George White wrote in a message to Roy J. Tellason:

 RJT> Let me look...

 RJT> They were LM310.

 GW> Right. Nationl Semiconductor chips, for which I happen to have a
 GW> data book (useful this _real_ book library at times like this ).

I've got one of those too,  that I bought at of all places Radio Shack! 
There was a short time when they actually sold such things...

Other than that, my databook collection is pretty sporadic,  I got 'em when
I could,  and there are a lot of gaps,  which is why I'm collecting
datasheets in pdf format these days.

 GW> LM110/210/310 Voltage follower.



What I don't understand there is why I'd want to use one of those rather
than just use an op amp connected in a unity-gain configuration...



 GW>> From the Signetics data book (Hardback dated 1974!): 

Hardback yet!  :-)

 GW>> "The SEW/NE565 Phase-Locked Loop (PLL) is a self contained, 
 GW>> adaptable filter and demodulator for the range 0.001 Hz to 500 
 GW>> kHz. The circuit comprises a voltage-controlled ocilator, an 
 GW>> amplifier and a low-pass filter..."

 GW>> Applications: Frequency shift keying Modems Telemetry receivers
 GW>> Tone decoders SCA receivers Wideband FM discriminators Data
 GW>> synchronisers Tracking filters Signal restoration Frequency
 GW>> multiplication and division.

 GW>> The application section of the data sheet has as examples: FM
 GW>> demodulation Frequency shift keying Frequency multiplication SCA
 GW>> (background music) decoder

None of that stuff suggests to me anything that *I* would want to do with
this part,  though.

 GW>> There is much more stuff in the applications book (also hardback
 GW>> dated 1974!)

 RJT> No doubt those references wouldn't contain any URLs to where I
 RJT> could find some of this stuff. I'll have to poke around some,
 RJT> see what I can find. Offhand,  though,  I cna't see where I'd
 RJT> want to build anything in any of those categories at this point
 RJT> in time..

 GW> Back in those days, as you ought to remember , none of the
 GW> companies had a BBS, and commercial Internet was still an
 GW> outlandish vision for the future.

Of course.

 GW> However, any contact data that's 30 years old isn't worth 
 GW> following up. Especially given the changes of ownership of 
 GW> semiconductor companies over the years...

It's also interesting to see what other companies are now supplying numbers
that you "thought" were owned by somebody else.  I thought
Motorola was the one that used the MC prefix on chips,  for the most part, 
for one example,  but a bunch of those data sheets I have are from some
Japanese company.  And there are numerous others.

 GW> However I'm sure if we really wanted to I could scan the stuff in
 GW> and get it to you...

That's okay,  I'll run into something sooner or later that I can use the
part for,  and in the meantime I've got plenty else to keep me busy.

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