RF Receiver Circuits
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Here`s a dual-band Regen that came from some encouraging emails from Jerry (K9UT) and another gentleman named Harvey, who built my original AGC-80, and its experimental "Regenerodyne" successor, the AGC-80/30. Jerry and I have corresponded on several.... -
Superheterodyne receivers have been mass-produced since around 1924, but for reasons of cost did not become successful until the 1930s. Before the second world war other, simpler receiver technologies such as the TRF receiver and the regenerative receiver.... -
Complete GPS solution using MAXIM CMOS RF front-end receiver MAX2742 and SONY GPS baseband CXD2932 is presented.... -
This application note explains the operation of the data slicers found in the Maxim line of UHF receivers like the MAX1470, MAX1473, and MAX1471 and transceivers like the MAX7030 and MAX7032.... -
An AM receiver relies upon the original carrier signal (station frequency) having been amplitude modulated. This means the original amplitude (strength) varies at an audio rate. Looking at figure 1 we can see an unmodulated carrier signal as it might be seen.... -
The regen is basically an oscillator circuit with a gain control that allows the user to adjust the feedback to a point just below oscillation or, quite often, just above the critical level such that a small oscillation is present. The typical regen uses a.... -
Integrated circuit Ul (an NE602 double-balanced mixer) is a combination oscillator and frequency mixer. Signals from the antenna input (at Jl) are fed through dc-blocking capacitor C1 to the RF-gain control, Rl, and fed to the input of Ul at pins 1 and 2..... -
The Demodulating Receiver (A3017) contains a 902 ’930 MHz 30-dB amplifier, a downshifer, a 60-dB 50-MHz limiting IF amplifier, a frequency discriminator, and an amplitude demodulator. The A301701A circuit board also includes, just for good measure, more.... -
This radio reciever can work with any of the following transistors zn414, mk484 or ta7642... -
Virtually all AM radio manufacturers used this exact circuit from about 1948 to 1963 or so. People are starting to collect these radios as antiques of sorts. I would be happy to credit the creator of this figure and caption, but I don`t recall from where I.... -
The schematic for this project flows naturally from left to right. Beginning at the antenna and the regenerative receiver front-end, then flowing through the amplification stages and then into the 555 timer. This is a very common regenerative receiver.... -
After the wizardry that is our standard renegerative front-end receiver circuit, we will be able to see some initial output receiver from our transmitter. The point in the schematic we`ll look at first is right after the LC tuning circuit and DC blocking.... -
This web page is a memorial to Mike Caughran, KL7R, who died suddenly in January 2007. Mike was a passionate experimenter who was embraced by the homebrew radio electronics community. He was best known as the co-creator of and sidekick to Bill Meara, M0HBR.... -
Low-cost CW superhet receiver with a 4. 00 MHz Intermediate frequency. There is no AGC or RF gain control, however this receiver has good large signal handling capability. This receiver uses just 6 bipolar transistors and an op amp for reasonable volume into.... -
By the addition of one integrated circuit and some passive components, I was able to convert my earlier developed 40-meter direct conversion receiver design into a superhet model. Anyone who has listened to 40 meters during the evening hours on the crowded.... -
For digital modes the ideal receiver must be very simple, front end selectivity, manually adjustable gain, IF filter. All the goodies you can find on the HF receivers can be done by software. In my junk box there were one surplus 1. 4 MHz, 3 kHz wide Xtal.... -
Basic Regen design is pretty common, so BEFORE the schematic comes the "concept stage", the "what`s available in the junkbox stage", back to the "concept stage", followed by the "mechanical/electrical layout stage", then sketch a rough schematic. and do it.... -
The schematic for the crystal bandpass filter/amplifier board appears below (left) withimages of the assembled and boxed unit appearing below center andright. The signal frequency bandpass filter isconstructed over a ground plane and housed in its own.... -
This little project arose from a desire to experiment with some of the more "traditional" methods of radioconstruction which enjoyed popularity some 70 years ago. I wanted to find out for myself what kind of performance could be achieved using simple.... -
One thing we should keep in mind is that the EC10 is now a vintage receiver, it has collector appeal. Any-thing we do should really be carried out in a manner that preserves the original state, most of the following adheres to this. Things like replacing all.... -
This is a detailed explanation of a procedure you can use to modify a UHF MICOR "M" range (450-470 MHz) receiver board so it operates adequately in the 435-450 MHz range. This is an enhancement to Kevin`s text-only article. These receivers are commonly found.... -
RF Cafe visitor David M. wrote to ask that I scan and post this article from the January 1963 edition of Popular Electronics. It is an article written by Philip Hatfield, of the Receiving Tube Department of General Electric that describe a very simple design.... -
Before starting on the receiver side of the` Chatterbox`, we ought to take a final look at the transmitter itself. The Chatterbox transmitter is built separately, because many constructors will want to use it in conjunction with an existing receiver on 1..... -
MRFICl505R2 is a 1. 575GHz GPS downconverter chip. It integrates mixer, VCO, PLL, crystal oscillator, A / D converter and loop filter and other circuits. MRFICl505R2 IF output frequency is 4. 1MHz; it has 105dB typical conversion gain, 2. 7V operating.... -
This circuit is used in impulse speed modulation system. In this system, transmitter change impulse speed of modulated beam in optical fiber, let it change around 50kHz center frequency. L14G2 optical transistor convert molulated light to radio-frequency.... -
This receiver covers 8.5 to 11.5 MHz in two bands and has a sensitivity of under 1 ?V. Nn NE602 mixer feeds a 455-kHz IF amplifier (Q1 and Q2), detector D4, and audio amplifier IC2. Q4 serves as an AGC amplifier coil data is given in the table. The LO is.... -
Integrated circuit U1 (an NE602 double-balanced mixer) is a combination oscillator and frequency mixer. Signals from the antenna input (at J1) are fed through dc-blocking capacitor C1 to the RF-gain control, R1, and fed to the input of U1 at pins 1 and 2.The....
New Circuits
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This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of.... -
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.... -
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.... -
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.... -
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.... -
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,.... -
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.... -
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.... -
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.....
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