Are there any DIY kits to build a battery run portable Phantom Power supply?

[canidoit]

I am trying to find an affordable way of running my AT416 shotgun mic that requires 48 volt phantom power.

Is this difficult to build where phantom power is provided using maybe 2 X AA batteries or 9 volt battery like in portable recorders like the Zoom H4N??

 

[RuudNL]

http://www.vansteenissoftware.nl/48V_box_r1.pdf

 

[JohnRoberts]

One issue from using a switcher to step up battery voltage is that even with perfect conversion efficiency the current draw gets multiplied proportionately. So whatever mic current draw , will get multiplied between 5x and 6x from the 9V battery, even more from 1.5v cells.  9V cells are a couple hundred mA hours so do your own math for life expectancy. THe AA cells have more mAhrs, but less V so it pretty much cancels out. With batteries it's pretty much like capacitors so size or volume determines current output across similar battery technology. A switcher will have some overhead loss related to switching device on resistance, so higher battery voltage  will run at lower current "and" be less affected by the switch forward voltage loss. 

Note: some phantom powered mics will operate Ok with less than 48V. As I recall Peavey used to sell an accessory phantom supply that provided only 9V. many install products use +15v phantom. While I do not expect 9V to be enough for "all" mics. 

If you have a specific mic in mind, and apparently you do, perhaps consider some bench testing with a variable PS to determine how much voltage you really need. If you can get away with stacking two or three 9V cells, you will get pretty good life, with a lot less complexity.  If you really need the full 48V use a switcher.

Back in the bad old days when they still made portable tube radios, I recall seeing 24V (?) or so batteries. These days high voltage batteries are not as common.

 

[RuudNL]

Maybe two of these:
(The right one of course...)

 

[ricardo]

If you are not strapped for space or weight,

• 5 x 9V PP3s
• 5 x PP3 connectors
• 2 x 6k8 1% resistors
• 100u/50V Aluminium Electrolytic across the 5 batteries in series

work well.  Just check the batteries are fresh before an important recording session.  Many modern mikes will operate nicely down to 12V but don't risk it.

Strap all 5 together with an elastic band.

Build your own fancy box around this.

 

[gyraf]

+1 for 5 x 9V batteries. This is as simple and practical as it can be done, not considering weight&size.

Jakob E.

 

[JohnRoberts]

Yes, I just repeat you may not need all five 9v batteries. I have seen mics that pad the voltage down inside to more like 10V or less. The typical mic level output signal swing is "mic" level so volts or less.

If this rig is for one known mic you can figure this out empirically. For a universal solution spring for all five batteries...


JR