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Saxophone Switching Logic

Mike Lansing

Oct 7, 2017
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Around 1986, the time of building a saxophone switch-logic circuit using Radio Shack logic gates, MIDI (musical instrument digital interface) had already produced controllers on the market for guitars, etc. but left woodwind players behind. The circuit was connected to switches under the saxophone keys, and the MIDI interface itself was simply opto-isolators placed under the keys of a Prophet 600 synthesizer. The system not only allowed a woodwind player to operate the synth keys as if they were a piano player, it indeed provided chord-making capabilities that no woodwind player ever had.

While having been out of electronics for decades, there is a question as to refreshing one's remembrance with such classics as the now apparently out-of-print "Getting Started in Electronics" by Forest Mims. Was that book not once available on the internet?

Another question is related to tone detection, and we notice from the search that there are a few threads on the topic. Is there a circuit that would filter out all other incoming frequencies except 238 Hz?

Regards,
Mike Lansing, USA
 

73's de Edd

Aug 21, 2015
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Sir Mike Lansing . . . . .

Well first off lets enhance your research learning curve.
INITIAL main point of interest is IF the unit is being available as a PDF . . . so o o o o o o
PDF and then plus + . . . . . for additionally related info . . . . within a specific closed range of interest by " ".
Combinationally you then get . . . . .
pdf + "getting started in electronics"
Then you go to the 'ole interweb and knock on Mr "GOGGLE's" portal, and then request of him . . . .

pdf + "getting started in electronics"

And then, within just a mere 1.22228 7 / 69ths milli seconds of transit time . . . .BAMMMMMMMMM . . . you then have yourself . . .
Sir Forrests laboriously composed m u l t i page legal pad creation of . . . .

https://docs.google.com/file/d/0B5jcnBPSPWQyaTU1OW5NbVJQNW8/edit


Fully digest that content and then it would be time to figure the frequency spread between side by side desired sax notes/ frequencies and determine the need of mere phase shift, twin T filters or even more dedicated and sharply differentiating LM565 IC's.

73's de Edd
 
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Mike Lansing

Oct 7, 2017
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Thanks much, 73's de Edd. Barnes and Noble told me it was out of print and did not try to go further to help me find it. No longer playing saxophone, though one musician is working on frequencies against bark beetles. Thus my interest is to place a microcassette recorder into a Ponderosa via a cheap wal-mart drone that has a 238 Hz sound recorded on it. This is the frequency of one species' chirp. Pressing on, an audio circuit that could also detect 238 Hz could operate an apparatus of capture. The problem would be to detect the location of the chirp to direct the capturing apparatus.
 

Mike Lansing

Oct 7, 2017
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An awesome blast of nostalgia, 73's de Edd. Yes, Mims shows the drawing of the deadly solenoid that could, if one desired, operate the coup de grace dart!
 

Mike Lansing

Oct 7, 2017
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Problematic may be the length of time of the bark beetle chirp. According to www. "Tone Detector Circuit" (www.scary-terry.com/more_stuff/tonedet.htm) which mentions the LM 567...."I found that for reliability, the length of the recorded tone had to be at least 0.5 seconds long.'

Problematics:

1.) superimposed chirps, ambient noise, etc.

2.) no oscilloscope image with which to analyze the chirp

3.) enough sampling to understand the range of variations of the chirp, which is species-specific

This technology could be developed to tentatively identify many different species, not simply bark beetle species.
 

Mike Lansing

Oct 7, 2017
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The chirp of bark beetles is produced by stridulation, and the mechanical forces of such stridulation that cause for instance, 238Hz, is quite comparable to mesh-current equations. One can see this relationship by superimposing an image of the insect's stationary mechanism on its body over the circuit problem in Figure 3.29 of Fundamentals of Electric Circuits, McGraw-Hill Education (Asia), International Edition [2013]), whose Solution states: "We have five meshes, so the resistance matrix is 5 x 5. The diagonal terms in ohms....'

The diagonal term in ohms, then, is precisely the resistance conveyed by the stationary apparatus that will be swept by the moving arm or leg of the insect that produces the frequency.
 

Mike Lansing

Oct 7, 2017
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The stridulation that produces frequencies of the insect chirp are an example of the becoming-space of time and the becoming-time of space. Curiously, the International Edition we have quoted from states on the back cover: "This book cannot be re-exported from the country to which it is sold by McGraw-Hill. The International Edition is not available in North America."
 
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