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Old Dog Learning New Tricks

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spu3
 spu3
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Thoroughly enjoying DroneBot Workshop! I built my first computer (IMSAI 8080) back in 1976. I/O device was an ASR33 teletype. Non-volatile memory was punched paper tape. Current interests are my Arduino(s) and now figuring out my new Seeduino XIAO. Currently working on a LED bar graph monitoring system for my 1925 Studebaker bus.


   
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Posted by: @spu3

. I/O device was an ASR33 teletype.

Wow, that brings back memories!

I used to work for CNCP Telecommunications in Calgary and one of the things I had to repair was Model 33 teletypes. We eventually surplussed them in favor of the more "modern" Extel electronic units, which were based upon the Intel 8080.  My first home-built computer was based upon the Zilog Z80, and I used a model 33 as it's I/O device.

Welcome to the forum! You'll find a lot of "old dogs" here, so you're in good company - at age 61 I'm one of the "youngsters"!

😎

Bill

"Never trust a computer you can’t throw out a window." — Steve Wozniak


   
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codecage
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@spu3

There are a good number of us old dogs around!

My first computer was in 1975, an Altair 8080, with a whopping 1K (yes you youngsters, computers of old didn't come with much memory, unlike the 64GB model I'm currently using!) and at first my only I/O was the front panel switches for input and the LEDs for output.

I then acquired a Model 33 KSR from a local Teletype repair shop for drawing a schematic of its wiring for them (they had acquired a supply of them from a warehouse sale and had no documentation for them).  While they could have ordered documentation for them, it worked out well for me to get a machine for free.  I think they had gotten about 100 machines for just a $1.00 each, so they got a schematic for $1.00 in essence.  Much cheaper than ordering from the factory.

Then I had to get a RS-232 serial I/O board to interface the M33 KSR to the Altair.  And at this time there was only the 1K of static RAM in my Altair, no ROM, so every time it was turned off, everything the computer knew was gone.  When powered back up I had to hand enter from the front panel switches a small monitor program in 8080 machine code to allow me to use the M33 KSR as my input/output device.  Those were the days.  Glad they are a long ways behind us. 😎 

Making a long story even longer, I was trained in the USAF (1966-1970) as a teletypewriter repairman.  Although those machines used the Baudot code instead of ASCII to communicate with each other and they also used 120VDC at 60ma instead of the low voltage of RS-232.  One of my other hobbies besides what we play with here on the DBWF is keeping these mechanical wonders running and out of landfills and metal crushers so the younger generations can see the devices we used to use for "text" and "email."  I have a Python program that runs on a Raspberry Pi that I can use to send text messages from the keyboard of a Baudot machine to your smartphone, then when you reply it is received and printed on the paper in the machine.  My guess is there may be a good number of members of this forum that have never seen a Teletype machine.  Maybe I can help you out if you want one!  🤣 

SteveG


   
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huckOhio
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@codecage

Brings back great memories (except inflation and interest rates).  I was in the AF in mid 70’s and was a 30600/01/02 (I think those are the correct AFCSs) repairman.  That’s Crypto (voice and data – much of which was still vacuum tube technology), Digital Subscriber Terminal Equipment (DSTE – paper tape, punch card, printer, and common control unit), and teletype.   

As I got older I would explain to our IT/software engineers how easy they have it; that "back in the day" we had to load a boot-up sequence using 16 bat wing switches loading binary into 4 registers.  We had to clock in each set of commands manually and you didn’t know if you did it right until you hit the run switch.  No BIOS back then.  

Back then these systems we’re more mechanical and I remember the core memory boards (very large) that might have 1k of memory.  I was at NORAD in the 80s and I suspect that today’s gaming PCs have more computing capacity then the main frame computers that were in “the mountain”.   


   
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codecage
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@huckohio

Yes, 306x0 where the x was replaced with 1,3,5,7 & 9 depending on your skill level, rank and time in grade. The 7 level usually didn't happen before you made SSgt.  And hence the name for a small screwdriver with clip to hold it to your fatigue shirt pocket became "7 Level" as that was about the heaviest tool a 7-level technician ever picked up.  I made SSgt under 4 years, but was still at the 5-level rating.

I worked very closely with the 306 crypto guys in the secure comm centers I worked in during my enlistment.

SteveG


   
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robotBuilder
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This old dog was a conscript in the Signals in the last year of the Vietnam war.  My training included learning Morse Code and typing it on a teletypewriter as it came through the earphones. It was all stored on long strips of punched paper. Unlike you guys I spent the rest of my life working physically on the family farm where electronics and later programming was just an occasional hobby.

 


   
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huckOhio
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@codecage

I was staff in 4, but the same as you I was a 5 level.  I still have my "7 level" screw driver.  I also have the plastic screwdriver we used for alignments. Good memories. 


   
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