[GreenKeys] Re: FAA dates

[wa2hwj@att.net]

We had a message center on Long Island that calculated
freight and fuel loads (from what I could gather). It had a
lot of 28RO's/ASR's and one high-speed BRPE. When the tape
shot out of the BRPE, it went out almost three feet
horizontally before gravity took hold. 
As far as a "message rejector": when certain guys in our
TTY gang worked on a slective calling 28, they turned
it into a "message rejector". It wouldn't copy anything!
It is a heart-stopping situation when you open up the
28 and find all of the tines from the function bars
on the bottom of the machine. A bad clutch would just rip off
every tine on the stuntbox...recoding was a nightmare.

Jack WA2HWJ

NNNN
> I've been trying to get around to answering this question.
> 
> The C.A.A., forerunner of the F.A.A. was into Teletype quite early for
> aviation weather reports.  I don't have a starting date.  In the 1940s
> they improved the system with ASID - Automatic Station Identification
> Device.  This was a box of relays, not made by Teletype, that worked with
> a modified Teletype XD that had the ability to run the distributor without
> feeding tape and had the tape sensing contacts and the distributor 
> segments brought out separately.  I believe a very similar XD was used
> with the 81D1 and some other switching systems, at originating stations.
> (An originating station is usually a station for originating messages
> right at the switching center, so you aren't limited to the single wire
> line between the center and the station.)
> 
> ASID allowed the operator to turn on his tape reader anytime during the
> transmission from the previous station in turn.  When the line went idle

> it would start the distributor, send the station identification letters
> from relays, and then send the tape containing the weather report.
> 
> I have a manual dated 1948 on Teletype Sequential Control (SECO) for
> the C.A.A.  SECO provided for a tape for polling the outlying stations.
> At each outlying station there was a SOTUS to detect the polling and
> send the weather tape.  Some arrangemently locally engineered by the
> C.A.A. provided for copying selected messages from one area circuit to
> another, using FRXD machines controlled by the SOTUS.
> 
> Then about 1959 the F.A.A. contracted with Teletype for a replacement
> weather system called ADIS, Automatic Data Interchange System.  This was
> a major project, brought on partly by the arrival of jet airliners and
> hence the need to get transcontinental weather data shipped around faster.
> Principal features of ADIS:
>   area circuits upgraded to 100 WPM using Model 28 equipment (and the
>     Model 28 stuntbox replacing the SOTUS)

>   area circuits are polled by a stepping-switch unit (not made by 
>     Teletype) called APULS, Automatic Programming Unit, Low Speed
>   a 600 wpm national backbone circuit linking all the area circuits.
>   traffic from the area circuits goes on to the backbone at 
>     interchange centers using low-to-high speed converters,
>     consisting of Model 28 reperforators and BX high speed readers
>     (and big reels for the tape supply and takeup)
>   interchange centers are polled to transmit by a stepping switch
>     APUHS, Automatic Programming Unit, High Speed
>   traffic on the backbone is selectively copied on to high-to-low
>     speed converters at the interchange centers, consisting of BRPE
>     high speed punches and LBXD readers
>   a magnetic core rope decoder at the interchange center recognizes
>     the station identification letters in the backbone traffic.  A
>     big plugboard with diode plugs turns on selected high-to-low 
>     converters to copy traffic from the backbone and repeat it into

>     the area circuits
> 
> Following installation of ADIS the F.A.A. contracted with Teletype for
> a message switching system called BDIS.  BDIS is sort of a pun on ADIS.
> ADIS was for the weather service, called Service A, and BDIS was for the
> flight plan and message system called Service B.  BDIS used a similar
> architecture to ADIS, a high speed backbone and low speed area circuits.
> The high speed part was spiffed up with DRPE tuned-reed punches and CX
> tape readers.  Since messages in BDIS are point-to-point the Model 28
> stuntbox is used to suppress printing on messages not needed at a
> particular station.  There were some things called message rejectors;
> and I haven't been able so far to find out what they did.  A guess is
> that they prevented messages from going on to the backbone if they
> didn't need to, such as messages where the origin and destination are
> on the same area circuit.
> 
> Then there was to be a system called CODIS, of similar architecture for

> Service C and Service O.  This system was cancelled during development
> as the F.A.A. chose instead to use a computer-technology switcher.  I
> think they used a Collins C-8400 computer.
> --
> 
> jhaynes at alumni dot uark dot edu
> 
>