Module 2 - VHF Radio Basics
Set-Up Controls Before The First Call
What you will learn
Set up the actual radio in a repeatable order and verify the displayed channel, watch facility, power and receiver controls before transmitting.
A safe set-up is an observed sequence, not a remembered default. Power the set, read the display, establish audible reception, confirm the channel and watch mode, select suitable transmit power and preserve a readable display.
Start with the vessel's operating instructions. Confirm the radio has the correct supply, power it on, read the displayed channel and look for warning or position-status indications. Raise volume to a usable level, then set manual or automatic squelch according to the radio's instructions.
Select the intended channel and verify any dual-watch or scan facility. Do not assume the channel that stopped a scan is the one you intended to use. Confirm low/high output before the call and know the control that returns directly to Channel 16.
Use the display dimmer to protect night vision without making the channel, power, position or alert information unreadable. Press PTT only when ready to transmit and release it immediately afterward. The final check is behavioural: can you hear, identify and respond while still navigating safely?
Use a repeatable first-call set-up
You join a night watch and the previous operator has left the display dim, scan active and the power setting unclear.
1. Read before changing
Identify the current channel, scan or watch state, power level and any warning indication.
2. Make reception usable
Set a readable dimmer level, audible volume and device-appropriate squelch.
3. Confirm the call state
Select the required channel and power, listen, transmit only when ready, release PTT and restore the watch.
Sense check: A display that is comfortable in darkness is still too dim if the channel or alert state cannot be read without delay.
Common mistake or limitation
- Changing controls before noting the inherited radio state.
- Copying one manual-squelch routine to an automatic-squelch radio without checking its instructions.
- Dimming the display until safety-critical information is unreadable.
Recap
- Use the radio's manual and confirm the actual displayed state.
- Make reception audible before transmitting.
- Verify channel, watch mode and transmit power.
- Keep the display readable and release PTT to receive.
Optional quick check
Section 8 of 9
What is the best final check after setting the channel, volume, squelch, dimmer and power?
Sources and factual review
Reviewed 20 August 2026 - Compass Revision editorial review.
Continue studying VHF Radio Basics
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