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Products => Test Equipment => Topic started by: Homer J Simpson on April 22, 2014, 03:07:13 am

Title: What is this and what does it do?
Post by: Homer J Simpson on April 22, 2014, 03:07:13 am

I have no clue on this.

Comdyna Variable Diode Function Generator

http://www.ebay.com/itm/Comdyna-Variable-Diode-Function-Generator-Model-701-/231210733836?&_trksid=p2056016.m2518.l4276 (http://www.ebay.com/itm/Comdyna-Variable-Diode-Function-Generator-Model-701-/231210733836?&_trksid=p2056016.m2518.l4276)
Title: Re: What is this and what does it do?
Post by: miguelvp on April 22, 2014, 03:25:45 am
No idea either but:

http://www.analogmuseum.org/library/comdyna_functiongenerators.pdf (http://www.analogmuseum.org/library/comdyna_functiongenerators.pdf)
from:
http://www.diale.org/dfg.html (http://www.diale.org/dfg.html)
manufacturer:
http://www.comdyna.com/ (http://www.comdyna.com/)

Some kind of analog module, so it means you need an analog computer of shorts. Edit: maybe not on that module.

Some info about how they run: Edit nope this is for the analog computer.
http://seit.unsw.adfa.edu.au/staff/sites/petersen/Teaching/Control_Theory_1/Lab2/lab2.pdf (http://seit.unsw.adfa.edu.au/staff/sites/petersen/Teaching/Control_Theory_1/Lab2/lab2.pdf)

Edit: more info:
http://www.analogmuseum.org/english/library.html (http://www.analogmuseum.org/english/library.html)
Title: Re: What is this and what does it do?
Post by: FrankenPC on April 22, 2014, 04:11:39 am
Fascinating!  I'm halfway considering buying it just to tear it apart.
Title: Re: What is this and what does it do?
Post by: Alexei.Polkhanov on April 22, 2014, 05:21:29 am
Well simple search for "diode function generator" returns plenty of stuff to read  :)

Device could have bunch of diodes connected in series with variable resistors in parallel making it possible to shape triangular wave or ramp on input to an arbitrary output waveform (within limits).
This device may actually have series of "Ideal diodes" instead of real discrete diodes. Here is interesting link: http://schmitzbits.de/diode_tutorial/index.html (http://schmitzbits.de/diode_tutorial/index.html)

I think I have read about the idea in "Art of electronics".

Also isn't this how Electronic music was made in 60s and 70s?