Re: Analog keyer revisited #ubitx
I like this solution and I hope to give it a try out this weekend.
On 26/01/18 9:38 AM, John Pieper wrote:
I incorporated the keyer code from W0EB and W2CTX into my personal software build, but being determined to save the last analog input for S/power metering, kept the single input that detects three levels (four originally, but I don't care much about straight keying so I left that out for now). Some of the errors I've experienced and others have reported with the single line seemed to me consistent with the ADC deciding the state was "both" instead of "dit", for example an 'I' becoming an 'N' while the dit paddle is held closed. Looking at the nominal voltage levels with the provided resistors, I saw that there was only around 0.22 volts between the "dit" and "both" levels (1.60 vs 1.38 V). On the other hand, there is 1.8 volts between "dit" and "dah". Errors due to fluctuations would be much more likely between "dit" and "both".