RF Circuits
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This transmitter with a good antenna and under proper conditions of use may have a range of more than 45km. The configuration is made by the rise of the output lamp, which makes it advantageous as regards the fidelity of the emitted signal. The 6V6 lamp is used in the oscillation step. The coil L1 will be commercially available as a 6SA7 oscillator. Intermediate reception of L1 is associated with the 6V6 cathode. In the isolation stage, the... .
This transmitter works in the short waves from 6MC / S to 22MC / S. Coil L1 is the short wave oscillating coil of the 6SA7 lamp and you will find it ready for trade. Capacitor C1 is variable with a capacity of 0-500pF. The coil L1 consists of 13 coils 3cm in diameter and 1mm thick wire. Capacitors C1, C2, C3 and C4 are variables with a capacity of 0-500pF each. .
For our strong construction with the two 807 we do not need words. We all know the performance of such a machine. In this construction we have the peculiarity of high upward tension and independent coupling. On the output lamps, resulting in the output power being increased by several watts. We certainly will not talk about 130-150 watts, but we get 100 watts for sure. With an antenna of about 80 meters it can be heard at a distance of more... .
This transmitter consists of three stages. The step of the oscillator with the 6L6 lamp, the amplifier isolator with the lamp 807 and the final stage of the transmitter with the 811 lamp. The coil L1 is requested by the market as a coil of the 6SA7. The various RFCs are sold on the market and used to isolate the feed device from the generated radio frequencies. .
It consists essentially of three stages and gives the antenna a power of 300 WATT, provided it is properly tuned. The first tier is an oscillator that has an oscillating coil L1 that will be required by the market as a 6SA7 coil. The coils L2 and L3 consist of 60 coils of 1mm cross-section wire wound on a 5cm diameter tome so that they have some shots for better resonance, which is also done with the help of variable capacitors and ammeters.... .
This transmitter of 255W is depended on the coils we put at it to work in both the middle and the short waves. The power in the antenna is 255W and includes 4 states. The first consists of the EF80 that works as a COLLPITS CLAPP oscillator. Frequency selection is done in a somewhat unusual way: Instead of the variable capacitor, it uses a ferrite-sinking mechanical core system. The reasons we have chosen this way are: In the common variable... .
In this circuit, the wearer assembly consists of only one lamp, 6V6 or 6L6, which acts as an oscillator and as an output amplifier at the same time. Coil L1 is the medium wave oscillation coil. Of 6SA7. The coil L2 consists of 50 spools wrapped on a cylinder covered with a 3 cm diameter insulating material. The diameter of the wire is 0.5mm. The capacitor C1 is a double variable air of 1000pF (connect the two capacitors in parallel). C1 itself... .
Is this a transmitter? Medium-wave short-wave consists of three transistors. The transistor AF115, along with the rest of its circuitry, is the oscillator of the device. The circuit of the two OC72 is the low-frequency amplifier (modulator), which forms the carrier wave produced in the circuit of the AF115 lamp from its secondary transformer T1. The microphone is crystalline of small size. Transformer T1 is an adapter and has AD9014 data. .
This transmitter consists of 5 in total bulbs. 6L6 works as an oscillator. Subsequently the oscillation is guided to the guide grid of 807 which acts as the ultimate amplifier and is the transmitter output lamp. The amplifier consists of the ECC83 double-stage as pre-amplifier and 6L6. The power supply feeds both the transmitter and the modulator. 5R4 is used as a rectifier lamp. The coil L1 has been requested by the market as a coil of 6SA7... .
This transmitter, as shown in the drawing, consists of a 6V6 as an oscillator, then the signal excites an 807 which acts as a buffer. The final step consists of two 807 in Push-Pull. The amplifier consists of three in series double-triodes ECC83 and finally two 6L6 in Push-Pull. The transmitter uses two power supplies, which is why we use two more lamps to manufacture, 5U4 kai thn 5R4. The L1 coil will be purchased commercially as a 6sa7... .
This project is a construction of a VHF-UHF linear amplifier that can work at frequencies from 47MHz to 740MHz. It can be used as a final output stage of any transmitter working between these frequencies. It use the BFQ34 NPN a 4GHz wide-band transistor with excellent characteristics. The UHF (ultra high frequency) frequencies begin at 300 MHz and end at 3000 MHz (wavelength: 1m to 100mm). VHF (very high frequency) is limited between 30 MHz... .
This Jammer circuit can be used indoor or outdoor and the coverage/range that offers is about 30 meters in order to disconnect the wireless devices from their communication with the base station. In the circuit design, we use the frequency ranges reserved by mobile operators as well as the 2.4-2.5Ghz band that does not require Wi-Fi authorization. Let's look at the frequency ranges used by the four different generations of mobile phone systems. .
This amplifier is intended for amplifying low signals from oscillators in the FM band. It does not have frequency regulators with variable capacitors and coils, it has a wide range and moderate power capable of driving several linear amplifiers. The whole construction is based on the two low-power 2N4427 transistors, which are designed for the VHF range, and output up to 1W. The amplifier is used in cases where additional amplification is... .
This circuit is an amplifier for small transmitters operating in the UHF band, specifically in the 450-800MHz range. The amplifier works in class A and we used the well-known Philips BLW33 transistor for its manufacture. The construction, although simple, can be said to be quite critical due to the high frequency singularity. To achieve this, a double-sided printed circuit is required, where the lower face is used for grounding with... .
The simplicity of this transmitter compared to its very high performance makes it very interesting. Its output power is about 30 W and its range under normal conditions, with proper antenna and handling, reaches 30 km. The oscillator is the PL 84 which provides enough signal to normally excite the output light. Coil L1 is the oscillation coil of the 6SA7 lamp. The RFC1 has a 2.5mH inductance and can operate at a current of 100mA. The PL 509... .
The antenna tunning circuit can accommodate 1/2 wave length antennas or higher, for input resistances of 50 Ohms which make it suitable for CB (Citizen Band) transceivers. C1 is for fine tunning and C2 is just for tunning. Turning C3 with the help of C2 you can set the SWR to 1:1. The Coil L is made of 11 turns of insulated copper wire with diameter of 1mm.
This small circuit is a Linear amplifier for driving small UHF TV transmitters. Its gain is 7dB and can amplify a signal between 450-800 MHz. You can drive the circuit with 1 to 1,5 Watts signal. Better use double layer PCB with the second layer connected to earth. Use a stabilized power supply 25 volts and at least 5Amps.
TheCA3189E is a comprehensive FM-IF system designed for high fidelity FM tuners. It includes a three stage FM-IF amplifier/limiter configuration with level detectors for each stage, a double-balanced quadrature FM detector and an audio amplifier that features the optional use of a muting circuit. The advanced circuit design includes desirable special features such as delayed AGC for the RF tuner, an AFC drive circuit, and an output signal to...
This reciever uses the TDA1072A which is a complete AM reciever on a chip and it only requires comparitively few peripheral components to complete a high quality AM radio Circuit. Unlike some other AM radio ICs, a minimum number of external tuned inductors are used to preserve reasonable performance, selectivity and quality of output. Only two of these, an RF input transformer and a single winding oscillator coil need be tuned either...
An FM radio on a single chip requiring only a few simple peripheral components. In particular the ship requires only one simple coil and alignment is very easy. The chip includes an RF input stage, mixer, local oscillator, IF amplifier/limiter, phase demodulator, mute detector and mute switch. The output will directly drive a crystal earpiece or could be used with a TBA820M to form a complete portable radio.
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