Re: Puredata PDC 400E faxmodem power supply?

["Paul Grammens" <grammens@svn.net>]

Brian K. Lambert <bl3@ra.msstate.edu> wrote in message
398F108E.74A97DE6@ra.msstate.edu">news:398F108E.74A97DE6@ra.msstate.edu...
> Hi,
>
> I picked up a Puredata PDC 400E external fax modem today, and want to
> verify the power supply I have is correct:
>
> The power supply has an output of 16 VAC.  The connector fits, but I'd
> like to verify before I plug it in!  My web searching has been less than
> fruitful.
>

That kind of info is just about impossible to find. Try reading the fine
print on the underside of the modem, and see if the power connector on the
modem is labeled. What I usually do if there is no external info is open the
modem and study the circuitry to see if it takes AC or DC. AC requires
diodes and filter capacitors to change the AC to DC, then usually feeds that
to a voltage regulator.  DC usually just has a filter capacitor and
regulator. You also may get lucky, and the circuit board may be labeled at
the power connector "16VAC".
Once you know whether it takes AC or DC, just try a 9 Volt adapter, AC or DC
as required. That's the most common. If it works, that's it. If it comes on,
but malfunctions, try a higher value. 12,  14, 18 V are pretty common.
If it works, but the case gets really hot, you could try a lower voltage.
Hope that helps.
-Paul