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

 -=> Roy J. Tellason said to Greg Mayman
 -=> about "BAG OF CHIPS" on 01-14-04  04:06.....

 RJT> This wasn't my doing,  though.  Reminds me somewhat of assortments of
 RJT> stuff I've seen at some hamfests.  It was similar to the bags of
 RJT> resistors I had enountered a while back,  too.  And it's close to being
 RJT> a fairly generic assortment of parts,  too,  except for that 565 chip. 

 GM> Yes, that's the puzzler if that package was intended for one
 GM> particular project.

 RJT> And those zener diodes. Why 5.1v when there's no logic anywhere
 RJT> around? 

 GM> Why not? With a lot of jobs you need some kind of stable
 GM> reference. If you have TTL logic somewhere in the system, 5v is a
 GM> already there so you use it. If you want the same design in
 GM> another project that doesn't use TTL anywhere, using the same
 GM> voltage means you don't have to redesign.

 RJT> Yeah.  I still have a "709" or two around,  and maybe an
811 (which
 RJT> I'm sure nobody has ever heard of),  stuff like that.  They were
 RJT> actually considered superior to the 741 for some uses,  though I can't
 RJT> recall which uses those were offhand.

 GM> The big advantage with the 741 was that it was internally 
 GM> compensated down to unity gain.

Yeah,  I remember seeing them and thinking "Now I don't have to bother
with _THAT_ any more...!"

 GM> The big DIS-advantage was that this compensation limited the 
 GM> slew-rate to something like 0.5 volts per microsecond typical.

In those days I was a little fuzzy about what slew rate implied.  :-)

 GM> So if you wanted to swing the output to near full rail voltage,
 GM> that's a 30v swing on a +/-15 supply, you would run into
 GM> slew-rate limiting from about 8KHz up, maybe lower in chips with
 GM> worst case specs.

They were still useful,  though.  And really,  how often do you need that
wide a voltage swing in most stuff?  I can remember running into it fairly
seldom, the one big exception being in early analog synths where a 10 volt
p-p waveform wasn't all that uncommon.  Most audio stuff is at a lot lower
level, until you get into power amp stages.  I guess this is of more
concern with other uses...

 GM> With the 709, all the compensation was external, so you would add
 GM> just enough to make it stable at whatever gain you were designing
 GM> the circuit for. So the slew rate could be typically ten times as
 GM> high for a gain of ten, and still keep it stable.

 GM> At least that's how I remember it.

Yep.  Sounds about right to me...

 RJT> 500KHz?  Hm.  Not that much,  really,  though with all the tricks that
 RJT> get wrapped around PLL circuits that doesn't mean that it's not useful.

 GM> There aren't many integrated PLLs that work a lot higher. The 4046
 GM> only goes to 0.7MHz typically.

Oh?  I hadn't looked at that bit in the spec.  I've also been bumping into
some other numbers lately,  Motorola stuff with six digits after the
"MC" prefix,  I can't recall the rest of it offhand.  These would
typically have lots of prescaler and divider stages in there to mess with, 
so the input frequency could go a lot higher.  Applications typically
seemed to be in things like CB radios,  VHF,  stuff like that.

 RJT> What would you do with one of these?  :-)

 GM> One use is PLL synchronous detection from the 455KHz IF in an AM
 GM> receiver.

 GM> I haven't tried it myself, but they say the distortion can be at
 GM> least as low as that of an FM receiver.

Hmm.

 GM> And you get ZERO adjacent channel interference, which has always
 GM> been the bugbear of AM receivers.

So it'd be good for picking up a weak and distant station that was close in
the band to a stronger and more local one?  Interesting stuff!

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