Waltham Police & Fire

FYI THE FEED DELAY IS ON THE ORDER OF ABOUT 2 MINUTES AND TIMING BETWEEN CALLS MAY NOT BE PRESERVED; HOWEVER, NOTHING WILL  BE LOST IF, FOR EXAMPLE, BOTH THE PD AND FD ARE ACTIVE AT THE SAME TIME.

THREE Frequencies Monitored:

(1)
Location: Waltham, MA
Frequency/Modulation: 470.5125 MHz (Conventional P25 Phase 1)
Alpha Tag: "Waltham PD-1"
Description: "Police F1 Operations"

(2)
Location: Waltham, MA
Frequency/Modulation: 470.1125 MHz (Conventional NFM)
Alpha Tag: "Waltham FD1"
Description: "Fire Ch 1 Operations" (analog only)

(3)
Location: Waltham, MA
Frequency/Modulation: 472.225 MHz (Conventional NFM)
Alpha Tag: "Waltham FD2"
Description: "Fire Ch.2 Fireground"
12/20/25 - I have become concerned about AI-driven services scraping my audio and reporting things like simulated active-shooter training as actual mass-casualty events. Once, several years ago, I found myself "fooled" for more than a few minutes. For this reason, I may remove coverage of "Waltham FD2" in the future.

HARDWARE:
Raspberry Pi 4 with TWO "Nooelec NESDR SMArTee XTR SDR" connected to a Tram scanner antenna stuck to a grounded piece of sheet metal.
Yep.

SOFTWARE:
Largely followed this guide.
trunk-recorder recompiled to use the older p25 decoder