Discriminator Tap Testing
So, you took the plunge, cracked open the scanner, and put a DiscriminatorTap on it. You hooked it up to your computer, and .... nothing. ...sigh...
Here's some basic steps you can use to try and figure out what's wrong.
Is there RadioCodeLine(?) in your area?
You did check this first, right? smile Turn on your scanner, and tune in the frequency you wish to monitor. Adjust the squelch on your radio so that it's just at the point where it goes silent (no static). Do you hear any bursts of data that sound similar to Fax or Modem sounds? If so, good, there's some kind of data in your area.
Analyze Signal window
Don't forget to adjust the volume of your sound card using the Analyze Signal window (the little green tool bar button with the sine-wave on it, or AnalyzeSignal(?) from the ViewMenu(?) ). This will chart the audio coming into the computer from your scanner so that you can properly adjust the volume. See the AnalyzeSignal(?) topic for more information on what looks good, and bad, as well as how to make the adjustments.
No Signal in Analyze Signal window: Check your connections
See the OtherWindows topic for examples of various examples of what the Analyze Signal window should and shouldn't look like.
If you're getting a flat line in the AnalyzeSignal(?) window, it's time to check your connections:
Are you plugged into the Line In (or Mic, if no line in) jack on the computer?
Are you plugged into the DiscriminatorTap port on your scanner?
Try hooking a pair of headphones up to your DiscriminatorTap, do you hear sound?
Yes: Then your DiscriminatorTap is (probably) okay.
No: Open the scanner back up and check your connections. Be sure nothing is shorting, touching, etc.
If you're getting audio out of your DiscriminatorTap with headphones, try hooking up something with a line-out to the laptop, such as a Walkman for instance. Ensure that the Walkman is playing, and see if you get anything in the AnalyzeSignal(?) window
Yes: Then your cables and sound card are probably okay. Look elsewhere.
No: Check your audio cable, and inputs.
-- BrianSwan - 26 Oct 2006