CHA RXL
Page 3
Introduction
Thank you for purchasing and using the Chameleon Antenna
TM
Low Frequency (LF) / Medium Frequency (MF) / High
Frequency (HF) Receive Loop Antenna (CHA RXL). You are now part of the magnetic loop antenna craze that is
sweeping the amateur radio and shortwave listener community. Magnetic loop antennas have been used for
decades by armed forces around the world, but are just now receiving serious attention by hams and SWLs. The
CHA RXL is a new design high performance LF / MF / HF receive-only loop antenna that is weather resistant and can
be permanently mounted on an outdoor TV-style antenna mast, used portable on an apartment balcony or next to
an RV using a camera tripod, or indoors placed on a table top. The CHA RXL can receive on all frequencies from
135.7 KHz to 30.0 MHz with no tuning.
Its’ broadband design
and high-performance preamplifier make the CHA RXL
ideal for Software Defined Radios (SDRs), panadapters, hams wanting a small low-noise receive antenna, shortwave
listeners (SWLs), AM broadcast band listeners, or anybody needing a small receive antenna.
Receive loops are very quiet and highly directional. With the built-in preamplifier, the CHA RXL will enable clearer
reception than many large horizontal wire or vertical antennas. Field trials demonstrated that with the CHA RXL
mounted outside, signals were typically only around one to two S-units lower than a full-size dipole antenna, but
that interference was less, resulting in improved readability.
The CHA RXL consists of a rigid 36-inch Loop, a Loop
Preamplifier, a BIAS-T DC Power Injector, a 12V DC
Power Supply, and mounting bracket. Plate 1 shows
the CHA RXL mounted on a camera tripod on a deck.
The key design features of the CHA RXL are:
✓
Portable - small, lightweight, and easy to setup;
✓
Reduced noise;
✓
Highly directional;
✓
Wideband design
–
covers LF/MF/HF;
✓
Electronic preamplifier with negative gain slope -
more gain at the low end, where it’s needed
most;
✓
Balanced input electronic preamplifier to
eliminate environmental noise and ground loops;
✓
Power protected from reverse polarity and short
circuits;
✓
Flexible mounting options
–
TV mast outside,
camera tripod, or table top;
✓
Stealthy
–
the powder-coated Navy gray loop
fades into the background sky;
✓
Flexible power
–
use included 120V AC power
supply or operate portable using 12V DC; and
✓
Receives on new 2200m and 630m ham bands -
become a WSPR Reporting Station and join the
fun!
Plate 1. CHA RXL on Camera Tripod
(tripod not included).
A small receiving loop antenna receives at all
elevations from horizon to zenith, making it an
equally effective antenna for both receiving local
(including
NVIS)
and
long-distance
(DX)
communication. It is highly directional in the plane of
