Radio Channels

Understanding the Frequencies

The channels in this list operate across several different radio frequency bands, each serving specific purposes:

• GMRS (462-467 MHz): General Mobile Radio Service channels. These require an FCC license and are how ERSN communicates. For channels with a mode of Tone or TSQL listed, you will need to request access to the tone from the repeater owner. Please email ersnnets@gmail.com for access to the ERSN repeaters.
• Amateur Radio (144-148 MHz and 420-450 MHz): Also known as "ham radio" bands. Channels CARS (145.170) and SUMMIT (441.875) fall in these ranges and require an amateur radio license to transmit.
• Public Safety (151-155 MHz): Used by fire, police, and emergency services. These frequencies are for monitoring only - transmitting on these frequencies is restricted to authorized agencies. Note that the VHF band they operate in is shared with other services like MURS and Business Band frequencies, which operate on different specific frequencies within this range.
• Federal (167-172 MHz): Used by federal agencies including forest service and park service. These frequencies are also for monitoring only.

About Offsets and Tones:

• Duplex Offset: When you see "+ 5.0" or similar, this means the radio transmits 5 MHz higher than the receive frequency. This is common for repeater systems.
• Tone: When "Tone" is listed, it means the channel requires a specific tone to access a repeater. Think of it like a password that helps prevent interference between different groups using the same frequency.

Remember: While anyone can listen to these frequencies, transmitting requires appropriate licensing and authorization depending on the service. Always ensure you have proper licensing before transmitting.

Understanding Tone vs TSQL

Tone Mode (CTCSS Encode)

• When a channel is set to "Tone", your radio only adds a tone when transmitting
• Your radio will receive all transmissions on that frequency, whether they have a tone or not
• This is most commonly used for accessing repeaters, which require a specific tone to activate
• Think of it like adding a "key" when you transmit, but leaving your "door" open to all incoming signals

TSQL Mode (CTCSS Encode/Decode)

• TSQL stands for "Tone Squelch" and works in both directions
• Your radio adds the tone when transmitting (like regular Tone mode)
• Your radio only lets you hear transmissions that include the matching tone
• This filters out other users who might be using the same frequency with different tones
• Think of it like having a matching key and lock - you need the right tone to both transmit and receive