest or award, capture/transcribe all eight
Transponder Mode/Safe Mode voice IDs (they are all different, each of
the four Fox-1 FM satellites) for bonus recognition as a hard core
satellite nerd!     :-)

Jerry Buxton, NØJY



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