Maker Pro
Maker Pro

Generating 48V@50mA from 5V for microphone phantom power...


Allan Herriman

Jan 1, 1970
It's possibly a bad idea to use 1/2W resistors, as these aren't
usually available in the close tolerances required. The match (but
not the actual value) of the two resistances needs to be very

It is possible to make up the desired power rating by using a number
of lower powered precision resistors in parallel or series.

.... if anyone knows of a source of matched 6.8kohm 1/2W resistors,
please let us know.