Re: 14.070 Music


Jody - K3JZD
 

There are situations which would allow this to be done accidentally on a digital interface setup that relies on the VOX circuit to pickup the radio's PTT.  

For example, the microphone on my Icom IC-756pro3 is live all of the time - it does not connect and disconnect with the PTT Switch. So, if I had my always-live microphone connected, and I left the radio turned on with some digital mode software running, and I had a setup that relied on the VOX circuit to pickup the PTT, and then I got busy watching some YouTube video on the computer, then the microphone would pick that up audio and the VOX circuit would then key the transmitter. This always-live microphone situation may be typical for all Icom radios and maybe for some other brands. 

I do not use the VOX circuit to pickup my radio's PTT - my setup uses a COM Port. So what I just described is not a possibility for me.  However, I can still inject some unintentional audio while using a digital mode if I have left my always-live microphone plugged in. I watch my power output closely on my power meter.  If I see some fluttering in my power output whenever I am using some digital mode, that is a result of my live microphone picking up audio from the cooling fan in the radio or from my nearby 2 meter radio, or from any other nearby noise source.  So, although I will catch it quickly, and then unplug my microphone to eliminate it, I have been guilty of adding some garbage onto my digital signal for a short time once in a while.

Now, for me this is self induced pain because my Icom IC-756proIII has a USB-D Mode which is selected by pressing the USB button for 1 second after I am already in USB mode. If I remember to do that, then this USB-D Mode disables the microphone, eliminating the need for me to unplug it.  But, for one reason or another, I'm in the habit of [usually] unplugging my microphone so that I can move it out of the way.  So I hardly ever select that USB-D Mode.  Guess I should change my habit and start using that USB-D mode all of the time.

Jody - K3JZD

Join main@070Club.groups.io to automatically receive all group messages.