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Cheap and simple RF amp for signal generator

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New Member
I'm looking to build a low power (within legal limits) RF power amplifier that will alow me to connect my signal generator (as the carrier wave)
and a line-level audio input to make a simple AM transmitter.
Apparently I can just use an op amp, rather than a MOSFET because of the low frequencies involved?.

Can someone provide me with a circuit diagram and parts list?

Appreciated, thanks.

The Signal Generator:
Signal Generator Specs:
Output Voltage :5V Rms or more
Output Distortion :400 Hz - 20KHz, 0.1% or Less
(100 range for 1KHz)
50Hz - 500KHz, 0.5% or Less
Output Flatness :±1.5dB (refer to 1KhZ)
Square Wave Characteristics
Output Voltage :10V p.p or more
Rise Time : 0.25 us or Less
Duty ratio :50%± 5% (refer to 1KHz)
External Synchronization Characteristics
Range ±3% of Oscillator Frequency
Input Impedance : 10K Approximate
Maximum Input :10V Rms
Output Characteristics
Impedance :600Ω ± 10%
Attenuator: 0dB,-20dB, -40dB in 3steps (accuracy ± 1dB at 600Ω Load)


New Member
They all contain internal oscillators, which is not what I was asking for smarty pants. :)

I'm asking here because I have already searched google and not found a circuit that meets my requirements.

I would like to use my own 10Hz to 1Mhz signal generator as the carrier wave.


New Member
After a very quick scan this looks perfect.. accepts a carrier, input signal, does amplification, right frequency range.. all on one IC

Going to hunt around for some circuit diags now.



Well-Known Member
Another option is voltage controlled amplifer (VCA) circuits using op amps, where the modulation signal controls the gain and the carrier is the amplified signal. Would just have to be careful that the gain adjustment can follow the modulation rate of change.
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