# Mast and Pole Mounting

## Safety first

**Erecting and climbing masts is hazardous.** Before any mast work:

- **Overhead power lines:** Keep the mast's full fall radius clear of power lines - allow a clearance of at least the mast length plus 10 ft in every direction. A falling or tipping mast that contacts an overhead line can be fatal; power-line contact is the leading cause of installer electrocution.
- **Never raise a mast alone.** Use a spotter, and never raise or work on a mast in wind or near power lines without help.
- **Fall protection:** Use fall protection for any rooftop or elevated work, and do not climb push-up or telescoping masts - they are not rated to support a person.

## Mast options

- **J-pipe mounts:** Common TV antenna hardware. Good for moderate antennas on walls or chimneys.
- **Galvanized conduit:** 1-1.5" Schedule 40 steel conduit. Strong, affordable, easy to work with. Suitable for short unguyed masts (commonly cited around 4-5 meters), but the safe free-standing height depends heavily on wind load and antenna weight - for taller masts or heavier antennas, guy the mast or consult a structural/EIA-222 or manufacturer guideline rather than relying on a flat height figure.
- **Telescoping push-up masts:** Aluminum sections. Easy to deploy. Common for temporary or semi-permanent installs.
- **Non-penetrating roof base:** A weighted base holds a mast on a flat roof without drilling. Ballast requirements scale with mast height and antenna wind load - 50 lb of paving blocks is a minimum for short masts only. Calculate the overturning moment for your wind zone; tall masts may need several hundred pounds of ballast or guying. An inadequately ballasted mast can blow over, becoming a falling hazard or striking power lines.

## Guy wires

Masts more than about 3-4 meters free-standing (and any telescoping push-up mast above roughly 4 m) need guy wires. Use three guys at 120 degree intervals (a triangular arrangement). Use stainless cable or UV-resistant rope. Guy at 2/3 height and near the top. The exact threshold depends on mast type, antenna wind load, and exposure - guy sooner for heavier antennas or windy sites.

## [Grounding and lightning protection](https://wiki.meshamerica.com/books/antennas-rf/page/grounding-and-lightning-protection)

Ground the mast and antenna with a bonding/down conductor not smaller than #10 AWG copper (NEC 810.21); #8 AWG or larger exceeds this minimum and is fine. If you drive a separate ground rod for the antenna, it **must** be bonded to the building's main grounding electrode system with at least a #6 AWG copper conductor (NEC 810/250) - grounding the mast to its own isolated rod without bonding to building ground creates a dangerous ground-potential difference and is a code violation. Install a coaxial lightning arrestor rated for 915 MHz at the building entry point and bond it to building ground. See the dedicated [grounding and lightning protection](https://wiki.meshamerica.com/books/antennas-rf/page/grounding-and-lightning-protection) page for full detail.

## Key rules

- Mount antenna as high as practical, clear of obstructions
- Keep the coax run short by mounting the radio enclosure close to the antenna
- Use stainless steel hardware outdoors to prevent galvanic corrosion
- **Never power on the radio without an antenna connected** - transmitting into an open or shorted port can damage the power amplifier. LoRa transceivers (SX126x/SX127x) often survive brief keying into an open port, but sustained transmission without a proper load can cause permanent damage, so always connect the antenna (or a 50-ohm dummy load) before transmitting. This caution applies most during bench testing - see the getting-started and testing material.