Learning morse code is fun and exciting. At first, I don't see the importance of it thinking that this is just an obsolete form of communication. With the encouragement and help of my friends on the air, I was hooked with it and began to search different circuits about the morse code oscillator. I started with the 555 timer IC taken from my ARRL 1989 edition handbook but the audio quality of the oscillator was very irritating to my ears. This was due to the inherent square wave output of the 555 IC. Several search in the internet brought me the idea of constructing an audio oscillator that will generates a pure sine wave at 800Hz. In my project the circuit was the popular Bridge-T oscillator and then feeds to an audio amplifier to increase the output audio. The resulting output tone was nice and pleasant to hear as what the other station gives compliment to my oscillator.
The PCB board and the speaker were enclosed on an empty CPU power supply casing. On the side of the casing, my homemade straight key is mounted using a contact cement. The straight key was constructed using a hard disk motor. Kindly check the attachment for the oscillator circuit. ---73 de hevir
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