[amsat-bb] Re: New Satellite Downlink? Emergency ACKS

Robert Bruninga bruninga at usna.edu
Fri Aug 27 05:55:44 PDT 2010

OK, I think I have an application idea that would apply to
emergency comunications response.

Since this is a mostly one-way downlink satellite channel (that
can be received with ANY FM receiver a vertical whip and a
laptop with sound card), this means it can be fielded in the
emergency area very trivially.  The use of this channel would be
to ACKnowledge the receipt of outgoing health and welfare
traffic.  I would propose that the MARS volunteers could manage
this during an emergency.

Currently traffic from an emergency is usually one-way outbound,
and all inboud health-and-welfare concern traffic is blocked to
keep the channels open.  But if this satellite broadcast channel
was available, then outboud traffic could assign a code number
to each outbond message and when that was delivered to the final
recepient, then the code number coiuld be sent back over the
satellite broadcast channel to confirm delivery.  In addition, a
few digits could also be appended to indicate typical responses
from a pre-set response list.

So, for normal non-emergency times, the channel would be for
Q-tweets to exercise the system.  During emergencys, the
downlink could be switched over to this emergency ack system.


> -----Original Message-----
> OOPS!  Wait!  I have a very sharp DCI BANDPASS
> filter up there!  Duh....  Ill try a different 
> antenna this time!

Yep, heard it fine on an HT with a long whip.

>>> Possible new AMSAT Application?
>>> We may have access to two old TRANSIT navigation 
>>> satellites with a 50 baud downlink at 149.985 
>>> (and 400 MHz).... My problem is, coming up with
>>> any meaningful application to use them for 
>>> communications that would capture the interest 
>>> of students, hams or volunteers in support 
>>> of education, public service or emergency comms 
>>> or just plain fun...
>>> The total useful message capability is about 500 
>>> bytes transmitted every 2 minutes (at 50 baud). 
>>> The uplink is very specialized and can ONLY BE 
>>> DONE from one (or two) very special commmand 
>>> stations.  

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