In addition to Neil's comment - you would screw up the APRS operation if you do not listen and prevent your own APRS broadcast from going out during another APRS transmission. You could key up on top of the ongoing transmission and both your own and the other packets would be QRMed.
73 - Jim W5ZIT -----Original Message----- From: [EMAIL PROTECTED] To: [email protected] Sent: Thu, 14 Dec 2006 10:34 AM Subject: [Repeater-Builder] Newbie Information Time - Mystery Signal In my opinion, is a slight flaw in the voice operation on 144.39 MHz below ... the FCC requires you to monitor the frequency in a non-CTCSS mode prior to transmitting. And, if you have your 144.39 MHz receiver locked up on CTCSS decode, your receiver won't hear the packet operations ... Thank you for your time, Neil McKie - WA6KLA ----- Original Message ----- From: Max Slover <[EMAIL PROTECTED]> Date: Wednesday, December 13, 2006 4:58 pm Subject: Re: [Repeater-Builder] Mystery Signal > In case I confused anybody, this is what I am refering > to with APRS and a 100hz tone --- > > VOICE ALERT: This simply means that you do not turn > the audio down on > 144.39, but instead leave it at high volume and then > simply set CTCSS > tone 100 to mute the speaker. This way, you dont hear > any packets, but > ANYONE can call you with VOICE on 144.39 to alert you > by using PL 100. > You will rarely use this, and only use it to tell > someone to QSY to another > voice channel, but it is one way of assuring that > ANYONE running APRS in > simplex range of you can ALWAYS be contacted with a > voice call... > > You wont hear any packets except maybe one or two > when another VOICE- > ALERT mobile is in range (about 3 miles or so). But > even then, he is only > beaconing once every 2 minutes and so it is not > bothersome at all.. > In fact, it is nice to hear when someone is nearby! > Its like a free radar > for other mobile APRS operators that are in simplex > range AND listening. > > --- > > --- Max Slover <[EMAIL PROTECTED]> wrote: > > > Doh, this just hit me. It would most definitely be > > an > > APRS setup due to the 100hz subtone. In APRS you set > > the subtone to 100 so you can do voice alert. Man, > > why > > didn't I think of that part when this was first > > mentioned. > > > > Sorry for being a bit late on that but I figured I'd > > toss my 2 cents on this. > > > > Max... > > > Public Information Officer -- St. Louis & Suburban Radio Club > K0AZV - Amateur > WPWH-650 GMRS > St. Louis County ARES > St. Ann MO EM48tr > > > > > > Yahoo! Groups Links > > > > ________________________________________________________________________ Check Out the new free AIM(R) Mail -- 2 GB of storage and industry-leading spam and email virus protection.
