About Greenfield Police Frequencies
- 1 conventional channel is analog FM, so any scanner can receive it. Enter the frequency and set the tone shown in the table.
- Trunked radio systems that carry law-enforcement traffic here: STARCOM21 Statewide Illinois: 9 talkgroups. A trunking scanner is required, and it must support the system type shown.
- To follow a trunked system, program a control channel first. For Greenfield, start with the Dwight site of STARCOM21 Statewide Illinois, about 8 miles away. Its control channels: 852.05 MHz.
- 2 listed entries are marked encrypted. No scanner can decode encrypted audio.
Grundy County channels that also cover Greenfield
Tactical
| Agency | Description | Frequency (MHz) | Tone | Mode | FCC |
|---|---|---|---|---|---|
| Grundy County Sheriff Backup | Operations | 155.6850 In 158.9700 | 94.8 PL | FMN | KEW840 |
STARCOM21 Statewide Illinois
| Agency | Description | Talkgroup | Hex | Mode |
|---|---|---|---|---|
| Grundy County Sheriff | Operations | 2437 | 985 | D |
| Grundy County Sheriff | Operations | 2438 | 986 | D |
| Grundy County Sheriff | Operations | 2439 | 987 | D |
| Grundy County Sheriff | Explorers | 36000 | 8ca0 | D |
| Grundy County Sheriff | Car-to-Car | 2444 | 98c | D |
| Grundy County Sheriff | Grundy-to-Kendall Link | 2449 | 991 | D |
| Grundy County Sheriff | Jail | 2431 | 97f | D |
2 encrypted talkgroups (cannot be monitored)
| Agency | Description | Talkgroup | Hex | Mode |
|---|---|---|---|---|
| Grundy County Sheriff | Detectives | 3405 | d4d | D Encrypted |
| Grundy County Sheriff | Detectives – All | 3410 | d52 | D Encrypted |
Nearest trunked radio sites
Distances are measured from the center of Greenfield.
Dwight · STARCOM21 Statewide Illinois
RFSS 1 · Site 54 (hex 36) · NAC 142 · about 8 mi away
Control 852.05
Voice 851.15, 851.6125, 853.6125
Braidwood · Will County Government IL (P25)
Project 25 · RFSS 1 · Site 2 (hex 2) · about 9 mi away
Control 854.4875, 857.5375, 857.5875, 859.5875, 859.6375
Voice 854.6375
Saunemin · STARCOM21 Statewide Illinois
RFSS 2 · Site 67 (hex 43) · NAC 142 · about 20 mi away
Control 859.7125
Voice 854.1375, 855.2375, 856.2375, 856.9375, 857.9375
What do these numbers mean?
- Control channel
- The frequency your scanner listens to first. It tells the scanner where each voice call is happening, so program it before anything else.
- Voice
- The other frequencies the site uses for calls. A trunking scanner follows them automatically once it has the control channel.
- Site
- One tower location of the system. Scanners show the number in decimal or hex, so both are listed.
- RFSS (Radio Frequency Sub-System)
- A group of sites run by the same controller. Large Project 25 systems can have several.
- NAC (Network Access Code)
- A hex code the site transmits. Your scanner can use it to ignore other systems on the same frequency.
- Talkgroup
- A virtual channel on a trunked system, such as one agency’s dispatch. Programming uses the decimal or hex number, depending on your scanner.