The Hotel Antenna is a clever space-saving vertical antenna design popular among VHF and UHF amateur radio operators. It is especially useful for radio amateurs living in apartments, hostels, or temporary locations where installing large outdoor antennas is not practical. Despite its compact and folded physical shape, electrically it behaves like a classic half-wave vertical dipole with excellent impedance matching and a clean radiation pattern.This VHF Hotel Antenna, also commonly described as an end-fed vertical dipole with an offset (Z-shaped) feed section.
Originally shared by HS3FYV, this antenna has proven to be simple to build, visually unobtrusive, and highly effective for FM operation on both the 2 meter and 70 centimeter bands.
Why it’s called a Hotel Antenna
The name comes from its compact, folded shape, which:
- Fits easily on balconies, hotel rooms, apartments
- Looks less like a traditional antenna
- Can be mounted close to walls or railings with minimal visual impact
Electrical Concept and Working Principle
Although the antenna looks unusual, its operation is straightforward. The two long vertical sections form the radiating elements of a dipole. The short horizontal sections simply shift the feed point sideways, keeping the coaxial cable away from the active radiating area. This improves pattern symmetry and reduces common-mode current on the feedline.
Because the antenna is balanced and close to 50 ohms, it can be fed directly with standard coax without the need for gamma matches, coils, or tuning stubs.
2 Meter Band Hotel Antenna Dimensions (144–146 MHz)
The following dimensions are optimized for the 2 m amateur band and are suitable for 145 MHz FM operation.
- Vertical radiating sections: 131 cm each
- Horizontal offset arms: 28.8 cm each
- Distance between vertical elements (horizontal span): 30 cm
- Conductor material: 10 mm aluminium or copper pipe
- Feedline: 50 ohm coaxial cable
With these dimensions, the antenna typically shows an SWR close to 1.1:1 and provides performance comparable to a standard vertical dipole.
70 Centimeter Band Hotel Antenna Dimensions (430–440 MHz)
For the 70 cm band, the antenna can be scaled down proportionally. The following measurements are a practical starting point for 435 MHz.
- Vertical radiating sections: 43.5 cm each
- Horizontal offset arms: 9.6 cm each
- Distance between vertical elements (horizontal span): 10 cm
- Conductor material: 6–8 mm aluminium or copper pipe
- Feedline: 50 ohm coaxial cable
Minor trimming of a few millimeters may be required to achieve the lowest SWR, depending on construction accuracy and mounting environment.
Hotel Antenna – Radiation Pattern and Performance
The Hotel Antenna produces a vertically polarized, omnidirectional radiation pattern, making it ideal for FM repeaters and local simplex contacts. Gain is similar to a half-wave vertical dipole, typically around 2–3 dBi, with a low radiation angle that favors ground-wave and repeater work.
When mounted clear of metal objects and at a reasonable height, it performs noticeably better than handheld antennas and many compromise indoor antennas.
Installation and Practical Tips
This antenna works best when mounted vertically on a non-conductive mast or balcony railing. Keeping the coax routed straight down from the feed point helps maintain pattern symmetry. While a choke balun is not mandatory, adding a few turns of coax near the feed point can further reduce common-mode currents.
Its discreet shape makes it suitable for stealth installations, a key reason why it has earned the name “Hotel Antenna.”
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