[sdiy] single supply expo?

[Dan Snazelle]

I am trying to find or figure out how to make, a Single supply NPN pair expo converter

I am trying to make something that can run off of a 9v battery


all the expos I know of connect somehwhere to -v.

i was wondering if I could make an expo that never connected to -v OR just had a +/VB/and grnd setup for dual supply


this does NOT need to be super precise (its not for a vco)

thanks for any help!!