The classic G5RV Antenna , invented by Louis Varney (G5RV) in 1946, is a staple of amateur radio. It’s known for its ability to operate across multiple High-Frequency (HF) bands with the aid of an antenna tuner. But at a length of about 102 feet (31.1m) for the full-size version, it’s often a tight squeeze.
The design pictured is a clever adaptation, sometimes referred to as a “half-size” or “junior” variant, tailored for smaller properties while still providing excellent multi-band coverage.
G5RV Antenna – Key Features of This Design
- Compact Radiator: The dipole element is shortened to just 3.75 meters (approx. 12.3 ft) per side, for a total length of 7.5 meters (about 24.6 ft). This is a major space saver compared to the full 102-foot design, making it perfect for attic installs, small yards, or portable operations.
- The Matching Section: At the heart of the G5RV’s multi-band magic is the vertical feed-stub. Here, it’s 1.22 meters (approx. 4 ft) of 240 to 450 Ohm twinlead or ladder line. This section is not a transmission line in the typical sense; it acts as an impedance transformer, helping to present a manageable impedance to the coax on multiple bands.
- Balun and Feeder: A 4:1 Transformer (often a voltage balun) is used at the junction of the twinlead and the 50 Ohm Coax. This transformer helps convert the balanced signal from the twinlead to the unbalanced coax, and further aids in matching the impedance to the standard 50 Ohm input of your transceiver or a tuner. The coax can be “Any Length,” offering flexibility for routing the feed line back to the shack.
- Targeted Bands: This particular shortened version is optimized for a wide range of frequencies: 14-50 MHz (20m through 6m bands). This is ideal for operators focused on DX (long-distance) and VHF frequencies.
Installation and Mounting
The shortened G5RV antenna can be installed in several configurations:
- Horizontal dipole: Best for high-angle radiation and local coverage.
- Inverted-V: Easier to mount with a single support; provides broader matching and less directional pattern.
- Portable or field use: Compact size allows quick deployment between trees or masts.
Typical mounting height is 6 to 10 meters (20–33 feet) above ground. Higher installations improve overall radiation efficiency and lower takeoff angles for long-distance communication.
The Shortened G5RV antenna is an excellent compromise for the amateur radio operator who needs multi-band functionality in a small footprint. If you’re chasing DX on 20 meters and up, or need a compact setup for Field Day or portable operations, this design offers a fantastic balance of size and capability.
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