Greg Mayman wrote in a message to Roy J. Tellason:

 -=> Roy J. Tellason said to Greg Mayman
 -=> about "BAG OF CHIPS" on 01-28-04  04:06.....

 RJT> Dunno what the difference is between that and the 1458, 5558, whatever
 RJT> the heck it is.

 GM> Lacking any data sheet on it, and trusting to my untrustworthy
 GM> memory, I think the 1458 was a direct replacement from Motorola --
 GM> couldn't use the same number, could they? Motorola were like that.

Much went on with numbers back when.

 GM> Their 4000 series CMOS chips all had the prefix MC1. I came
 GM> across an MC4040 chip at one time that turned out to be a TTL phase
 GM> detector IIRC. It was nothing like the CMOS 4040.

I have one of those too,  they used one in the C64,  the MC4044.  The thing
was that Motorola had their own versions of TTL out back when,  using
MC3000 and MC4000 numbers,  around the time that TI came out with the 7400
series stuff.  I have an old Motorola data book from back then,  missing
its front cover so I don't have a date,  that lists
"MC3100/3000", "MC4300/4000", "MC5400/7400",
"MC8200/7200", and "MC9300/8300" series.  They also
call out "MTTL 1 MC500/MC400 Series",  "MTTL II
MC2100/MC2000 Series",  and "MTTL III MC3100/MC3000 Series".

From the cross-reference info at the front of the book there were
apparently also a number of other mfrs making TTL around that time,  each
of them using more numbering systems and of course different letter
prefixes.

Motorola did make some 54xx/74xx parts,  and I guess that's where the
industry eventually ended up standardizing but they _did_ use the 4000
series numbers for some TTL.  Because of that,  when they found out that
the 4000 series CMOS parts (from RCA originally?) were becoming equally
popular,  they had to call their version of it something else.

 RJT> I think I may go to AC coupling next time I start messing around with
 RJT> those 4066 chips.  I was going to try split supplies,  but then you
 RJT> need a +5/-5 logic swing for the control voltages and I'm not sure I
 RJT> want to go there. 

 GM> Where is the audio coming from and going to?

I hadn't really decided yet.  :-)

 GM> I mean what supplies does the other equipment use? If it already 
 GM> has a split supply it is easy to derive the +5/-5v from that.

Deriving the supplies wasn't the issue that much,  it was more a matter of
funny logic levels.

 GM> And you could use level translator chips - the 4049 and 4050 will
 GM> do that for you. Or a two transistor buffer will also do it.

If I'm remembering right they'll take a higher-range logic level swing and
translate it down to somewhat lower a range,  but that's not what I need
here, I'd need something that would take a zero-based logic swing and
translate it to a bipolar one.  There's probably some simple way to do this
but it's not apparent to me at the moment.

 RJT> Oh really?  That's pretty bad,  10K isn't that much of a load.

 GM> That chip's single-ended output used an external 4700 ohn reistor
 GM> as a collector load. As we were feeding the output to the 10k
 GM> fader, via an audo switch, as well as to the cueing circuit via
 GM> another switch, the output was fairly sensitive to extra loading.
 GM> But a 741 (or 1/2 747) as a buffer fixed all that.

Ah.

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