Hi Dave--
No transformer I can see.
http://www.uwm.edu/PSOA///Film/Danielson/Mic%20Preamps/AudioBuddy_PCBoard.j=
pg
Hope you see something interesting, Best, Rob D.
=3D =3D =3D
At 2:56 AM +0000 8/26/04, Dave J wrote:
>If the input measures as a low resistance then
>there is probably an internal 50/60 Hz transformer
>which would imply DC should not be applied. If you
>know for a fact that there is no internal transformer
>then it should be possible to run the unit on 12VDC
>unless something really tricky is being done.
>
>Before applying voltage try e-mailing M-Audio;
>"support at m-audio dot de"
>
>
>I would be willing to look at a unit but a few decent
>photos of the insides of one would probably give us
>the answer.
>
>Dave
>
>--- Rob Danielson <> wrote:
>> Something ingeniously simple like this is what we
>> need. I just tried 10 volts into my Audio Buddy
>> and the main power LED doesn't light. I recall
>> discussion about Len Moskowitz's involved M-Audio
>> Duo modification for portable DC which also has
>> the 10 VAC input. The phantom power LED will
>> light with a 10 VDC input; this might be a clue
>> as to getting more power to this part of the
>> circuit. We were attaching the 4- 9volt batteries
>> for +18 and -18 before the regulators. The
>> phantom voltage provided was low, ~40 volts. The
>> A-B spec sheets shows the 10VAC at 300ma; the 9
>> volt batteries don't seem seem have have enough
>> current. If someone on this list familiar with
>> this kind of circuitry has the interest and time
>> to work out a portable power solution, I'll send
>> them my Audio Buddy to study and modify. Best,
>> Rob D.
>>
>
>
>
>
>
>"Microphones are not ears,
>Loudspeakers are not birds,
>A listening room is not nature."
>Klas Strandberg
>Yahoo! Groups Links
>
>
>
>
--
Rob Danielson
Film Department
University of Wisconsin-Milwaukee
________________________________________________________________________
________________________________________________________________________
|