[aprssig] Re: aprs wish list

Bob Burns K4RXR k4rxr_ at rlburns.net
Tue Aug 15 12:58:34 CDT 2006

Quoting Steve Bragg <steve at hamhud.net>:

>> 6. Whatever radio that I use for APRS will be dedicated to APRS and
>> not have to do dual duty as a voice radio. I would like to implement
>> Voice Alert using CTCSS 100 Hz as described in the APRS documentation.
> You mean Bob recommends transmitting voice on 144.39?  I'll have to 
> go  back and read that one...

No, I don't think that's exactly what he's recommending.

Quoting from MOBILE.TXT packaged with APRS876.ZIP:


VOICE ALERT!  The concept called Voice Alert is like getting a FREE APRS voice
calling channel in your mobile for ALWAYS being able to contact an APRS mobile
no matter what freq his voice radio is on. Its also like a radar detector for
other mobile APRS operators in simplex range on the open road.  It is 

Instead of turning the speaker volume down on your noisey 144.39 
channel, simply
set CTCSS decode to 100 Hz.  This accomplishes 2 things:

1) It keeps your speaker quiet but everyone who understands voice alert knows
they can contact you by voice by simply calling on PL 100.

2) It causes your outgoing packets to have PL 100 to serve as a radar ping to
other Voice Alert stations in range.  Conversly you will never hear 
anything on
your 144.39 voice alert unless anotehr APRS voice alert station is in simplex
range (about 5 miles max)

These two make sure you will have an opportunity for a voice call to QSY to 52
or other channel for a QSO.  On the interstates you pass another ham
statistically about once every 10 minutes.  But you never know it.  With Voice
Alert, you now will be aware of each other's presence AND you will have 
contact frequency.


For what it's worth, I've been running Voice Alert around Central and Southern
Indiana for the last month. I've heard one station transmitting a 100.0 Hz PL


More information about the aprssig mailing list