2 Channels RF Remote Control-Transmitter Receiver

This RF remote control is useful to handle some electric device. If you want to control your garage door, the only way is to use some RF remote control. The transmitter-receiver circuit use few components and ordinary. It's easy to build it because you don't have to tune-up any coil or variable capacitor. The RF modules are fix to work in...

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8W Broadband RF Amplifier 2SC1971 88-108 MHz

Here's a broadband FM RF amplifier using 2SC1971 VHF power transistor. The RF Amplifier PCB layout designed for FM broadband 88-108 MHz using microstripline technique. This 8W RF amplifier circuit provides an appropriate power boost with an input of 500 mW.RF Amplifier PCBThe PCB outline is 77 x 56 mm use FR-4 double sided photoresist epoxy...

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Classic RF Probe using 1N34A Diode

One of the handiest accessories you can have around the shack is RF Probe. It can be used to measure RF voltage (and power), trace RF signals in a new design, and troubleshoot malfunctioning RF circuits. This RF probe is easy to build.Complete Classic RF Probe SchematicFor best probe accuracy, size the resistor to match your DC Voltmeter's...

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BAS70 RF Probe Circuit

This RF probe is useful for small RF power levels up through the microwave frequency bands, and simply connects to your DVM (Digital Volt Meter). The voltage shown will not be accurate, since this is a rectifier probe (diode probe), but the measurements are good enough for you to be able to determine where the RF stops, or if a stage is...

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4 Ports Power Splitter 2.4 GHz

Here is a device called a power splitter (divider/combiner). You can use this to phase four antennas together for increased gain or combine the input/outputs of amplifier for increased power.This 4 to 1 (4-1=4 ports) power splitter work at 2.4GHz. You will use it for stack 4 pieces of 2.4 GHz helical antenna for get 6 dB more gain on AO-40...

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RF Field Strenght Meter with Attenuator up to 200 MHz

The RF field meter unit will be in great help to tune transmitters for best performances. You can measure the radiated energy field and can easy tune the system for max output field strength (maximum power).RF Field Strength SchematicThis field strength meter with selectable attenuator. You can used it for measuring the antenna gain and pattern,...

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100W RF Power Amplifier 50 MHz 2SC2782

This is a 6m band RF power amplifier (50 MHz) with 100W output. It used with my FT-736R and drive from 10W for the 6m SSB DX. The Building information comes from Japan CQ Magazine. The Toshiba RF bipolar power transistor will be used in it. RF Power Amplifier Schematic and PCBGroundingIf you want to construc this rf amplifier, it's the better...

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80W RF Amplifier 2SC2782 88-108 MHz

This is a RF power amplifier design using 2SC2782 bipolar transistors in a tuned class C circuit. The amplifier can be driven to full power with less than 1 watt driving power, so that a large gain margin results in this FM transmitter.To obtain stability in this rf amplifier, I employed several techniques, such as placing the resonances...

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RF Power Amplifier Module S-AV10H TOSHIBA

Here's an interesting S-AV10H TOSHIBA RF Power Amplifier Module circuit. It can deliver over 14W with as low as 100-200mW input power. The system is tuned for 50 ohm input and output. The frequency can be 150-175MHz. This is how the Module looks like.To the left is the power input pin. Then comes power control, main power line and to the...

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Simple RF Field Meter

This circuit is a simple RF field meter. It will be in great help to tune transmitters for best performances. Not everyone has a power meter, and how can you know that the antenna you connect is purely 50 ohm. The next block diagram show you one easy way to measure the RF field strength. To the left you find a dipole antenna.The antenna should...

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1W VHF RF Amplifier 2SC1970 88-108 MHz

This RF power amplifier is based on the transistor 2SC1970 and 2N4427. The output power is about 1.3W and the input driving power is 30-50mW. It will still get your RF signal quit far and I advice you to use a good 50 ohm resistor as dummy load. To tune this amplifier you can either use a power meter/wattmeter, SWR unit or you can do using...

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28W RF Amplifier for FM Broadcast 88-108 MHz 2SC1946

This RF Amplifier designed for FM broadcast using a single 2SC1946 VHF Power Transistor. This 10-30W RF amplifier circuit provides an appropriate power boost with an input of 1-3 watt. Tower are 30 meters high will send signal surrounding air should be around 15 km.RF Amplifier ArtworkThe layout of the 2SC1946 28 Watts FM broadcast RF amplifier...

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20W VHF Linear Amplifier 2SC1946 50 MHz

This VHF linear amplifier works for 50 MHz frequency using 2SC1946A with power output about 20 Watt. It needs input 30mW and output 25W for 150 Mhz. It seems can be used for 144 Mhz without modification. There are Power IC and 2SC1946A with low-pass filter on the board.Some Experiences I have checked Mitsubishi Catalogue and found it is 175...

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