Dario Greggio wrote:
> am posting this again to just get more suggestion (I already got one
> from Harold :)
>
> I'm about to design the device, starting from a filtered PWM output of a
> PIC24. I basically have to put down a power-supply-stage and an output
> stage.
>
>
>
> Anyone has familiarity with this:
> http://cyberdyne.homeip.net/public/FM-AirDryer.pdf
> ?
>
> I have to implement such a protocol on a board, basically to make it
> behave as a peripheral of such.
>
> Nothing really hard - 1000-2000Hz sine wave, 2sec steps, 1.5 duration ...
> I just have some doubts on what it really means the usual "0dB / 600ohm"
> :) I never got it through in depth. I will pick an amplifier suitable to
> that.
>
> And... I also can't understand exactly what "synchronizes" the units. I
> suppose a large pause. But will see :)
>
>
>   
Oh. long ago. I think 0dB into 600 Ohms from 600 Ohms source is 775mV on 
the line. (1mW in load maybe)
so if you have opamp or low Z source, you have 1.55 V driving 600Ohm 
resistor. Normally it's balanced so non-inverted and inverted both 
driving 300 Ohms in series with output connector. Load is then also 600Ohms

This is because 600 Ohms was balanced transmission line for Audio.


-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist