MOTM-120 Mod suggestion

[<<marjan>>]

> I think the "T" in "HCT" implies that the inputs of such devices are
> voltage-level compatible with TTL logic.  I noticed that many vendors
> are only carrying the HCT parts now, since (perhaps) they can always
> substitute for the HC versions.  If anyone knows otherwise, please inform.


HC has output logic levels compatibile with TTL, but inputs aren't 
with TTL output levels ,so HCT is modified to lower treshold of 
CMOS so inputs are compatibile to TTL (treshold reduced from 2.5 V
to 1.4 V). Also it has better noise margin. There's also small
hysteresis (sp?) in it's transfer function.



marjan