[HAM] what sort of Hammond chorus generators were there?

[John Freund]

> Just curious: The BC chorus generator generates the chorus effect by
> having tonewheels that are all made as dual tonewheels, that way
> generating
> a beating.

BC and D models (same guts as BC in a C-style cabinaet - NOT a D-100) and
the E-concert model had chorus generators.  This was a completely separate
generator that duplicated and detuned the UPPER harmonics to create the
chorus effect.

> What exactly did the chorus drawbar do on a BC?

The chorus drawbar closed a gang-switch that sat on top of the chorus
generator, closing contacts that connected the chorused tones to the
corresponding keying circuits.

It was the addition of this second generator that required Hammond to ditch
the original A-size cabinet and move to the more spacious B-size.  

> Then there were D-100s, that had two tone gennies. How was tha chorus
> generated on them?

D-100's are like sort of a combination of and RT-3 and an A100.  But the
built-in speaker systems are a helluva lot beefier than the A100.  They all
(of course) have scanner vibrato. D-100's were built from '63-'69.

/John