RF Path • Height • Loss

Antennas, Feedline, and Coverage

Coverage is not just transmitter power. It depends on antenna height, feedline loss, connectors, duplexer/filter losses, receiver performance, terrain, foliage, buildings, and local noise.

Core concepts

What members should understand

This guide explains the core concepts, practical operating habits, and documentation discipline members need to use the system responsibly.

Antenna

Radiation pattern

The antenna determines where RF energy goes and what signals the receiver can hear.

Feedline

Loss and damage

Long coax, poor connectors, water intrusion, and corrosion can waste power and reduce receive sensitivity.

Terrain

Real coverage

Hills, valleys, buildings, and trees often matter more than theoretical range maps.

System diagram

RF path from radio to coverage

A simplified signal or workflow path members can use to understand the system before asking deeper technical questions.

1

Transmitter

RF leaves the repeater transmitter or user radio.

2

Feedline and filters

Coax, jumpers, duplexers, filters, and connectors introduce loss.

3

Antenna

Height and pattern shape the useful signal.

4

User location

Terrain, antenna, receiver, and noise determine what is actually heard.

How it works

Learning notes

VHF/UHF repeater coverage is often line-of-sight influenced. Raising antenna height and keeping the RF path clean can improve practical performance more than simply increasing power.

ARRL learning material explains that repeaters help overcome the limits of handhelds, vehicles, valleys, and local terrain.

A useful coverage report includes location, radio type, antenna, whether the operator was indoors or outdoors, signal/audio quality, and time of day.

CBRA application

Connector discipline: Weatherproofing and clean connectors prevent slow failures.

Known-location testing: Repeat tests from the same locations over time to detect degradation.

Noise awareness: Local electrical noise can make a receiver seem worse even when the transmitter is fine.

Practical checklist

What to check before changing anything

These are safe learning and documentation steps, not permission to modify repeater, tower, electrical, or club infrastructure without approval.

Inspect

Look first

Check visible coax damage, loose connectors, water entry, corrosion, and strain relief.

Measure

Use tools

SWR, continuity, and loss checks should be done with appropriate equipment and safe procedures.

Compare

Use baselines

Compare current reports against known good reports from the same area.

Reference shelf

Authoritative learning sources

Learn more through trusted amateur-radio references and official service resources.

FCC Part 97

Amateur Radio Service rules, station responsibilities, and operating standards.

Open source ->

ARRL Repeaters

Plain-language repeater basics and practical operating guidance.

Open source ->

AllStarLink

Official overview and support for amateur-radio VoIP linked systems.

Open source ->

EchoLink

Official software and license-validation information for EchoLink users.

Open source ->

Next step

Think in complete paths

A radio signal depends on transmitter, receiver, antenna height, feedline loss, connectors, grounding, terrain, and operator location. Improving one part may not fix the whole path.

Scroll to Top