Powerful AM Transmitter

This is the circuit diagram of powerful AM transmitter which use ceramic resonator/filter of 3.587 MHz. Resonators/filters of other frequencies such as 5.5 MHz, 7 MHz and 10.7 MHz may also be used. Use of different frequency filters/resonators will involve corresponding variation in the value of inductor used in the tank circuit of oscillator connected at the collector of transistor T1.

1296 MHz RF Amplifier using NEC70083

Here the Radio Frequency (RF) amplifier circuit design for frequency 1296 MHz.

By using an NEC70083, this 1296-MHz amplifier delivers about 17-dB gain and around 1- to 1.5-dB noise. It is assembled on a G-10 epoxy fiberglass PC board. Use the layout shown because this is very important for correct performance.

UHF Signal Amplifier for TV

This is the circuit diagram of UHF Signal Amplifier for television device. It uses single transistor 2SC3358 as the main signal amplifiication component.

Radio Frequency Modulator Circuit

This is a circuit design diagram of Radio Frequency (RF) Modulator. Due to the power MOSFETs offer high power gain at both audio and radio frequencies, they are will be also very useful in many areas of radio-circuit design. For BF applications, a MOSFET's large safe operating area, VDS vs ID, protects it against damage from reflected RF energy. As a modulator, a MOSFET's transfer linearity aids fidelity. In the suppressed-carrier modulator, an RF signal is applied to the primary of transformer T1, whose secondaries provide equal-amplitude, opposite-phase rf drive signals to output FETs Q1 and Q2.

900MHz RF Amplifier based BFG480W

Circuit Diagram:

This is the circuit diagram of 900MHz RF amplifier built based transistor BFG480W manufactured by Philips. The circuit features low noise, good linearity performance and works well for high frequency application.

RF Power Amplifier: Theory, Design and Practice

This is a document that explains the design and development of power RF amplifiers applied in an Amateur Radio station. An amplifier may possibly necessary to build as much as 1500W of RF output power, the legal maximum in the United states.

40M Band RF Preamp with 3 Tuned Filters

This is the schematic diagram of 40M band RF preamp with 3 tuned filters. Above image is an experimenter's 40 Meter band front end for CW. This has a double-tuned filter and a low gain, lower noise RF amplifier. This is a great circuit for isolation of a product detector or mixer in a popcorn receiver.

VE7GC Popcorn RF Preamplifier Circuit

Right here is definitely an simple VE7GC Popcorn RF preamplifier by Dick Pattinson. The circuit utilizes a single tuned circuit at the front end and can connect straight to a mixer or product detector in a simple receiver project. Note how Dick provided adjustable RF gain control for this circuit in his Wee Willy project on this web page. In case you can not get Tak Lee green 10.7 MHz IF coils, most likely any other brand of 10.7 MHz slug tuned IF transformer would do the job.

6M RF Preamp using MPF102

This is the 6M RF preamp circuit, build using MPF102 N-Channel RF Amplifier. It really is pretty much like a 6M two-stage preamp that published in QST during the mid eighties. Doug truly favored the grounded gate FET for narrow band preamps. His published work is replete with good examples of them on just about every band. I assembled that amplifier and consider acquiring about 10 dB gain, that is all that I desired for the 6M direct conversion receiver working with a diode ring detector that I was developing. The fantastic feature of the amplifier is the fact that it integrates a band pass filter and preamp in one.

10M band 27MHz RF Amplifier based VN66AF

This is 10M band 27MHz RF Amplifier which based VN66AF MOSPOWER manufactured by Siliconix. VN66AF is an RF amplifier for 10m band frequency (26-30 MHz).

10W Linear RF Amplifier Circuit

This is the 10W linear RF amplifier circuit whish use 2SC2078 as the main component to power up the input signal. The circuit actually can delivers output signal up to 15W.

This RF amplifier circuit has a wide bandwidth range, from 1.8 MHz through to over 30 MHz. The drive level needed is only about 2 - 5 mW under 14 MHz, increasing to 10 mW at 30 MHz. You can therefore make a good QRP CW rig with nothing more than this PA and a simple crystal oscillator. I can achieve 12 watts out of mine using a 10-turn loop around my Grid Dip Oscillator! I can get over 15 watts from my Marconi signal generator, but above about 12 watts it is being over-driven an may not be very nice to look at on the spectrum analyser. The circuit was designed to be as clean as possible.

VHF RF Preamp 100-175 MHz with MAX2633

This is the diagram of VHF RF Preamp circuit 100-175 MHz with single chip MAX2633. The circuit can be used for the entire VHF broadcast and PMR band (100-175 MHz) which can be easily construct without any special test equipment. The grounded-gate configuration is inherently stable without any neutralization if appropriate PCB layout techniques are employed. The performance of the amplifier is quite good. The noise figure is below 2 dB and the gain is over 13 dB.

Low-Cost Broadband HF Amplifier based MOSFET IRF510

This is the circuit diagram of low-cost broadband HF amplifier build based MOSFET IRF510. The amplifier is built on double-sided PC board and requires no tuning. Another PC board contains the low-pass filters. Power supply needed for this RF amplifier is 28 V DC at 5 A, although the amplifier performs well at 13.8 V DC.

Several of these amplifiers have been built and exhibit similar performance. Al has been using his amplifier on each of the HF bands, logging well over 500 contacts in 18 months. Signal reports indicate a noticeable improvement in readability (about two S units on average) over his 5 W rig. No indications of instability, CW key clicks or distortion on SSB have been reported. To make it easy for you to duplicate this project, PC boards and parts kits are available, all at a cost of about $100!

12W RF Amplifier 88-108 MHz based RD15HVF1

This is the 12W RF amplifier circuit for frequency range of 88MHz to 108MHz (FM broadband). This new FM power amplifier is used the famous MOSFET RD15HVF1. We've chosen the synthesizer N°1 to drive this amplifier circuit. In fact, only 200mW are required to obtain the 12W output power level.

Class E RF Amplifier with 24 MOSFETs

This is the circuit diagram of Class E RF Amplifier which build using total of 24 MOSFETs. This high power RF amplifier covering the 80 and 160 meter amateur radio bands.

The amplifier is constructed in 4 of 6-MOSFET modules and applies IXDD414 digital gate drivers. Every gate driver drives 2 MOSFETs.

400W RF Power Amplifier with MOSFET FQA11N90

Here the 400W RF power amplifier circuit build using power MOSFET FQA11N90. This Class E RF amplifier will provide approximately 400 watts of RF output, depending on the input voltage and tuning parameters (current). The amplifier utilizes low-cost IXDD414 Driver ICs - one for each two MOSFETs. Transient Voltage Supressors (TVS devices) are applied on the gates, drain bus and modulated DC input towards the RF amplifier to secure the MOSFETs from damage because of accidental overvoltage. The carrier DC voltage ought to be between 40 volts and 50 volts, and not greater than 135 volts at full positive peak modulation.

VHF Preamplifier for FM Broadcasting 88MHz-108MHz (Band II)

Above schematic diagram is the circuit of VHF pre-amplifier for FM broadcasting (frequency 88MHz-108MHz, band II)

The circuit is working with two 2N3819 FET's in cascode configuration. The lower FET works in common source mode, while the upper FET, works in common gate, realising full high frequency gain. The bottom FET is adjustable allowing a peak for a particular station.

40W Wideband RF Power Amplifier 88 - 108 MHz based MRF171A

This is the circuit diagram of 40W wideband RF power amplifier 88 - 108 MHz build based MOSFET MRF171A. The purpose of this circuit is to boost the output power of low power FM broadcast band exciters, a number of these are available commercially, both as kits and ready made.

This design is based on a new MOSFET device, with the attendant advantages of high gain, high efficiency and ease of tuning.

8W FM RF amplifier 88-108MHz with BLV10

This is 8W FM RF amplifier for frequency range of 88-108 MHz with no tune broadband) needed to cover all the FM Band. The circuit use BLV10 as the main amplifier component. You need the 2N3866 driver stage to boost properly the BLV10 transitor.

Circuit diagram:

FM RF Amplifier 8 Watt based 2SC1971

The above design is very simple FM RF amplifier 8W Watt based 2SC1971 VHF power transistor. The RF Amplifier PCB layout designed for FM broadband 88-108 MHz transmitters using microstripline technique. This 8W RF amplifier circuit provides an appropriate power boost for transmitters with an input of 500 mW.

RF Amplifier PCB
The PCB outline is 77 x 56 mm use FR-4 double sided photoresist epoxy pcb material for best results.

RF Amplifier Construction
All SMD components are 1206 types. Connect the bottom layer (groundplane) on several points (through via's) with the top layer of the PCB.