About Johnson County Police Frequencies
- 9 conventional channels are analog FM, so any scanner can receive them. Enter the frequency and set the tone shown in the table.
- 1 conventional channel uses a digital mode (TELM), which needs a scanner that decodes that mode.
Johnson County conventional frequencies
Dispatch
| Agency | Description | Frequency (MHz) | Tone | Mode | FCC |
|---|---|---|---|---|---|
| Johnson County Sheriff | Law Secondary / (Former Fire Dispatch) | 154.2950 In 153.8900 | 136.5 PL | FMN | WPKN385 |
| Johnson County Sheriff | Local | 155.5350 | FMN | KNDU272 |
Tactical
| Agency | Description | Frequency (MHz) | Tone | Mode | FCC |
|---|---|---|---|---|---|
| Johnson County Sheriff | Johnson County Sheriff – Tactical Channel | 155.5800 | FMN | WPGS700 |
Jails & Corrections
| Agency | Description | Frequency (MHz) | Tone | Mode | FCC |
|---|---|---|---|---|---|
| Shawnee Correctional Center [K-19] | Operations | 453.7750 In 458.7750 | 127.3 PL | FMN | KNDW211 |
| Shawnee Correctional Center [K-19] | Operations/Armory (Vienna) | 453.8750 In 458.8750 | FMN | KNDW211 | |
| Vienna Correctional Center (Johnson) [K-X] | Water Distribution Data | 453.2063 | TELM | WPYW733 | |
| Vienna Correctional Center (Johnson) [K-X] | Daily Operations, Armory / Hardin Co Work Center | 453.3250 In 458.3250 | 127.3 PL | FMN | KNDW210 |
| Vienna Correctional Center (Johnson) [K-X] | Armory/Operations | 453.3500 In 458.3500 | FMN | KUA774 | |
| Vienna Correctional Center (Johnson) [K-X] | Daily Operations, Armory | 453.7750 In 458.7750 | 127.3 PL | FMN | KNDW211 |
| Vienna Correctional Center (Johnson) [K-X] | Administration / Hardin County Work Center | 453.8750 In 458.8750 | 127.3 PL | FMN | KUA774 |
Radio system sites in Johnson County
Program the control channel first; your scanner finds the voice channels from it.
Cypress · STARCOM21 Statewide Illinois
RFSS 3 · Site 17 (hex 11) · NAC 147
Control 851.9875, 852.825, 853.925
Voice 851.4625
Vienna · STARCOM21 Statewide Illinois
RFSS 3 · Site 21 (hex 15) · NAC 146
Control 772.54375, 773.79375
Voice 769.46875
Goreville Omnipoint · STARCOM21 Statewide Illinois
RFSS 3 · Site 34 (hex 22) · NAC 142
Control 769.19375, 773.54375, 774.21875
Voice 770.68675
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.
Cities & communities in Johnson County
Common questions
What frequency do the police use in Johnson County?
Dispatch channels listed for Johnson County: Johnson County Sheriff 154.2950 MHz (136.5 PL); Johnson County Sheriff 155.5350 MHz.