Serge Waveshaper schemos on Music Machines

tomg tomg at
Fri Jul 17 20:58:01 CEST 1998

On 16-Jul-98, Jim Johnson wrote:

>4) Why use an LM3900 in this circuit, rather than a TL-074? 

I used 39OOs to replicate the Serge Boolean Logic Module. This may or may not
be how Serge does it I don't know I've never used a Serge. It works anyway.
Check it out.

Maxx Boolean Logic BLG-1A

The LM39OO "Norton" amplifier uses a inverted current mirror to achieve a
non-inverted input instead of the normal differential input op-amp. This
design allows the amplifiers to be run from a wide range (+4-36V) single
supply solving most of the problems usually encountered running op-amps from a
single supply. The amplifiers of the 39OO can be overdriven and used in low
speed digital applications at more than +5V to supply more current than
standard digital gates. Two inverters ,AND ,OR and XOR gates built around
LM39OOs. May be combined to form NAND, NOR ect...


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