Phantom power

ditbestand

New member
hello
is was wondering if it was possible to buils a phantom power unit for an mic because i don`t have enough money to buy one
 

billisa

New member
ditbestand said:
hello
is was wondering if it was possible to buils a phantom power unit for an mic because i don`t have enough money to buy one

i may be speaking out of turn here, but given what basic phantom power units can be had for, i wonder if you'd in fact wind up saving money. assuming you have the skill, you might want to build one using the best components to ensure a high level of quality (plus the satisfaction of having done it yourself), but i wonder if any real money would be saved doing it on a tight budget for an entry level unit... plus the fact that with a device intended to send 48volts into a mic, you'd want to make sure it was made properly. still, there are probably schematics out there with parts lists for you to find.
 

crazydoc

Master Baiter
This is about as cheap as it's going to get:

Harvey Gerst said:
I think I can explain it pretty simply. You'll need:

a small box,
a female and male XLR,
5 - nine volt batteries,
5 - nine volt battery clips,
two - 6,800 ohm (1%) resistors,
and two small, non-polarized 10 mfd capacitors.

Wire all 5 of the nine volt batteries in series, the (-) of one battery connected to the (+) of the next battery.

Connect the (-) pole of the last battery to Pin 1 of both XLR plugs.

Connect the (+) pole of the first battery to one end of both 6,800 ohm resistors. Tie the other end of the resistors to Pins 2 and 3 of the female XLR (the XLR that goes to the mic).

Connect one of the 10 mfd capacitors from Pin 2 of the female XLR plug (the XLR that goes to the mic) to Pin 2 of the male XLR plug (the XLR that goes to the board).


Finally, connect the other 10 mfd capacitor from Pin 3 of the female XLR plug (the XLR that goes to the mic) to Pin 3 of the male XLR plug (the XLR that goes to the board).The two capacitors prevent the phantom voltage from getting back into the board.

Mount the whole thing in the box, and you're ready to go. You can add a two pole (off/on switch in series with the batteries, if you wanna get fancy and have a shutoff. You can even put an LED in it to indicate "On").

Current drain is minimal, so the damn thing should last forever (even if you leave it on constantly).

If you pick up any stray hum from the box, line it with aluminum foil and connect the foil to Pin 1 of either XLR.
 

crazydoc

Master Baiter
Oh, and for the battery clips you can take apart dead 9v batteries and use the contacts from them as battery clips. They already have wires attached to them.
 

ditbestand

New member
thanks a lot for that explanation
one last quistion is it possible to use the power of those 5 batteries for about 4 connections because else you will need 20 batteries for fantom power for 4 condenser mics
 
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