pseudo-random shift generator

[jean-charles maillet]

>The circuit in question ( ETI 4600 page 20 )

I don't think I've ever seen that publication anywhere ... actually I'm
more interested in the chips used (their #'s) and the kind of gate used to
"stir" the sequence and as well pin-connections ... someone once verbally
described these circuits to me and so I've got an idea of what's going on
here ... maybe someone could provide me a textual description that gives
enough info so I can experiment on this ... I've heard that registers of
prime order (3,5,7,11,13 ...) are best to use with this technique ...

btw, I was thinking of using a shift register whose internal bits have
individual pin-outs to ease manipulation of signals and in-circuit testing
and variations ... even without this I suspect that two plain shift
registers (with only one in and out) can have their outputs combined and
nored/exored/whatever to be used as a new input for one side of the signal
chain (this is what I mean by cross-coupled) ... I can very well understand
how the authors of the circuit you mention would provide a serial expansion
to the classic shifter/generator circuit but that to me is the lazy
"engineering" approach ... a parallel expansion should be much more
economical and generate much more complexe sequences then the serially
enhanced circuits ... perhaps cross coupling two shift circuits that have
differing lengths is the way to go ... in which case a register with
available outputs on each bit would make sequences easily switcheable ...
just a hunch ...

jc

/////////////////////////////   vivaAnalog    \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\

/////////////////////   http://www.lynx.bc.ca/~jc/    \\\\\\\\\\\\\\\\\\\\\\

     Vacuum tube modeling - Great guitar players - Traynor amp schematics

//////////////////////////////////    \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\