The Green Hornet

Built for Raphael Tschernuth

The Green Hornet came out of a challenge.  Raphael wanted a pair of tube microphone preamps and I told him if he wanted to keep costs down he should find a suitable case.  Being the flea market hound par excellence that he is, Mr. Tschernuth came up with an old DDR-era tube oscilloscope which suited the bill perfectly. 
The preamps have 48V phantom power (with green led signal lamps of course!), phase and pad switches.  The gain is activated with a 12 stage shunt attenuator switch in 3dB steps.  The low impedance inputs are balanced with OEP transformers while the high impedance inputs accept line or instrument levels.