What is Project GMRS?

Project GMRS connects radio operators through 76 pages for profiles, club forums, messages, repeater tools, contact logs, and secure member access.

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Power & ERP Calculator

Estimate system loss, EIRP, and ERP from transmitter power, antenna gain, and feedline losses.

Transmitter Power (W)

Antenna Gain (dBi)

Coax Loss (dB)

Connector / System Loss (dB)

Total System Loss

2.00 dB

EIRP

126 W

ERP

76.6 W

EIRP uses antenna gain in dBi; ERP ≈ EIRP / 1.64 (gain expressed as dBd). Estimates only — actual figures depend on antenna pattern, VSWR, and installation.

FCC compliance: GMRS limits vary by channel type — e.g. 50 W ERP on repeater channels (15–22) and 0.5 W on channels 8–14. These estimates do not confirm legal compliance. Always verify your effective power against current FCC GMRS rules before transmitting.