Order Tray | Contact Us | Home | SIG Lists

[aprssig] Operator Present Bit

Stephen H. Smith wa8lmf2 at aol.com
Fri Sep 26 05:23:11 UTC 2008

Mark Cheavens wrote:
> Write an add-on that looks at the screen saver mode. (And/Or monitor 
> power saver).
> Have it change the overlay and send a beacon whenever the state of 
> the screen saver or power mode changes.
>> Yes, for years we wanted to use the CASE of the N/S byte to
>> indicate operator present.  But unitl someone re-wrote Uiview,
>> we would never see their operator status.  So recently, we added
>> the O OVERLAY idea.  But then again, if it is not automatic when
>> the person enters the room and touches the PC and then decays
>> off when the person leaves the operator position, then it is a
>> worthless capablity.

The problem with this is that I (and a lot of other users) have more 
than one computer in the operating area.  I always have the APRS PC 
running.   I may be within 3 feet of the APRS/Echolink/SSTV pc for hours 
on end (so that I would hear or see a message coming in) but I am 
interacting with (keyboarding or mousing) a completely different computer. 

Any operator status bit based on keyboard activity on the APRS PC would 
normally never get set.

Just had an idea for a solution.   

Program a TinyTrak with the identical settings in the primary and 
secondary modes, except for the overlay symbol.  Set the beacon rate to 
once every 30 mins or so.   Connect the primary/secondary mode select 
switch to an IR motion sensor in the shack, and configure the sensor 
with a fairly long hang time -- perhaps 10 minutes when it is 
tripped.     Wire the TX audio and PTT of the TT in parallel with your 
main TNC or soundcard interface to the APRS radio (or use the mini-DIN 
input on a D700 or 710).

As long as you are absent, the TT will beacon once every thirty minutes. 
Entering the room will trip the motion sensor to flip the TT to 
secondary mode. When it is switched, it re-initializes, immediately 
sends a beacon with the "Operator Present" overlay set and then starts 
the once-every-thirty-mins routine starting from that time. It will then 
continue to beacon "Operator Present" once every 30 mins as long as you 
hang around.  Leaving the room will reverse the process when the motion 
sensor times out and switches the TT back to the primary mode -- an 
immediate beacon without the "Operator Present" overlay, and then once 
every 30 mins.  


Stephen H. Smith    wa8lmf (at) aol.com
EchoLink Node:      14400    [Think bottom of the 2M band]
Home Page:          http://wa8lmf.com  --OR--   http://wa8lmf.net

World Digipeater Map

JavAPRS Filter Port 14580 Guide

"APRS 101"  Explanation of APRS Path Selection & Digipeating

Updated "Rev H" APRS            http://wa8lmf.net/aprs
Symbols Set for UI-View,
UIpoint and APRSplus:

More information about the aprssig mailing list