Module 2 - VHF Radio Basics
A Simple Pre-Call Check
Before pressing PTT, identify whom you are calling, verify the published channel and listen. Confirm usable volume and squelch, the intended transmit power and the vessel identity. Put the request, position or other critical information in a short order that can be spoken clearly.
After transmitting, release PTT and listen. If there is no reply, do not fill the channel with a continuous or increasingly long call. Recheck the channel and radio state, wait for a reasonable interval, repeat briefly, or use the appropriate alternative procedure for the priority and risk.
A no-reply result is evidence, not a diagnosis. The other station may be busy or not listening; the channel may be wrong; your receiver, antenna or power may be mis-set; terrain may block the path. If the situation becomes urgent or distressing, change to the correct priority procedure rather than repeatedly treating it as routine.
| No-reply check | Question | Unsafe shortcut |
|---|---|---|
| Channel and watch | Is this the current channel, and is either station listening? | Calling continuously |
| Receive controls | Can weak traffic pass the volume and squelch settings? | Adding transmit power |
| Antenna and range | Is the path screened or the installation damaged? | Assuming a fixed mileage |
| Priority | Is this still routine, or have conditions genuinely changed? | Inventing urgency |
Optional quick check
Section 7 of 9
Which is the strongest routine pre-call outline?
Sources and factual review
Reviewed 20 August 2026 - Compass Revision editorial review.
Continue studying VHF Radio Basics
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