I have been asked to mod a Fairchild F/22 Microphone ( AKA Syncron AU7A), it is the first commercially available condencer mic circa 63-64',the issues with this unit are that although It is been compared to a Neumann U87 in frequencie responce and in tone ( some what ) its a historical piece of recording equipment, produced before phantom power was available ,and depended on 2X 303448 mercury batteries ( unavailable ), for 42 volts DC, and 2X Mallory TR133 bateries for a separate 8.7 -9 volts DC .
I have been asked to mod this to accept a 48 volt Phantom and split the 48 volts to separate 8-9 volts from that, one of the main concerns is the fact that the mic has a screw lock 7 pin amphenol connector and locating the mate for it to could be challenging. then to build an XLR to 7 pin amphenol breakout cable .
I found a circuit diagram for this but am leary as it utilizes a 110K trimmer to dummy down the voltages instead of a 7809 regulater
I have the pin layout for the amphenol connector to build the adapter cable as well
this is the actual breakout cable for this unit
does any one have expirience with this connector or know what it is called ? , I went blind looking for one earlier today starring at every thing in supplier on line catalogs .
I'm still deciding if i will accept this job or not , i dislike doing other peoples mods , they are never satisfied with the results and i dont want to reinvent the wheel .