Square wave ingition triggers

[Thomas Matthews]

Not sure, but it looked like a standard late 70's pickup for a Ford
V8. matter of fact, a guy I knew told me he used one after cutting
off the Ford plug on a Chevy MSD dist that had been in a fire. been
awhile since I worked in the performance industry, so can't help
more than that. Guy I know is trying to adapt MSD dist to 747 ECM
controlled spark (yep, gotta lockout the timing next). 
So what does the Ford type pickup put out? Square wave? or more of a
ramp? Will the GM EST understand this signal correctly?
Tom

Bruce Plecan wrote:
> 
> From: Thomas Matthews <Tmatthe1 at worldnet.att.net>
> To: DIY-EFI <diy_efi at efi332.eng.ohio-state.edu>
> Subject: Square wave ingition triggers
> >Does the MSD distributor put out a square wave trigger pulse that is
> >compatible with GM modules and EFI? The MSD distributors look like
> >they use a Ford type pickup assembly if that helps..
> >TIA,
> >Tom
> 
> What for module do they use?..  What distributor part no.?.
> Cheers
> Bruce