[sdiy] Pulser & Ring Mod PCBs from by Music Easel adaptations available; New Year's Eve Special

[lanterma at ece.gatech.edu]

On Jan 16, 2011, at 12:53 PM, Dave Leith wrote:

> I have a question about the pulser board. Does the cv output
> (downwards ramp) maintain a sawtooth ramp (1) shape at the faster
> speeds or does the top flatten out (2).
> 
> 1, Normal cv (subaudio rate)
> .           .            .            .
>   .        .   .        .    .       .   .
>      .     .      .     .       .    .      .
>         .  .         .  .          . .         .
>            .            .            .            .
> 
> 
> 2. does one get higher speeds like this?
> ....        ....         ....         ....
>   .        .   .        .    .       .   .
>      .     .      .     .       .    .      .
>         .  .         .  .          . .         .
>            .            .            .            .

Hi! Interesting question... I've built a couple of the pulsers, but I never looked at the waveform of the pulser on the scope. I listened to it on the speaker, and used it to drive various CV inputs of oscillators and filters and what not to make whoop-whoop sounds. I was frankly so thrilled that it was working I didn't dig in much more.

If I had a working scope I'd check it out and let you know, but right now (a) I broke the ground pin on my scope probe, and (b) my scope is kind of freaking out and claims a 120 volt 60 Hz sinusoid is superimposed over anything I'm trying to measure. Fortunately this signal that looks mysteriously like mains current isn't actually showing up on the scope proble - but it does appear my scope is kind of buggered. :(

- Aaron