[GreenKeys] Fw: Building a KSR using today's technology?

[Keith Mc]

My early entry into that tech was a combination of:

- My ASR 33 Teletype, with a homebrew RS232-loop interface and +/- 12V power supply
- a 110/300 baud acoustic coupler (mickey mouse ears on top, for a handset),

Upgrade 1 was adding:
- a cassette tape recorder
- a hacked telephone handset - speaker with miniplug, and mike with miniplug
for connecting it to the recorder.
- a telephone suction cup pickup coil, for sticking onto the earpiece of a desk phone.
- an original ATT desk phone.

Upgrade 2 was adding:
- a Televideo 910 terminal.

The acoustic coupler could flip the orig/ans tone set, with a switch.

Many of the dial-in time share computers I worked with used
the 300 baud tones, but could still be configured to transmit and
receive DATA at 110 baud.

This set of tools served me for many years.
The original ASR-33 and modem setup allowed me to print out and
punch paper tapes, to save my programs and data.  

The upgrades allowing me to save a LOT of paper, and 
eventually paper tape as well.

Originally, I called up the computer with the ASR33, and listed 
my programs with the punch on to give me a "machine readable 
hard copy" of my programs.  I could later read them back in to 
a new time-sharing computer simply by opening up a text edit 
session, then hitting CTRL-Z once I was done.

This served me well through college and a few jobs, to port my
data and programs around at 110 baud, and to keep copies of them.
Many a night I let the ASR-33 run all night long, printing out
my programs and text files, and punching tapes of the things
that I wished to put back into the next machine I was on.

Yea, the UC only was a pain at times, but I could "fix things"
on the new computer a lot faster and easier than type them 
in from scratch.  Many of the computers had UC/LC conversion
filters, that could shift files back and forth easily.
(Shift an UC-0nly file back to LC, then fix sentence capitalization, etc.)

I later upgraded the TTY with the the audio cassette tape 
recorder, the pickup, and the hacked handset.  
This saved paper tape, by shifting to audio tape. (MUCH cheaper,
for a poor student, AND easier to find).

The second upgrade to the Televideo CRT gave me 
DIY **300** baud record (storage), and playback.  

With either the TTY or the CRT, I could review the tapes simply 
by attaching the hacked phone handset into my cassette 
recorder to simulate the phone line, setting the ans/orig 
switch correctly, and viewing them with the CRT tied to the modem.

A Hybrid of the two was to set the computer to SEND/RECEIVE
DATA at 110 baud, but still use my 300 Baud modem.  
Yea, this slowed the session, but it allowed me to attach the 
ASR-33 to the modem via the RS232-loop interface, and PRINT 
OUT the data saved on audio tape, or punch a paper tape from 
the audio tape.

Alternatively, I could use my early micro board, to create a 
300-110 baud printer buffer (and/or a 5-8 level converter).

But RAM chips were still small sized and expensive back then.
As I had little RAM, and so it had too small of a buffer.  
That gave it very little utility beyond giving me short print 
"snapshots" of my tapes, before I overflowed the small RAM.  

It was easier to just look at the cassette tape data on the 
CRT screen, and pause the cassette as needed while 
I re-typed whatever I wished to transfer back into the 
ASR33 as needed, to make a fresh paper tape.

This whole cobbled up system allowed me to keep all 
SORTS of data on the various machines I was on, at jobs, 
school, etc, yet be able to pull it all back out in 
"machine readable formats" for my next location before
leaving that place, even though the two machines would
never be able to talk to each other directly.   

That even "saved my butt" several times over the years.
Whenever a machine lost my data, I still often had my 
local copies, that I could "quickly" feed back in...
(Hey, 10-30 char/sec is a lot faster than *I* type! :-)

In the pre-internet days, that gave me a several DECADE
jump toward something akin to how we NOW normally 
do things, with desktop publishing, keeping data in text 
files, etc...and emailing them to ourselves, FTPing 
them from one machine to another (or uploading and
downloading them to/from archive sites on the net).

I believe I still have all of those parts today, buried
in various storage boxes.  Even my old ASR-33 is still
setting in my basement (though it needs a go through someday.
...Something went mechanically wrong with it, from bouncing
around in a mini-trailer during a previous move...).  


Though acoustic coupler and audio cassette tape 
"saving techniques" are no longer useful NOW, 
for MANY years "way back then" BF ("before floppies" :-), 
it was a VERY useful (and often the ONLY) technique 
for both moving data between machines, AND keeping 
reviewable yet "machine readable" copies for myself.

- Keith Mc.
"I have the oldest typewriter in the world. It types in pencil." - Steven Wright