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RF Transmitter Circuits
RF Transmitter Circuits
Quality FM-TV micro transmitter 40-200 Mhz
This Transmitter can be powered by a battery 9V (not more than 12V). You can connect your music source where the microphone is or use a simple condenser microphone. The range of signal can reach 400 meters in open air. The wide range of frequency is up to you. Tune it at FM band (88-108) or TV band 40-80Mhz. Play with the Coil and the variable...
4 ~ 20mA transmitter circuit diagram TMP35 temperature
4 ~ 20mA constituted by a TMP35 temperature transmitter circuit as shown in FIG. This circuit can be a voltage signal TMP35 output is converted into a standard 4 ~ 20mA current
MC2833 radio transmitter Typical application circuit
MC2833 MC2831 radio transmitter dedicated circuit is improved.Radio transmitter typical application circuit this circuit generates a high frequency 49.7MHz signal transmitted by the antenna out.
1-2 MHz radio transmitter circuit diagram
A circuit diagram of the T1 is a low-impedance output transformer, it comes with 5000-8 ohm resistor.
500KW Transmitter Schematic
The transmitter was designed with redundancy and cutback (reduced power mode) in mind, giving the transmitter more continuity of service. The final amplifier was divided into 3 separate modules, each using four RCA type UV-898 tubes in push-pull parallel making up a total of 12 output tubes. The outputs of the three modules were combined in...
VHF/UHF TV modulator
A 'TV modulator' is really no more than a transmitter. It is a very small transmitter, admittedly, but none the less that is what it is. What does a modulator actually do? In general -and this design is no exception to the rule - it is a simple oscillator that generates a frequency somewhere in the VHF or UHF region. The oscillator is modulated...
Video/Audio Wireless Transmitter
In this fast-paced world, there is little time for inconveniences and a greater need for portability and adaptability. The idea for an Audio/Video transmitter stems from this need. There may have been times when you`ve wanted to hook up your VCR from one room to another television set in another room. But that would have entailed that you first...
80 Watt stereo transmitter
This transmitter was designed from the ground up to provide very high sound quality, coupled with excellent frequency stability, reliability, etc. It can be used as a standalone transmitter to serve a medium-sized town, or as an exciter to drive a kilowatt-class power amplifier to serve a large city. It is designed to work from 13.8V nominal...
A 40 meter QRP - Transceiver
This was one of my very first transceiver developments. This page was also one of the very first circuit descriptions that I put on the internet quite some years agon. Today I would not build a transceiver like I did then, but it was working, so I have kept this page for historical (and sentimental) reasons. If you are a beginner in building you...
AM DSB TRANSMITTER FOR HAMS
The circuit of AM transmitter is designed to transmit (amplitude modulated) DSB (double side band) signals. A modulated AM signal consists of a carrier and two symetrically spaced side bands. The two side bands have the same amplitude and carry the same information. In fact, the carrier itself coveys or carries no information. In a 100%...
Ceramic Filter Beat Frequency Oscillator
BFO is a simple device which helps us to listen SSB and CW transmissions. Reception of SSB and CW signals requires a product detector or BFO (Beat Frequency Oscillator) to reinsert the missing carrier. This circuit is very simple since it requires no turned circuit and hence no adjustment in the BFO circuit. The number of components required is...
Circuit transmits ARINC 429 data
The physical transmission medium for the 429 standard is 78Ω shielded, twisted-pair cable that uses a complementary, differential bipolar RZ (return-to-zero) waveform (Figure 2). The voltages are the net differentials that the biphase drive develops: For example, the differential is 10V when you drive the Data A signal in Figure 1 to 5V and the...
ATV Repeater System Exciter
The ATV exciter described here uses a pair of Hamtronics model TA451 2-watt narrow-band FM voice transmitters to develop video and audio carriers on 439.250 MHz and 443.750 MHz. The TA451 is a single board, phase modulated exciter designed for amateur radio and commercial two-way land-mobile radio service. Several circuit modifications were made...
Ham Radio BFO
Ham Radio (amateur radio) is a popular hobby amongst electronics enthusiasts all over the world. Basically the hobby involves a person in making his own gear consisting of a receiver and transmitter or a transceiver (a receiver and a transmitter in one unit) after procuring a licence from the Ministry of Communications. Home brewing or self...
Miniature MW Transmitter
Here is a very simple, inexpensive and interesting project which provides lot of fun to a home experimenter or hobbyist. This simple transmitter can transmit speeches or songs within a short range. The circuit uses only one transistor. The entire circuit can be easily assembled on a prototyping printed circuit board. After assembling all the...
MULTIBAND CW TRANSMITTER
A radio frequency oscillator is at the heart of all radio transmitters and receivers. It generates high frequency oscillations, which are known as carrier waves. Here's a continuous wave (CW) transmitter for transmitting Morse code signals in the shortwave band (see Fig. 1). It is basically a variable frequency oscillator (VFO) whose frequency...
RF-telemetry transmitter features minimal parts count
The circuit in Figure 1 meets these criteria and uses only three off-the-shelf ICs and a few passive components. Although dedicated to conditioning the low-level signal a strain-gauge bridge produces, the circuit can operate with almost any resistive transducer based on a Wheatstone bridge. The circuit comprises a VFC (voltage-to-frequency...
This transmitter circuit operates in shortwave HF band (6 MHz to 15 MHz), and can be used for short-range communication and for educational purposes. The circuit consists of a mic amplifier, a variable frequency oscillator, and modulation amplifier stages. Transistor T1 (BF195) is used as a simple RF oscillator. Resistors R6 and R7 determine...
Small circuit forms programmable 4- to 20-mA transmitter
One of the key challenges in the design of 4- to 20-mA current transmitters is the voltage-to-current conversion stage. Conventional transmitters use multiple op amps and transistors to perform the conversion function. These approaches have been around for a long time, but they are usually inflexible, have poor power efficiency, and have limited...
4-transistor tracking transmitter
Sorry, I don`t have any data/instructions for use on this schematic. If anyone knows how this circuit works or is used, please drop me an email at click here or use the feedback form.
GSM Automatic Meter Reading
GSM based Automatic meter reading, or AMR, is the technology of automatically collecting data from energy meter and transferring that data to a central database for billing and/or analyzing. The Transmitter is connected to the meter and it counts the pulses from it and displays it over the LCD display. It also transmit the data over RF to the...
1.5v tracking transmitter
The circuit is a common form used in FM transmitters. The transistor conducts for 60-90 electrical degrees. When it turns off the LC tank `rings`, completing the sinusoidal waveform coupled to the antenna. The circuit is 77-85% effecient, compared to 40-50% for a linear oscillator.
This is a 40 meter transmitter which uses two valves, the 6AU6 and 6GV8. The construction is easy. Just be carefull due to high voltage present.
1.5 Watt FM Transmitter
P1 act as condenser microphone volume level. For FM, coil will be small. Use thin gauge enamel magnet wire. the diameter of coil will be a couple mm: use ink tube from pen to form, and try 8-12 turns. Small inductance coils make for much guess work. Tags: 1. 5 watt fm transmitter, circuit diagram fm transmitter, circuit diagram of fm transmitter, f
ATV repeater controllers
This is an image Schematic. No Description available.
Automatic Retransmitting Makeshift Repeater
This circuit will be of interest to the radio amateur and anyone posessing two radios, (one of which must be able to transmit i.e. a transceiver). It is a self powered (audio derived) repeater circuit for receiving a signal and re-transmitting it via the other radio. This little circuit can turn two hand-held radios into a makeshift repeater....
LF Exciter using I2PHD/IK2CZL JASON
The unit described here is simple to build, and can be quite small. The picture below shows the prototype, in a box 175mm wide, 210mm deep and 55mm high. The single circuit board is 140 x 90mm, so there's plenty of room inside for another board (a local control and LCD display board is planned). The design includes a linear amplifier, sine wave...
1watt AM/CW 10-meter band transmitter
In this project, you will make a simple 3-stage low-power broadcast-type circuit, using a crystal oscillator integrated circuit and an a collector modulated AM oscillator with amplifier. You can connect the circuit to the an electred microphone or amplified dynamic microphone. Using an electred microphone is shown (in gray) in the diagram below....
AM/cw 20-meter band transmitter
In this project, you will make a simple low-power broadcast-type circuit, using a crystal oscillator integrated circuit and an a collector modulated AM oscillator. You can connect the circuit to the an electrec microphone (pointed out in gray on the diagram) or amplified dynamic microphone (no amplified microphone has a to low output voltage to...
AM/cw 10-meter band transmitter
In this project, you will make a simple low-power broadcast-type circuit, using a crystal oscillator integrated circuit and an a collector modulated AM oscillator. You can connect the circuit to the an amplified microphone (no amplified microphone has a to low output voltage to work. at least 100...200mv is needed). You could also add a LF...
AM/cw 12-meter band transmitter
CW is the simplest form of modulation. The output of the transmitter is switched on and off, typically to form the characters of the Morse code. CW transmitters are simple and inexpensive, and the transmitted CW signal doesn`t occupy much frequency space (usually less than 500 Hz). However, the CW signals will be difficult to hear on a normal...
HI-FI Stereo Encoder / Multiplexer
This stereo encoder is the perfect solution for those looking for a high quality stereo sound transmission at a low cost. This stereo encoder produces an excellent crystal clear stereo sound and very good channel separation that can match with many more expensive stereo encoders that are available on the market. It is all possible thanks to a...
FM Radio Circuits
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Ultrasonic distance finder circuit
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is measured. There are three main categories of distance measurement methods in use: a) By...
Simple Metal detector circuit with CD4030
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to find something potentially valuable, hidden a few centimeters below the soil. So many...
Fully automatic watering circuit for flower pots
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This circuit comes as a solution to this problem. Depending on humidity of the pot at...
Simple deep searching metal detector circuit
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the circuit of this metal detector, it is possible to detect a metal coin in depth of 90 to...
Sub-Harmonic Bass Converter for Electric Guitars
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound, such as filtering or distortion. Instead, a frequency division system produces outputs...
Echo Depth Sounding Sonar for Boats
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the calibration of the rope. This arrangement still exists in some yachts. The big...
100W HiFi Audio Amplifier Circuit
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power supply must be symmetrical so that no electrolytic capacitors are needed at the outlet....
Plant-Pot Water Level Indicator Circuit
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower. The circuit of the device is shown in Figure 2. The water detection is made from the bottom...
Analogue Sound Preasure dB-Meter Circuit
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to have a good accuracy we will get the limits of 20Hz to 20KHz. A sound to be heard does...
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