What type of modulation are they using?

Status
Not open for further replies.

gmclam

Member
Premium Subscriber
Joined
Sep 15, 2006
Messages
5,380
Location
Fair Oaks, CA
I've had the FBI frequencies programmed for a while now. What I thought I was hearing was a repeater passing through noise from a receive frequency with no carrier. Then the other day I heard one person in the clear talking to someone who was not. And when the person not in the clear transmitted, I'd hear that same sound; it sounds like RF noise.

Today I picked up the same thing on a Secret Service frequency. So I suspect it is some form of modulation that our scanners are not designed to handle. Can someone tell me what it is?
 

gmclam

Member
Premium Subscriber
Joined
Sep 15, 2006
Messages
5,380
Location
Fair Oaks, CA
Yes, the audio sounded the same except for a "beep" near the end of your wav file. I don't hear the beeps, just the noise.

What is the type of modulation used for these transmissions? QAM, PSK, or ???
 
Status
Not open for further replies.
Top