[aprssig] APRS Voice Alert

[VE7GDH]

Dave (no callsign given) wrote on 07/09/2005

> I know from what has been said hear how it -*should*- be used, but in
> all honesty, with the limited band space we suffer, many people WILL
> chat on the APRS frequency as a result, through ignorance it has to be
> said.

I think you have a pretty good handle on how voice alert on APRS
works "over hear" and you have made an argument for why it won't work
"over theare", but I have a proposal that may make it workable for you -
especially seeing as how you have a D7. First, the beauty of  voice alert
as envisioned in the colonies:

If two mobile APRS stations have CTCSS enabled (100 Hz in North America) and
the squelch opens, you are probably within simplex range unless one of them
is running a lot more power than the other station. As described by Bob
WB4APR, one of the stations make a short voice transmission... something
like "WB4APR voice alert QSY 652" (sorry Bob if I jumbled the order a bit)
and then (either with or without a confirmation from the other station)
either announce themselves or make a call to the other station on 146.520 -
the national simplex calling frequency in North America.

If voice alert used this way is unworkable in your location - whether by
choice or technical reasons, why not propose this to your fellow hams?
Mobile APRS stations that have voice capability (whether they are using a
D7, D700, some other radio or even two radios, etc.) just enable a mutually
agreeable sub-audible tone on the mobile APRS radio. With tone squelch also
enabled on that radio, the user will hear the other station if it is within
range. Instead of making a quick "voice alert" call on the APRS frequency (I
take it that is what you are objecting to even though it seems to work OK in
this neck of the woods), merely go to your national simplex calling
frequency and announce your presence? Hopefully there aren't any technical
or other reasons for not making a call on the simplex frequency. <g> As long
as you can agree on the CTCSS tone to use and what your accepted simplex
calling frequency is, it should work.

73 es cul - Keith VE7GDH
--
"I may be lost, but I know exactly where I am!"