With regard to an electronic "ticker", my "Senior Project" at Cal Poly was just that sort of device.
I tried various sound sources: a damped high-frequency sinusoid, a pulse, finally settling on two cycles of an 8kHz squarewave. More than a single pulse, the 8kHz imparted a high-frequency timbre to the sound and gave me time to deliver more energy
to the speaker. Three "tweeters" were tried as speakers: a horn, a dome and a cone tweeter. The cone tweeter had the most narrow dispursion; it was the best for
"exploring space", while the dome eluminated (as you might say) more of the area.
The horn was afflicted with resonances that imparted low-frequency sound to the ticks.
It was fun to use, socially offensive to some, and worked pretty well. As a training aid for use of echo location, its vurtues were praised by Larry Scadden.
Should I revive that relic?
Bill Gerrey
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