[aprssig] RE: Opentracker Event Counter

scott at opentrac.org scott at opentrac.org
Thu Dec 30 11:23:52 EST 2004

That's a good idea.  Hadn't thought about the duty cycle timer.  That
probably wouldn't be possible on the IRQ input I'm using, since it's edge
triggered.  I'll have to think about how to do that, but it might have to
wait for a future version with more I/O pins.

The tracker does have fairly accurate timing (+/- 20 ppm), but it doesn't
count anything while it's transmitting.  Usually that's not a big deal.

Thanks for the input, that's just the sort of thing I was looking for.


-----Original Message-----
From: Komljanec Family [mailto:komljanec at sympatico.ca]
Sent: Wednesday, December 29, 2004 11:13 AM
To: aprssig at lists.tapr.org
Cc: scott at opentrac.org
Subject: Opentracker Event Counter


The event counter (hits since last reset) will be most useful for tracking
repeater activity.  It can be tied to the transmitter PTT (this is straight
forward) or even the RX COR, although this may be prone to high counts due
to COR chatter when subjected to weak signals. Unless some sort of timed
debounce is used (one event every second?).

Similarly, if you have stable time keeping, a small twist to this would be
to count the time that the event counter input is in its active state.  In
the above example, it could track the total time the TX is up, the generator
is running, like an hour meter.

The issue with most APRS telemetry devices is that they provide snapshot
telemetry values that are observed at the instant the packet is sent.  Your
event counter proposal takes things to a new level, since it will track
activity BETWEEN telemetry packet bursts.  Same idea for a weather station
application. maximum rate of rainfall, logging maximum wind gust, etc,

Great work Scott!


Tony K

> Scott Miller wrote:
>> I'm working on adding a new feature to the OpenTracker that'll let you
>> count
>> events on one of its input pins.  It'll probably have a couple of modes -
>> number of counts since reset, number of counts since last transmit, and
>> maybe counts per hour.  I'm looking for ideas on possible inputs.  Some
>> suggestions:

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