David Duffy (AVD <david <at> audiovisualdevices.com.au> writes:

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> I'd like to make a programmable (serial control) oscillator as part of a=
=20
> test rig.
>=20
> All I need is square wave output (adjustable symmetry would be nice but=20
> not essential) and a frequency range of 0.1Hz to 20Khz or so. The area=20
> of interest right right now is more like 0Hz to 200Hz for simulating a=20
> pulse counting input to the device under test.
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> I'm using a $100 function generator for now, but the display resolution=20
> of 1Hz is somewhat limiting.  PC control would also enable me to=20
> automate some of the testing.
> David...
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DDS generator will fit the bill.  There is an article in recent NutsnVolts
magazine that uses PIC to control PLL to do just that, it's trivial to add
serial interface to that.  IIRC, total cost was under $70. =20

Sergey Dryga
http://beaglerobotics.com




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