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Phil Allison[_3_] Phil Allison[_3_] is offline
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Default phase shift audio oscillator 5Hz to 100kHz++


"patrick-turner"

Phil mentioned the drive mech for the variable tuning cap in the wien bridge
oscilator he has....

The shaft is driven by a backlash free, 60:1 worm reduction drive and a
200 point scale.

Verrry silky.


** Ambiguity fix.

The 200 point scale is engraved on a 4.4 inch dia steel disk that rotates
with the worm drive, making 6000 setting points per range. 30 turns x 200 =
6000.

Well Phil, your dial certainly seems nice by what you say, but how accurate
are the 6,000 points on the dial? It would seem that the dial length around
the 4.4 inches is roughly 13.8 inches long, 351mm, so distance between each
"point" is 351 / 6,000 = 0.058mm and too small to be useful.

** ROTFLMAO !!!!!!!!!!!!!!

351 / 200 = 1.755mm

There a 30 turns of the dial for 180 degrees on the gang.



.... Phil