QRP Labs QCX-mini, Assembly Instructions Manual

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straight through from the key input, to the key output control line – but in other modes the
processor must generate the keying signal.
The component values set the rise and fall time. With the components shown, the rise and
fall time is about 5 milliseconds.
The following oscilloscope screenshots show a 40m band (7MHz) transmission, keyed with
a continuous series of CW dits at approximately 24 words per minute. The amplitude is
approximately 3.8W into a 50-ohm dummy load (with 12V power supply).
4.13 Microcontroller
The ATmega328 microcontroller circuit controls many aspects of this transceiver. Below is
this section of the transceiver circuit. Several points are worthy of discussion.
QCX-mini assembly Rev 1.05_Fr
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