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 Post subject: Re: BUILD AN AM TRANSMITTER FOR USE WITH ANTIQUE RADIOS
PostPosted: Sep Tue 21, 2021 1:40 am 
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Joined: Mar Thu 01, 2018 1:30 am
Posts: 803
In this TX, 100% modulation was obtained by modulating the oscillator. The extra coils RFC 3 and 4 are added to store additional energy. The oscillator's output is taken via a 2.2K load and feeds a small linear amplifier built around 2n7000 mosfet. The oscilloscope shows 100% modulation with room to spare! It would work with medium wave crystals too. VR2 sets the standing current of 10 to 15ma to follow the 100mW input power rule of final stage.


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