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100MHz ground plane antenna - Here
you can find plans for a simple ground
plane antenna that works well in the FM
Band (88-108MHz). It's built of a small
plastic disk…
6 x 6 Loop Antenna - This new loop
antenna by Graham Maynard is his best
design yet and I am proud to be the
first to present his work. It uses one,
six foot square, six turn loop, and is
aperiodic in nature, covering the
frequency range 50KHz - 5000KHz...
Active Antenna - An antenna with an
integrated RF pre - amplifier
Active Antenna AA-7 HF/VHF/UHF,
3-3000MHz - If you have a shortwave
or high-frequency receiver or scanner
that is struggling to capture signals
with a short, whip antenna, and you'd
like the kind of performance that a
60-foot 'longwire' antenna can provide
but lack the space to put one up,
consider building the AA-7 HF/VHF/UHF
Active Antenna described in this
article.…
Active Antenna for AM-FM-SW - This
simple little circuit can be used for
AM, FM, and Shortwave(SW). On the
shortwave band this active antenna is
comparable to a 20 to 30 foot wire
antenna. It is further more designed to
be used on receivers that use untuned
wire antennas, such as inexpensive units
and car radios...
Active Antenna, easy to build - When
fate or nasty neighbours prevent you
from stringing a long-wire receiving
antenna, you'll find that this
pocket-size antenna will give the same,
or even better, reception. This "Active
Antenna"
is cheap to build" and has a range of 1
to 30Mhz at between 14 and 20dB gain....
Dipole Antenna - A simple dipole
antenna can be used for improved FM
broadcast signals. A dipole is basically
a length of conductor (wire) split into
two portions and signal is taken off at
the split. It has a nominal 3 dB gain
over an isotropic source and is
directional, tending..
E-field Circuits - If you place the
amplifier at the antenna, you avoid all
that cable capacitance but your
amplifier must have a correspondingly
higher input impedance to maintain flat
gain at the lower frequencies. For a
typical 10 pF antenna (about a meter
long) you would want a 100 megohm input
impedance to have flat gain down to 150
Hz! One simple solution is to add some
shunt capacitance across the antenna,
eating ...
Ground Pole Antenna - This Antenna
is most widely used all over the world.
For example, when you see a police car
it has a transmitter with Ground Pole
Antenna The body of car serves as
ground). It accepts load from 50 ohm
source and has larger power output than
Half-Wave Dipole Antenna...
Half-Wave Dipole Antenna (Open Dipole)
- It accepts load from 75 ohm source and
has much smaller power output than
Ground Pole Antenna. Use this antenna
only when you don't have GP Antenna.
Construction: Two aluminium rods ,each
of length "L" in meters are joined
together through an insulator as shown
in fig. From center, 75 ohm cable is
feeded just like ordinary TV antenna...
J-Pole Antenna - Tuned for 89MHz in
the FM broadcast band...
Medium Wave Active Antenna - This
circuit is designed to amplify the input
from a telescopic whip antenna. The
preamplifier is designed to cover the
medium waveband from about 550Khz to
1650Khz. The tuning voltage is supplieb
via RV2, a 10k potentiometer connected
to the 12 Volt power supply....
Pedestrian mobile HF antenna
Pi Section Coupler
Q Multiplying Loop Antenna
QRP Antenna Tuner
RF Amplifier for Ferrite Bar Antennas
Shorty Forty Antenna - Do you have
space limitation to put a 40 meter
dipole. Try this Compact 40 meter
antenna. .
Simple Dipole Antenna - It is very
easy to create a simple 1/2 wave dipole,
all you need is some lengths of wire
such as the core of some mains flex or
even a straightened out metal coat
hanger, some co-ax cable and a connector
for your scanners antenna input...
Small 915 MHz Antenna Beats Monopole
- EDN-Design Ideas: A 915-MHz
data-acquisition project required a
small antenna, but the available
antennas lacked the necessary
characteristics: efficiency,
compactness—that is, smaller than a
standard 3-in. monopole—with adequate
bandwidth, and with amenability to
modeling by inexpensive NEC-2 antenna
software....
Tesla Power Receiver
The ATL-3 Loop Antenna - All ATL-3
loop windings are centre tapped and
balanced w.r.t. their amplifier/receiver
chassis ground, and therefore electric
field interference pick up tends to self
cancel. Magnetic noise fields, e.g.
televisions and the electric meter box,
or electromagnetically radiated
interferences, may be minimised by loop
rotation....
The versatile end-fed wire - A piece
of wire of almost any length can be used
as an antenna on the HF bands. However,
just because an antenna can be made to
work is no guarantee that it will
perform efficiently. This article will
initially concentrate on the half
wavelength of wire and its use ....
TV/Radio Antenna Cable Galvanic Isolator
Unamplified Four Foot Box Loop
WIFI CAN Antenna - Got no dough for
a commercial WiFi antenna? Looking for
an inexpensive way to increase the range
of your wireless network? A tin can
waveguide antenna, or Cantenna, may be
just the ticket. This design can be
built for under $5 U.S. and reuses a
food, juice, or other tin can....
Windscreen loop aerial - If you do
not like the whip antenna on your car,
you may try this alternative circuit. A
one-turn loop is installed in the
windscreen of the car, keeping possibly
away from the metal structure of the
car. This loop is terminated in a 6.5mm
ring core suitable for VHF use...
Wireless Phono Oscillator - A "phono
oscillator" is a simple, short-range AM
band transmitter that was typically used
to send the signal from a phonograph to
a nearby radio, eliminating the need for
an amplifier and speaker. This version
uses only one transistor and...
Yagi Antenna - To improve signal
transmission or reception in specific
directions, basic elements, either
vertical or horizontal, can be combined
to form arrays. The most common form is
the Yagi-Uda parasitic array commonly
referred to as a Yagi array or beam. It
consists of a driven element which is
either a simple or folded dipole and a
series of parasitic elements arranged in
a plane. The elements are called
parasitic because they are not directly
driven by the transmitter but rather
absorb energy from the radiated element
and re-radiate it.
YAGI UDA Antenna |
