PDP-11/20 vd one that just says pdp 11 what are the date differences?? OEM?

[COURYHOUSE at aol.com]

In a message dated 2/22/2016 11:50:15 A.M. US Mountain Standard Time,  
cisin at xenosoft.com writes:

On Mon,  22 Feb 2016, Paul Birkel wrote:
> I wonder how long it took them to  "figure it out"?  I seems that the
> family-plan dates to April  1969.

When everybody realized and accepted that there would be more  than one 
sub-model, and decided that it might be handy to be able to tell  them 
apart.  There may have been some holdouts in some departments,  such as 
silk-screening the panels.


By analogy, the phrase  "single density" didn't originally exist.
After "DOUBLE-density" was  developed, THEN "single density" needed a name.
Although just sticking with  "FM" and "MFM" would have been a lot better!
(Although I guess that it was  inevitable that marketing would invent "HD", 
instead of "double data  transfer rate MFM".)

There were even a few companies that freely  intermingled HEADS V density!
Intertec/Superbrain decided to call their  5.25" 40 track DSDD, "QUAD 
density", because it was twice the capacity of  the 40 track SSDD!  Then, 
when they added an 80 track DSDD, they  caalled that "SUPER density", 
abbreviated "SD"!  So, if you encounter  an alien disk labelled "SD", it 
might be 720K/800K, not  100K.


Similarly, if you were to search ancient archives, the phrase  "World War 
TWO" was first used BEFORE there was any mention of "World War  ONE".
It wan't until a second happened, or was expected, before anybody had  any 
reason to declare the "Great war"/"World War" to be "nuber  ONE".


So, the use of any sort of "first" name doesn't occur until  "second" is 
expected.



Or  WW1  was also referred to as the "war to end all wars"
 
 
some  good   name sequence  comparisons   here
 
Ed#