Harry Dalek wrote:I was thinking why not a 4066 for passing signals..
I did consider using a 'HC4053 which rather unusually for a logic chip can handle positive and negative signals. It requires +5V, 0V and -5V for power in that case. But there are some concerns with isolation at high frequencies, i.e. the signal can 'leak' into the 'off' input or output. This would be worse if using the higher frequency AD chips, the 40MHz AD9850 or the 70MHz AD9851. Not that I really have a need for them.
As for what this is for? It's a tool, same idea as a multi-meter or 'scope, it can be used on anything that needs a signal. My existing signal generator is fading fast, but it is 30 years old.
Being remote controlled (at least in frequency and waveform) it could be used as a modulator for SSTV, but that's overkill. My existing SSTV modulator uses a small 8-pin PIC micro and a handful of other components.
It is as the title says, "A Useful General Purpose Oscillator." But it can go down to some ridiculously low frequencies, ideal for testing NBTV stuff. The lowest frequency it can generate is 0.093Hz, or one cycle in 10.75 seconds.
Steve A.
I'm thinking of adding a 'B' (Binary) input mode. This would be the raw binary value of the output frequency, mainly useful with those extreme LF signals. Or perhaps a 'H' (Hex) mode for similar reasons, but maybe both/either of those sometime later...