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Disasters, such as hurricanes Helene and Melissa, are on the increase and many people need to communicate during a disaster but do not want to sit for the FCC amateur radio exam nor incur the expense of ham radios. Not to fear, there are three types of radios that could meet this need:

• Family Radio System (FRS) radios
• General Mobile Radio Service (GMRS) radios
• Mesh radios that send, receive, and forward text messages

You said:

Could you compare FRS radio GMRS radio and recent mesh radios based 915 MHz, the pros and cons for someone trying to build a local emergency communication system in the event we lose cell and internet as in hurricane Helene?

ChatGPT said:

Thought for 27s

Great question. Here’s a practical, side-by-side for disaster use (think: cell & internet down after a Helene-type storm). I’ll keep it plain-English and action-oriented.

What each is good at in an outage

FRS — “instant plug-and-play voice”

• Why use it: 
  • no license, already in many homes;
  • perfect for block captains to hail neighbors, hand out spares, or monitor a “neighborhood channel.” ARRL
• Limits: 
  • Range limited by fixed antennas and low power to not much beyond a neighborhood;
  • Number of radios could get very congested. Legal Information Institute
  • Everyone must agree on what channel and times to monitor. If you aren’t listening or transmitting on the right channel and at the right time, you don’t get the message.

GMRS — “community voice backbone”

• Why use it:
  • External antennas; mobiles/base units at much higher power dramatically improve range beyond a neighborhood;
  • license is easy and covers the family. Federal Communications Commission
• Limits:
  • Higher cost
  • Everyone must agree on what channel and times to monitor. If you aren’t listening or transmitting on the right channel and at the right time, you don’t get the message.

915 MHz LoRa mesh (Meshtastic) — “store-and-forward texts when voice can’t get through”

• Why use it: 
  • runs totally off-grid (no carrier, no internet),
  • each node forwards messages, so coverage grows as more neighbors power up;
  • uses minimal power;
  • can leave solar-powered “relay” nodes on rooftops/ridges;
  • supports channel-key encryption for privacy;
  • collects messages without human monitoring. Meshtastic
• Limits: 
  • text only;
  • very low data rate, seconds-to-minutes latency, and
  • encryption lacks features like PFS;
  • everyone must use the same firmware/app and share keys. Meshtastic

Feature	FRS (462/467 MHz)	GMRS (462/467 MHz)	915 MHz LoRa mesh (e.g., Meshtastic)
License	None	Required ($35 / 10 yrs, covers family)	None (Part 15 unlicensed)
Typical use	Family/neighbor handhelds (“bubble-pack”)	Community nets, mobiles, repeaters	Text-only off-grid messaging via mesh relays
Power limits	0.5 W on ch. 8–14; up to 2 W on 1–7 & 15–22	Up to 50 W (mobiles/base), repeaters allowed	Device-limited; up to ~+30 dBm ERP common in U.S. ISM band
Antennas	Must be non-removable	External antennas allowed	External antennas allowed (within Part 15)
Range (typical handheld)	~0.25–1 mi neighborhood	~1–3 mi handheld; 10–20+ mi via repeater/high site	0.5–3 mi urban; 5–20+ mi line-of-sight between high nodes; extends via hops
Throughput	Voice only	Voice + short data (text/GPS)	Low-rate text/position; store-and-forward mesh
Encryption	Not allowed (no coded/hidden messages)	Not allowed (no coded/hidden messages)	Yes (AES; PSK/DM keys), but with known limits
Interop with others	Many people already own FRS	GMRS can talk to FRS on shared channels	Requires same app/firmware & channel key
Complexity	Lowest	Low–medium (license, channel planning, possibly repeater)	Medium (flash radios, configure, manage keys)
Cost (ballpark)	$20–$80 per radio	$40–$120 HT; $150–$400 mobile; $35 license	$25–$120 per node + phone/app