HF Bands QRP RF Linear Amplifier based power transistor 2N5590.
This is a rather unusual QRP power RF amplifier design, with a wide frequency response; within three dB's from 300KHz to 30MHz. Overall gain is in the region of 16dB and the final output power may be well over four watts.
The wide bandwidth is a result of the construction of the RF transformers, T1 and T2. These are wound on 2-hole ferrite balun cores as commonly found in the old fashioned valve TV sets (e.g. Phillips 4322-020-31520). Twist 2 lengths of 22 SWG enamelled wire together and wind as shown. Connect the end of the "A" winding to the start of the "B" winding. Use this junction as the centre-tap of the transformer.
This PA will deliver 4 watts continuously (with a suitable heatsink), and may be loaded into a short-circuit or open circuit without causing damage. This makes it almost the ideal PA for outdoor/field use. Above is the full circuit diagram of the RFPA and the coil winding pattern. This PA may be used for for SSB, as well as CW (and AM?).
Set RV1 to MINIMUM resistance and apply 12volt power supply with NO DRIVE. Adjust RV1 for about 250mA DC total supply current. This may be be reduced to a much smaller current if lower output powers (reduced drive) is used.
About RF Amplifier
An RF power amplifier is a type of electronic amplifier which is utilised to convert a low-power radio-frequency signal into a larger signal of significant power, usually for driving the antenna of a transmitter. It is usually optimized to have high efficiency, high output Power (P1dB) compression, good gain, good return loss on the input and output, and optimum heat dissipation.
The basic applications of the RF power amplifier include driving to another high power source, driving a transmitting antenna, microwave heating, and exciting resonant cavity structures. Among these applications, driving transmitter antennas is most well known.
More explanation about power audio amplifier can be found at wikipedia.org
This is a demonstration about 01A RF Amplifier which is build used old tube component to amplify the signal. An RF power amplifier is a type of electronic amplifier which is utilised to convert a low-power radio-frequency signal into a larger signal of significant power, usually for driving the antenna of a transmitter. It is usually optimized to have high efficiency, high output Power (P1dB) compression, good gain, good return loss on the input and output, and optimum heat dissipation.
The basic applications of the RF power amplifier include driving to another high power source, driving a transmitting antenna, microwave heating, and exciting resonant cavity structures. Among these applications, driving transmitter antennas is most well known.
More explanation about power audio amplifier can be found at wikipedia.org
Watch the video:
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