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Old October 11th 14, 04:00 PM posted to rec.radio.amateur.homebrew
Michael Black[_2_] Michael Black[_2_] is offline
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First recorded activity by RadioBanter: Mar 2008
Posts: 618
Default Frequency accuracy in older RXs

On Sat, 11 Oct 2014, Ralph Mowery wrote:


"gareth" wrote in message
...
Oops! Got the two swapped round!

Square = odds, Triangle = evens, Sawtooth = raucous!

Still sort of wrong.

Square and trigangle are both odd harmonics.

Square wave harmonics are reduced by 1/N and triangle waves are sort of 1
over the square of the harmonic.

I forget the reasons for triangle waveforms in electronic music, or
testing, but one thing is, it's easy to generate, and with diodes, you can
turn it into a reasonable sinewave. There was the Intersil 8038 function
generator IC (Exar had similar products) that put out square, triangle and
sinewaves. The sinewaves were synthesized with diodes from the triangle.
The squarewave was a byproduct of generating the triangle. And there was
an adjustment so you could turn the trianble into a sawtooth, which has
its own uses.

Michael