Parks on the Air (POTA) is an operating program that encourages amateurs to set up portable stations in parks and other designated public areas and to contact one another. It has two roles: activators operate from the park, and hunters contact them from anywhere. It is popular because it is easy to start: a radio, a battery, a wire antenna and a picnic table.
How it works
Illustrative. Program rules decide what counts as a park, an activation and a valid contact.
The activator chooses a listed park, sets up, and calls CQ, often on HF phone, CW or a digital mode, sometimes also on VHF and UHF. The park's reference and the activator's frequency are posted as a spot on an online service, so hunters can find them. Hunters call in and the activator logs each contact. Afterwards logs are uploaded to the program, which tracks activations and contacts for each participant.
A contact between two activators, each in a park, is often called park to park, and is popular because it counts for both sides. A program defines how many contacts make a successful activation and what counts as a valid one; check its current rules before you go.
What you need
A transceiver. HF is the usual choice. A low-power (QRP) rig that runs on a small battery is common; see QRP and portable radios.
A portable antenna you can hang from a tree or a mast: a dipole, an end-fed wire or a vertical. See Portable and field antennas.
A way to log, on paper or in a phone or laptop app, and a way to post your spot.
Permission and local rules. Parks have their own rules about setting up, antennas, vehicles and noise. Check with the park before you go, and ask where you may put up an antenna.
Operating well
Pick a clear frequency and ask whether it is in use before you call.
Identify yourself and the park when you call: "CQ POTA, this is N0CALL" and the park reference where the program asks for it.
Be patient. If a crowd calls, work them in turn and keep each exchange short.
Hunters: listen to the activator's pattern, give your call once or twice and wait to be acknowledged. It is a pile-up in miniature; see DX etiquette and split operation.
Leave no trace. Keep wires out of walkways, away from people and pets and away from power lines. Pack out everything you brought.