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

[Dave Leith]

It's C110 on this schematic

http://users.ece.gatech.edu/~lanterma/buchla/boards/mea_pulser/mea_pulser_schem.png

On Sun, Jan 16, 2011 at 10:39 AM, Dave Leith <dave.leith at gmail.com> wrote:
> Thanks for the reply Aaron
>
> I've studied the schematic and it "seems" that this odd behavior is
> normal but I'm not totally sure. And if it is correct of course I'm
> curious why....
>
> Here's a bit from an older question of mine
>
> Not sure if this is normal but it seems to be created by the capacitor (910pf to
> ground) that is in the reset circuit and stretches the length of the
> reset pulse. The cap is on the front panel. If the cap is removed one
> gets a perfect downward ramp at all frequencies. The reset circuit is
> connected between pulser pls in <3> and pulser pls out <2>
>
>
> On Sun, Jan 16, 2011 at 10:29 AM,  <lanterma at ece.gatech.edu> wrote:
>> 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
>>
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>