David can you explain how the tuning would work without the technical stuff? I think installing it right next to that ugly Kenton switch would be a good place for it. And can we add spinning fans right under the vents? J/K about the last part. hahha -Scott ________________________________ > To: yamahacs80@yahoogroups.com > From: r_j_d_2.phila@... > Date: Mon, 15 Sep 2008 17:23:10 -0700 > Subject: Re: [yamahacs80] Auto-tuner / tuner assist idea > > > thanks for putting the thought into this, david. im in the same boat as scott; i dont understand the nuts and bolts, but i could be interested in this as a functional device for tuning. as far as panel mounting, i wouldnt be willing to mod the front panel of mine, though, so i would have to find another place to put it. > > --- On Mon, 9/15/08, David Rogoff wrote: > From: David Rogoff > Subject: [yamahacs80] Auto-tuner / tuner assist idea > To: yamahacs80@yahoogroups.com > Date: Monday, September 15, 2008, 7:44 PM > > Hi all. > > Well, we had out CS80 BBQ yesterday. It was a good time with lots of > > noise :^). More on that later. > > Toward the end of the afternoon, we were talking (actually, Scott M. > > was requesting/begging) about some kind of auto-tuner for the beast. I > > thought about a few ways to do it, but then I realized I have a few > > others things to do in the next couple of years, so I dropped the > > plan. However, I have thought of a pretty simple board that could be > > mounted in the CS80 to really speed up the manual tuning procedure and > > not require any external tuner or test equipment. > > I've put a scan of my first sketch here: http://launch. ph.groups. yahoo.com/ group/yamahacs80 /photos/browse/ 68f7? > > c= > > Quick explanation: I grab the 8 trigger/gate signals and convert them > > to binary with a 4532 (this whole thing uses the same 4000-series CMOS > > chips that are already used all over the CS80). One place this goes is > > a 4511, which drives a 7-segment LED display, showing you a number > > from 0 through 7 for which pair of board is triggered. If you hit more > > than one key at a time, all bets are off! > > The binary code also controls the 4051 8-to-1 muxes in the upper > > right, which are wired with the pulse outputs from each voice card. > > Therefore, you automatically select the correct oscillators. (I just > > realized, since only one key is allowed to be hit at a time, the muxes > > can just be OR gates). These go through a couple of 4013 flip-flops > > which turn them into nice, clean square waves at octave down. > > Next, at the bottom of the page, we've got a crystal tuning reference > > (could include a jack for an external reference??) . This is divided > > down to all the required octave for tuning. Another pair of 4051s pick > > the correct octave automatically based on the Feet switches. > > Finally, in the circuit above this, the oscillator outputs are X-ORed > > (digital ring-mod - easy to hear/see beat frequency) with the > > reference tone. These drive red/green LEDs that show the beat > > frequency. Also, a pair of switches allow sending the oscillator, > > reference tone, or X-OR tone from either channel to an audio output. > > This lets you hear the tones, which can help with tuning, especially > > if the oscillators are way off. > > Comments? Criticisms? Suggestions? Would this be something people > > would want to install in their keyboards? It would probably mount > > inside the front panel, near the Feet switches. > > More later, > > David > > > > > > > > > > > > [Non-text portions of this message have been removed] > > >
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RE: [yamahacs80] Auto-tuner / tuner assist idea
2008-09-16 by Scott Metzger
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