Octave down schematic.

Started by fuzzo, June 08, 2009, 01:27:33 PM

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Scruffie

Quote from: fuzzo on September 28, 2010, 12:53:32 PM
Sorry to cut this intersting talking but , no one , made a PCB for the OC2 chopped ? (make it on veroboard would require a lot of bravery :icon_lol:)
I think Taylor has something Planned in that department for a run of PCBs.

sponboy

Hi guys,
Im fairly new to this octave stuff but have made other pcbs in the past.

I cant find any pcb layouts for this pedal anywhere on the net and Im fairly useless at reading schematics, anyone know where to find one/have pcbs (or just the layout) for sale?

Cheers,
Kris.

El Heisenberg

"Your meth is good, Jesse. As good as mine."

Paul_5

Quote from: fuzzo on September 28, 2010, 12:53:32 PM
Sorry to cut this intersting talking but , no one , made a PCB for the OC2 chopped ? (make it on veroboard would require a lot of bravery :icon_lol:)

I built mine on overboard. I'd say it was more stupidity/naivety than bravery. I considered designing a board for an OC2 clone, but to be honest, couldn't be bothered.

It was about my 10th build or something and I approached it with childlike confidence, as nobody had told me it should be difficult. I had a dicky switch and a dry joint on one of the pots, so fortunately I didn't have to probe the board to trace faults on there.

SirPrimalform

Quote from: merlinb on September 27, 2010, 09:34:18 AM

Incidentally I discovered all this by trying to design a simplified octave down. Eventually I realised that it was impossible to do without two comparators, so my final circuit eneded up extremely similar to the Boss, much to my chagrin  :icon_lol:
(Actually my circuit has slightly better tracking than the Boss since one of my comparators detects the zero crossing rather than the peak, but hey... ;)

I hope people forgive the necro (but it seems like the real necro happened back in November anyway). I'm really interested in this. If one of them detects peaks and the other detects zero crossings then does that mean the flipflop output is roughly 25% (or 75%) duty cycle? And what is the advantage of having one of them detect zero crossings? I've been reading this thread mainly for the stuff about the fundamental extractor because I was looking for some way to get a clean square signal to use with a PLL to make a (probably glitchy) synth octave up effect.

merlinb

#45
QuoteIf one of them detects peaks and the other detects zero crossings then does that mean the flipflop output is roughly 25% (or 75%) duty cycle?
From the first flip flop, yes. After being divided by the second flip flop it will be 50% (inasmuch as duty cycle has any meaning when it is tracking a constantly varying signal)

Quote from: SirPrimalform on March 31, 2015, 09:40:51 AM
And what is the advantage of having one of them detect zero crossings?
Zero crossing are easier to detect than peaks. Peaks are always changing in height. Zero crossings are always..well, zero.
http://www.diystompboxes.com/smfforum/index.php?topic=76997.msg732912#msg732912
http://www.diystompboxes.com/smfforum/index.php?topic=76997.msg733108#msg733108

SirPrimalform

Quote from: merlinb on March 31, 2015, 02:53:50 PM
QuoteIf one of them detects peaks and the other detects zero crossings then does that mean the flipflop output is roughly 25% (or 75%) duty cycle?
From the first flip flop, yes. After being divided by the second flip flop it will be 50% (inasmuch as duty cycle has any meaning when it is tracking a constantly varying signal)

Quote from: SirPrimalform on March 31, 2015, 09:40:51 AM
And what is the advantage of having one of them detect zero crossings?
Zero crossing are easier to detect than peaks. Peaks are always changing in height. Zero crossings are always..well, zero.
http://www.diystompboxes.com/smfforum/index.php?topic=76997.msg732912#msg732912
http://www.diystompboxes.com/smfforum/index.php?topic=76997.msg733108#msg733108

Well yes, I suppose that last one was a bit of a silly question. I guess I should have asked why Boss went to the trouble of detecting the peaks if zero crossings do as good a job (or better even)?

merlinb

Quote from: SirPrimalform on March 31, 2015, 08:52:34 PM
I guess I should have asked why Boss went to the trouble of detecting the peaks if zero crossings do as good a job (or better even)?
Maybe they copied it from bits of an older circuit. Maybe they tried it but found it didn't work as well in their particular incarnation. Maybe they just didn't think of it (the world of FX pedals doesn't attract the cream of the engineering crop  :icon_lol:). Who knows.