Hello Operators. Today on OH8STN Ham Radio we are discussing a Portable Ham Radio HF antenna that covers 6 HF bands, yet requires no antenna tuner. The antenna design is called an End Fed Half Wave antenna. This design is fed from one end of the radiating element, having an electrical length of one-half wavelength at the design frequency. This one is from Chameleon Antenna. It is called the LEFS (Lightweight End Fed Sloper). This video focuses on testing and performance. Spoiler alert: The LEFS does exactly what it says on the tin!
A more familiar example of a half-wave antenna is the centre-fed dipole. We use the end-fed antenna design for a few different reasons. Firstly, despite the assumptions, it is a multiband (harmonics) antenna. This one is designed for and resonant on 40 meters. It also provides excellent performance on 20m, 17m, 15m, 12, and 10 meters respectively.
Other reasons for choosing this type of antenna are the various configurations we can deploy it in. Although the name says “Sloper” antenna, this is just one of the various antenna configurations we can use. The Chameleon LEFS can also be configured as:
- Inverted L
- Inverted Vee
- Sloping Vee
- Horizontally for NVIS
All of these antenna configurations while still being fed from one end, and without all the radial wires required for a full-size vertical antenna.
Generally speaking, the half-wave antenna fed from the end is one of the best performing yet most forgiving antenna designs available to the field radio operator today. Here are a few bullet points:
- Incredible performance.
- Extremely light weight
- Fed fron the end
- Multiple bands
- No mess of ground radials.
Want more information?
Radio used for testing was the Icom IC-705.
The amplifier mentioned in the video was the PA500 from diy599.com. Watch my video series here or find technical details and documentation here. There is quite a substantial waiting list for this passionately designed and built amplifier.
Lots of effort goes into these posts. Researching and testing each component, software application, pragmatic field testing. When you see these posts, the mistakes and blunders have already been filtered out. If you find any value in that, share this post and/or buy me a rootbeer.