One Watter: Phases Two and Three

I continue my build of the 15 meter One Watter by Diz and Chuck Adams:

Phases Two and Three
I have taken Chuck's Phase Two and Phase Three and combined them into this post. Basically, he has you build then keyer circuit and install and test the chip. Additionally, the transmit keying circuit and receiver muting circuits are tested.

Project schematic completion.

Audio and keyer circuits.

Whole board including the keyer circuit and muting circuit.

While these two phases sound impressive and you'd figure that the testing would be extensive but it's really quite simple. Here, Chuck powers up the board WITHOUT a new chip inserted in a newly built section and tests for the proper DC voltage at the appropriate IC socket pin. This is also important because there are three types of voltage regulators in this project: a 78L05 for the audio circuit, two 78L08s for the receiver mixer and transmitter, and a 78L10 for the VXO and it allows you to double check that the regulators are installed in the proper places.

The Phase Three checkout involves setting the keyer into straight key mode and then keying the unit and measuring various places around the board to see it the keying circuit sends +12 volts when keyed.

Up next is Phase Four which tests the newly constructed demodulator to see if you can get an 8,064 kHz signal through U6 into the audio chain.

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