VE6DOK Search
Start Here

All Project Sites Results

Simplex Operation

Get Started

Simplex Operation

Talking radio-to-radio without a repeater: how it works, when it’s the better choice, and how far you can expect to get.

Written in Lethbridge, useful anywhere in Canada. The rules here follow ISED’s national amateur radio regulations, so they apply coast to coast. Local examples, like the VE6DOK repeater and exam arrangements, are for southern Alberta; your local club can point you to the equivalents near you.

Radio to radio, nothing in between

Simplex means both stations transmit and receive on the same frequency, directly to each other. No repeater, no internet, no infrastructure. If you can hear the other station, they can usually hear you.

It’s the oldest and most reliable way to talk on VHF and UHF, and it’s the one that still works when the power is out, the repeater is down or you’re somewhere a repeater can’t reach.

When simplex is the right choice

  • You’re close together: across town, in a convoy, at a campground or at an event. Tying up a repeater for a short-range chat isn’t good manners anyway.
  • The repeater is busy or down.
  • Emergencies and outages. A plan that depends on a repeater fails when the repeater does.
  • Testing your station. A simplex contact tells you what your own antenna and radio can really do.

How far will it go?

On VHF and UHF, range depends far more on antenna height and terrain than on power. As a rough guide:

  • Handheld to handheld, stock antennas: a few kilometres, less among buildings.
  • Mobile to mobile with roof antennas: often 15 to 30 km across open prairie.
  • Base station with an antenna up high: 50 km or more, and sometimes much further when the weather causes tropospheric ducting.

Coulees, hills and buildings block signals. Moving a few metres, or climbing a little higher, often makes the difference.

Frequencies to know

  • 146.520 MHz is the national 2 m FM simplex calling frequency. Make contact there, then move to another simplex frequency to chat.
  • 446.000 MHz is the common 70 cm FM simplex calling frequency.
  • Check the local band plan before picking a frequency, so you don’t land on a repeater input.

Good habits

  • Listen before you transmit, and give your callsign.
  • Agree on a simplex frequency in advance with family or your group, so everyone knows where to go when the phones are down.
  • Turn the repeater offset off. It’s the most common reason simplex “doesn’t work.”

Where to go next

Last updated October 2026.