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Re: AO51 Digipeater Trial Test



>>> "Michael Kingery" <<On 19 Dec >>>
> The Digipeater...  on AO-51 has been turned on 
>for a "Trial Test Session".... this is a shared resource.  
>We are using one uplink, so the PBBS users and digi 
>users are going to be on the same uplink frequency.
>... It will take a higher gain receiving station to hear 
>the [low power] 9k6 signal of AO-51. 

Mike, 
I notice the digital is off, presumably to save power so
that the Voice repeater can operate at high power
over the holidays.  I wonder if the digipeat mode can
operate in PTT mode independently of the BBS?

The reason I ask is because digi mode is a very very
low dutycycle mode compared to the BBS.  WHile
operating the BBS consumes a lot of downlink RF power,
operating in digi mode would not even be noticible to
the power budget even if the digital tranmitter was
operated at max power.  Our estimates for PCsat was
a whole world average dutycycle of less than 2% even
while supporting up to 70 users per day.

If ECHO could be operated in digi mode independent
of the continuous BBS downlink, then it could be operated
at the full TX power for those fractional second packets
and be receivable with a handheld most of the time, while 
using hardly any significant average power.  

But of course, this assumes that theAO-51  digipeat mode
can operate in a PTT-per-packet mode.  Maybe the
current software load does not allow this?

ANyway, the very low dutycycle of UI-digipeating
while using the TX in high power should be considered
as the optimum way to enable digital handheld
communications..

Just a thougt...
Bob, WB4APR
----
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