FAQ

Q: What is FRS?

A: FRS stands for Family Radio Service and is a low-power 22 channel two-way radio service in the UHF 462/467 MHz range. Shares same frequencies with GMRS.


Q: What is GMRS?

A: GMRS stands for General Mobile Radio Service, and is a medium-power 22 + 8 (repeater) channel two-way radio service in the UHF 462/467 MHz range. Shares same frequencies with FRS.


Q: Is CAVERN Channel 8 or 9, 15, 23 or what?

A: All of the above! CAVERN is heard on 462.550 MHz which is GMRS/FRS Channel 15, however different radios access this channel via different channel locations. CAVERN-programmed RETEVIS RT22 hear.

Q: How do I monitor for emergencies only?

Q: How do I alert people to an emergency?

Q: What constitutes a local emergency?

Q: Does CAVERN own these channels?

Q: Why can’t people hear me?

CAVERN Channels

CAVERN’s preprogrammed Retevis RT 22 radios channels match the way most FRS/GMRS radios are programmed, but only for the first few channels. This is because the RT22 only has 16 channels and cannot transmit at the legally required 0.5 Watts for FRS channels 8-14 (so we left those out for now).

What this means in practical terms is that on CAVERN pre–programmed FRS radios (e.g. the “Retevis RT22”), Channels 1-7 correspond to most off-the-shelf FRS radios, HOWEVER: CAVERN’s Channels 8-16 are NOT programmed to the standard frequencies and tones.

This table below shows: pre-programmed CAVERN channel locations (in the first column); the corresponding normal “Standard” FRS and GMRS channel location for most non-CAVERN radios (i.e. the “factory settings”) and; additional CAVERN frequency & tone settings for radios (i.e. to help limit Main Repeater access to Cobb Area volunteers):

CAVERN ChStandard ChFreq/Tone (Info)
1Ch 1(Group 1 Boggs)
2Ch 2(Group 2 Cobb)
3Ch 3(Group 3 BottleRock)
4Ch 4(Group 4 Hobergs)
5Ch 5(Group 5 Seigler)
6Ch 6(Group 6 Hannah)
7Ch 7TBD (not used by CAVERN)
8Ch 15462.550 Megahertz
+ DCS: D071N
(CAVERN Repeater
/ Daily Talk
& Weekly Check-Ins)
9Ch 15462.550 Megahertz
+ CTCSS: 103.5 hertz (aka “tone #13”)
(CAVERN Emergency Alerts/Tests ONLY)
10-16Ch 16-22TBD (not used by CAVERN)

CAVERN Emergency Channel

Not everyone wants to listen to a scanner or CAVERN throughout the day…and especially at night. Luckily CAVERN programmed radios can screen out the day–to-day chitchat on the frequency, so that you only hear alerts of local emergencies put out by fellow CAVERN volunteers.

Monitoring

To screen out chitchat set your CAVERN-programmed RETEVIS RT22 to channel 9, or (newer) BTECH GMRS V1 to channel 33. Additionally any FRS/GMRS radio that supports privacy tones can be set to the standard channel 15 with a “privacy tone” or CTCSS receive tone of 103.5 Hz. (Often tone #13 corresponds to 103.5 Hz.) Consult your radio’s manual or send email to Net Control.

NOTE: We test the Emergency Alert channel tone at the beginning of our check-ins or when a Fire siren is tested. But we conduct the actual check-in roll calls on our non-emergency channels! (RT22 Ch 8, GMRS V1 Ch 15 or 23, most FRS/GMRS radio ch.15 with NO privacy tone.) If you modify your radio to hear the Emergency tome, be sure to reset your radio to the regular channel after test or you may not hear anything else!

Transmitting

Should you need to announce an emergency, first listen and ask on the non-emergency channel if the network is already aware of the emergency.

If there is imminent danger to the some part of the Cobb area (as in a moving fire within 1-3 miles likely to require evacuation) put out an emergency alert with as much detail RETEVIS RT22 to Ch 9, or BTECH GMRS V1 to Ch 15 or 23 with CTCSS 103.5 set on transmit. Additionally any FRS/GMRS radio that supports privacy tones can be set to channel 15 with a “privacy” or CTCSS tone corresponding to 103.5 Hz (often named tone #13).