27 MHz FM Receiver - The FMR-201 is a crystal controlled single channel receiver, comprising
of receiving, decoding and open collector output sections. . . .
27MHz/ 49 MHz Walkie Talkie - Lots of people are requesting walkie-talkie and RF remote control
schematics, so here is some. Building these circuits needs special equipment and expertise in RF circuits. If
you are going to experiment with these circuits, please. . . [Peter Jakab, Electrical Engineer, Engineer of
4 Transistor FM Receiver - This is a pocket sized receiver I built in 1994. The idea was to make a
simple but useable receiver running off 3V. My previous 6 transistor receiver was more bulky, requiring 12V.
This meant 10 x AA cells. I designed and made a PCB, . . . [email designer: cablehack at yahoo dot com]
6 Transistor Super Regen Receiver - Solid State Superregenerative Receiver. This is the only solid state
super regen design with more than 20uV sensitivity on FM that I know of. . . . [email designer: cablehack at
yahoo dot com]
70-120MHz FM Receiver - This simple one chip FM receiver / TV tuner will allow you to receive
frequencies from 70 up to 120MHz. With this small receiver it is possible to pickup TV stations, entire 88,
108MHz FM band, aircraft conversation and many other private transmissions. . .
AN-146: FM Remote Speaker System - Application Note. . . [National Semiconductor]
Feedback FM Receiver - . . .
FM Band Monaural Transmitter - A high quality monaura FM transmitter is quite useful in a variety of
applications. The audio from a TV or entertainment system may be transmitted for remote or portable listening
and for wireless earphone listening. The audio from an AM receiver placed near a window can be retransmitted
within a metal building where AM reception is not possible. Two transmitters will convert two portable. . .
[Copyright © 1998 Wenzel Associates, Inc.]
FM Band PreAmplifier - Here is a high performance RF amplifier for the FM band which can be
successfully built without any special test equipment. The grounded-gate configuration is inherently stable
without any neutralization if reasonably good layout techniques are employed. The output transformer is
designed to resonate with the FET's drain capacitance at about 92 MHz giving the amplifier the highest gain
at the low end of the band where the weaker stations operate. No tuning capacitor is needed as long as the
transformer is built precisely as described . . . [Copyright © 1998 Wenzel Associates, Inc.]
FM Booster - . . .
FM bug - Schematic only, no circuit description. . . [Designer's name not given]
FM bug 420-480 MHz - How about getting that old Nokia phone out of your drawer and turning it
into something freakishly cool? I will not lie to you, you will need a few tools and skills such as
soldering/desoldering and making PCBs. Here you can download Sprint-Layout. . . [designer's name not
FM Bug-transmitter - The circuit consists of two separate stages. The first is an audio
pre-amplifier and the second is a 90MHz oscillator. The first stage is very simple to explain. It is a
self-biasing common-emitter amplifier capable of amplifying minute signals picked up by the electret
microphone. . . [kit is designed and manufactured by TALKING ELECTRONICS]
FM Microphone - Here is the super NEW miracle improved "Frequency Modulation Wireless
Microphone" (BUG) with added easablilty, readability and copyability. This was necessitated after the number
of E-Mail questions posed by people who were confused by the layout of the project (s). Before proceeding
with the interesting bits, please note. . . [from Harry Lythall's website]
FM Microphone - A micro-transmitter is so small and sensitive, it have only 8
easy-to-get parts and can be assembled in one hour. . . . [designed by Jose Pino]
FM Oscillator - ASCII format. . .
FM Portable - . . .
FM Radio Microphone
with Internal Loop Antenna (Area 50)
- This article began as a design guide for hyper cranial erogenic field generators, however, your primitive
earth brains are completely unable to respond to erogenic fields in the 100MHz region. I personally had a
brain upgrade (for purely medical purposes of course) so I am able to respond. . . [Copyright © 1998 Wenzel
FM Radio Receiver - Frequency adjustment is accomplished with BB105 varicap diode. . .
FM Radio Transmitter - This small transmitter uses a Hartley type oscillator. Normally the
capacitor in the tank circuit would connect at the base of the transistor, but at VHF the base emitter
capacitance of the transistor acts as a short circuit, so in effect, it still is. The coil is four turns of
18swg wire wound around a quarter inch former. The aerial tap is about one and a half turns from the supply
end. Audio sensitivity is very good when used with an ECM type microphone insert. . . . [David Sayles'
circuit on Andy Collison's website]
FM Radio Transmitters with Opamp - An low power FM Transmitter using an op-amp as the audio preamp and a
single transistor as the RF amplifier. . . . [Designed by Kamran Ahmed]