Parallel 210 MOPA Transmitter


The inspiration of the Parallel 210 MOPA transmitter came from Ross A. Hull's September 1928 article on "The Oscillator-Amplifier Transmitter". The Master-Oscillator Power-Amplifier or MOPA's was becoming the preferred transmitter circuit of choice for the Ham in 1929 due to the introduction of new transmitter emissions regulations. The MOPA design was an attempt to create a stable transmitter tone. As long as the oscillating circuit provided a stable keying tone, the introduction of an additional amplifier stage reduced antenna loading and swinging effects on the transmitter frequency.





1929 MOPA Transmitter

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