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Docs Morse & Communication Two-Way Build

Two-Way Build

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Turning the beacon into a two-way radio: pairing with PMR446 or amateur handhelds, and the architecture that keeps it simple.

Two-Way Build

The beacon is one-way by design: it transmits, and you listen elsewhere. The two-way build pairs it with a handheld so the same kit can both signal and converse.

The pairing options

HandheldRoleNotes
PMR446Voice on 446 MHzLicense-free in Europe, integrated antenna
Amateur handheld (70 cm)Voice on the beacon’s bandNeeds a license
Second beaconMorse two-wayBoth sides beacon

The architecture

Keep the beacon as the automatic transmitter and the handheld as the voice channel. They do not need to share frequencies: the team listens to the beacon’s channel with one radio while talking on the handheld channel. This separation is deliberate: the beacon never stops beaconing, and the voice channel never gets clogged by the beacon’s bursts.

The audio bridge

The simplest bridge: plug the beacon’s audio jack into the handheld’s mic input, and the handheld re-transmits the beacon’s Morse on the voice channel. This is the trick that turns a PMR446 radio into a beacon receiver for a group (see Audio Jack Wiring for levels).

Why not a full duplex radio

A true two-way data radio needs collision handling, acknowledgments and a protocol. The beacon deliberately does none of this (see Firmware TX Scheduler); the Morse bursts are short enough that the loss rate stays low, and the repeats cover the losses.

The group build

For a group: each person carries a beacon plus a cheap PMR446 handheld. The beacons form the automatic distress net; the handhelds form the voice net. This is the configuration the Multi Beacon Planning page assumes.