Modification SD49425XB-HNR 4MP, Add 12 Volt Microphone Power Output

[guykuo]

Microphone power output mod for a SD49425XB-HNR (running on POE+ power) to provide 12 volt microphone power.

Much as I did for the SD49225T-HN, in Modification - SD49225T-HN Add External Microphone Power The resultant power out the DC input jack of about 25 ma powers a Microseven M7WP-MIC.
The process is similar but the SD49425XB-HNR's POE power board is differently configured. So, the connection points differ.

I won't repeat the generic camera opening and board removal details of the other thread, but here are this new POE power board's connection points to do the microphone power output mod.

I tap the POE power supply's 12+ volt power via a current limiting resistor and feed power backwards out the external DC power jack. The power is filtered with a 100 uFd capacitor.

Here is the POE power supply board top view. It is definitely different from the one in other thread, but shares same pinouts on its connectors (at least regarding power). I suspect one can move the POE supply board from one camera to another, but have not test that.

 

[guykuo]

The +12 volt power is still available on pin 8 of J2

 

[guykuo]

We tap that power with a 480 ohm resistor to limit current draw. The other end of the resistor feeds power out what is normally the 12 volt DC input. Filtering is performed with a 100 uFd capacitor.

 

[guykuo]

Here is the completed wiring to implement what I drew in the schematic overlay. Resistor and capacitor were positioned to fit avoid the very crowed space between board center and camera wire feed.
Be sure to observe polarity of your electrolytic capacitor.

 

[guykuo]

Double check that your resistor, capacitor and wiring are not shorted and fit the space available.