[GreenKeys] Manuals Available

[Jim Haynes]

On Sat, 14 Apr 2012, Charles Ring wrote:

> I think this has been covered before but I forget: How was there a model 31
> 10+ years before the 28?
> 
That sort of things comes about for a couple of reasons.

1.  The numbered models are a Bell System thing.  Some Teletype equipment
     did not have model numbers because it was not built for a Bell System
     requirement.  An example is the circa 1930 stock ticker.

2.  When a model number is chosen, it may be very early in the development
     cycle.

Model 26 was produced in the late 1930s.  Model 27 was assigned to a 
military machine based on the Model 26 which was never produced.  It was 
Teletype's entry for the TT-4/TG; and the Army liked Kleinschmidt's 
submission better.  Development of Model 28 goes way back, at least to 
1941.  The Model 29 number may have been assigned at the same time as 
Model 28, to apply to a proposed upper/lower case machine in the line, a 
replacement for Model 20.  The earliest manual I have on Model 31 is dated 
1947 and is Issue 1.  So maybe it was not developed until after WW-II, or
at least until after the Model 28 was well underway.

Another funny is that the last stock ticker produced used Model 37
technology, but was officially called Model 28.  My guess is that AT&T
wanted to keep the Model 37 name pure for the product they intended to
market, and didn't want people to make the connection that the technology
had already been used previously.