greenmeanh1 1/20/2018 3:46 AM
Sennhieser MKH 815 T Power supply.
Ok i got these mics some time ago from a couple different sources. I have five of them in total to include Two MKH815T complete Three MKH415T in various states of disarray. Basic same mic with different length tube. I would like to use them at least the two 815's but they use a unique power supply (T power). I have seen some cheap converters out there but they are not right for the 415, others have battery power. Ideally i would like something that takes 48v phantom and steps it down to the 12v needed to power the mic. The sennhieser MZA56p power supply for this cannot be found anywhere and likely highly coveted by movie guys. I have the schematic for the mic but not the power supply. Any would be schematics floating around that one might be able to build such a device or similar??
 
Jazz P Bass 1/20/2018 5:44 PM
Not too sure what a T power is but could this be what you need? [url]https://www.bhphotovideo.com/c/product/147515-REG/Sennheiser_12T_P48_12TP48_48V_Phantom.html[/url]
 
g1 1/21/2018 2:36 PM
The schematic for that supply does not seem to show up, but Neumann seems pretty helpful if it's for a U77 ;) At least they used to be: [url=http://www.neumann.com/forums/view.php?bn=neumann_archive&key=956515247&v=f]Archive - U77 T-Power Supply[/url]
 
greenmeanh1 1/22/2018 3:45 AM
Not much info. But i did find this. [url]http://recordinghacks.com/pdf/sennheiser/MKH-415t.pdf[/url]
 
greenmeanh1 1/30/2018 2:30 PM
So this is the schematic i am going to build from using the second schematic listed. [ATTACH]46867[/ATTACH]
 
nevetslab 2/13/2018 11:36 AM
I recently revived three Sennheiser MKH404 RF mics. This was their first RF mic series, and was prior to their clever means of the T-Power. I believe the JKH415T is also using this circuit, and won't work on T-Power. I ended up building a simple Power supply from on-hand parts, ending up with -9.6VDC to run the mics. I've attached the schematic for this MKH404, and likely to be the same for your MKH415's. Also attached the power supply I built. Photos below: [ATTACH=CONFIG]47077[/ATTACH] [ATTACH=CONFIG]47078[/ATTACH] [ATTACH=CONFIG]47079[/ATTACH] [ATTACH=CONFIG]47080[/ATTACH] [ATTACH=CONFIG]47081[/ATTACH] [ATTACH=CONFIG]47082[/ATTACH] These mics came wth In-line Output transformers, as seen in the last photo above. The small Toroidal power transformer was too high to directly drive the 7912T IC -12V regulator, so I added a pass Xstr ahead of it. As the aged wet-slug Tantalum caps inside the mic all had 10V ratings, I placed a RED LED and a 100 ohm series resistor to the mic from the power supply, which dropped the voltage down to -9.6V, and gave a useful RED LED power-on indiactor when the mic was plugged in. Power supply for what I built follows, along with a BBC report I came across that shows the MKH404 schematic [ATTACH]47083[/ATTACH] [ATTACH]47084[/ATTACH] OH....I just found I had the 415Service manual, which I've included [ATTACH]47085[/ATTACH]
 
greenmeanh1 2/13/2018 5:39 PM
Outstanding information!! Thank you very much!! Nice run of tests for calibrating the mics also including the schematics for the test gear. Amazing!!