There are still neighbors that keep annoying you by having loud the TV or the radio? Well I have you the solution. In fact all neighborhood will face your jamming waves at their TVs and radios, so be careful. This Jammer is the improved version of the old "TV and FM jammer schematic" with the difference of much higher power. Many of you where asking for a stronger and wider effect but to be as portable as can be. Looking at the schematic you can see that, only the.....
This transmitter can be used for transmitter hunts, for remote key finding, or for radio telemetry in model rockets. It can be tuned to the two meter band or other VHF bands by charging Cl and Ll. 11 is four turns of #20 enameled wire airwound, 0.25 inch in diameter (use a drill bit), 0.2 inch long, centertapped. The antenna can be 18 inches of any type of wire. IC2 functions as an audio oscillator that is turned on and off by IC1 about once per second. ..
This field strength meter consists of a tuned crystal detector producing a dc output voltage from a transmitted signal. The dc voltage is used to shift the frequency of a transmitter of 100-mW power operating at 1650 kHz. The frequency shift is proportional to the received field strength...
This low-power video transmitter is useful for R/C applications, surveillance, or amateur radio applications. Seven transistors are used in a crystal oscillator-multiplier RF power amplifier chain, and a high-level video modulator. A 9- to 14-Vdc supply is required. ..
Used for digital control of musical instruments, this transmitter converts the digital data signals to equivalent optical signals for fiberoptic cable interface. Optocoupler IC1 provides isolation, and drives IC2-a and -b and Tl,..
Although theIR region is free from radio interference, it is subject to interference from incandescent lamps, fluorescent lamps, stray reflections, and other sources. A simple way to overcome that problem is to create a carrier by chopping the IR radiation at a rate of 100 kHz. The audio then modulates the carrier by modulating the chopping rate. A receiver then detects the IR beam as a 100-kHz FM signal. ..
This receiver consists of an input network amplifier IC7 FSK PLL detector ICG, and output am..
A sidetone oscillator is a special audio astable multivibrator. Keying is accomplished oscillator that is turned on and off with the by applying a positive dc potential, developed transmitter. The oscillator is rf-driven and bat- from the rf signal, to the reset terminal of the tery operated..
To display an rf signal, connect LI to the transmitter and points A and B to the vertical plates of the oscilloscope. Adjust LI for minimum SWR and C3 for the desired trace height on the CRT..
This circuit provides interferenced rejection for the CW operator. The 567 phase-locked loop is configured to respond to tones from 500 to 1100 Hz. The Schmitt trigger reduces the weighting effect caused by the output of the PLL remaining low after removal of the audio signal. Ten to 15 millivolts of audio activate the circuit..
That RF Amplifier is for boosting small fm transmitters and bugs. It use two Philips 2N4427 and its power is about 1Watt. At the output you can drive any linear with BGY133 or BLY87 and so on. Its power supply has to give 500mA current at 12 Volts. More voltage can boost the distance but the transistors will be burned much earlier than usual.! In any case do not exceed the 15Volts. ..
Fiber Optic applications require analog drivers and receivers operating in the megahertz region. This complete analog transmission system is suitable for optical communication applications up to 3 MHz. The transmitter LED is normally biased at 50 mA operating current. The input is capacitively coupled and ranges from 0 to 5 V, modulating the LED current from 0 to 100 mA. The receiver circuit is configured as a transimpe-danee amplifier..
The NE564 is used as an FM demodulator. The connections for operation at 5 V and 12 V are shown in Figures 21-4A and 21-4B. The input signal is ac coupled with the output signal being extracted at Pin 14. Loop filtering is provided by the capacitors at Pins 4 and 5 with additional filtering being provided by the capacitor at Pin 14. ..
This wideband antenna preamplifier has a gain of around 20 dB from 40 to 860 MHz, covering the entire VHF, FM, commercial, and UHF bands...
The ultra-simple one-transistor, IR transmitter shown is designed to transmit the sound from any 8 or 16 ohm audio source, such as a TV, radio, or tape recorder on an infrared beam of light. ..
This locater is made up of two parts. The first is an rf oscillator, whose circuit is shown in Fig. 8-4a. The second is a sensitive receiver shown in Fig. 8-4b. The heart of the oscillator is a 555 timer !C. Tank circuit C2 and L1 is used to tune the transmitter. The antenna is coupled to the transmitter through C3. A telescopic antenna or a length of hookup wire will work quite well. At the receiver, the incoming signal is tuned by C5 and L2 before being passed on to.....
An LM311 comparator converts a small analog signal to a digital level for the DC4046 phase-locked loop, which is configured as a first-order FM demodulator. This demodulator works with a 50-kHz FM modulated input signal. It has applications in FM light beam receivers or in remote control applications...
Pulsed sound is produced by this circuit. Ul is used as a bistable multivibrator, which acts as a contact "debou..
This tracking transmitter consists of four distinct subassemblies; a free-running multivibrator, a transmit switch, an audio-tone generator, and an FM transmitter. The multivibrator (which produces a pulse width with a pulse separation of 1500 ms) is built around Ql and Q2. The multivibrator output is coupled through R5 to the base of Q3, whose emitter feeds Q4, ..
In This application, a BA1404 is used to generate an FM MPX baseband signal. This modulates a crystal oscillator (Q3) via a dual varactor series modulator. ..
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