Search Posts:

Restoration Complete

View Entire Thread

Return to Threads

  by Bill Degnan - 11/29/2012 22:33
Teletype model ASR 33 restoration complete. Pictured here is a view with some of the outer cover components removed. Click images for larger view.

I was wrong about the capacitor, I tried it in another teletype and it worked just fine. In fact I tested three caps so now I have a spare for the future. I also tested the motor relay (which works), re-soldered the UCC-6 controller card resistor joints, and replaced the UCC-6 itself. I found nothing wrong and I was still at a loss to determine why the teletype was running open in LINE and LOCAL modes.

Then I found the source of the problem. The BREAK key pin was out of its joint under the keyboard, just slightly, but enough to be constantly "on". I must have caused this issue when I vacuumed the insides of the TTY after running a long punch job without a chad catch cover on the punch pins. Note - don't ever try this.. What a mess!

By re-aligning the pin into its slot, the TTY now closes in LOCAL mode or when engaged by a computer system sending a current loop.

A new unit cover and punch chad catch cover installed. Click image for larger view.

Finishing touches:
1. I replaced the cover, paper advance knob, and re-aligned the papertape reader.
2. I tested the system using my SWTPC and PDP 11/05. For the first time I got a good print from the 11/05. (I will come back to that later).
3. Wayne D. sent me a papertape punch chad cover (triangular plastic thing) which I installed.
4. I read a long papertape (TSC BASIC) using the reader, successfully loaded BASIC, customized it, and punched the customized copy to tape.
5. I fashioned a new cable for the computer.


Took a few new pictures.



Buy a Commodore Computer Poster

Popular Topics and FAQs

  • Commodore B Series Tips and Tricks
  • Aerocomp TRS 80 M 1 Expansion Unit DDC
  • Items Wanted
  • Lobo Max 80
  • Zenith Z-19-CN
  • Prototype PET 2001 photo
  • Using Toggle Switches to Analyze Memory
  • Commodore Disk Archive Project
  • PET 2001 Prototype at Gametronics 1977
  • Jim Butterfield Photo
  • IMSAI 8080 With Processor Tech. Cutter
  • Secrecy is the keystone of all tyranny
  • Cromemco System Three
  • Northstar Horizon - Boot Problem
  • Computer History and Restoration Links
  • Commodore BX-256-80 - 8088 Co-processor
  • S-100 board testing with Z-80 ICE
  • Donner 3500 - an early portable computer
  • Digital (DEC) PDP 11/05 NC Assembly
  • Univac 1219 rescue
  • Fido BBS listing node list 6-13-1986
  • PDP 8e
  • MITS 88-2 SIO (2SIO) for BASIC
  • Visual Technology Inc Model 1050
  • Amiga 2500 Restoration
  • The Evolution Of IBM Computers
  • Replacement teletype print hammer head
  • Archiving and Copying Software 101
  • Computers Built 1940 - 1950
  • CBM B-520 (a.k.a B256-80 or B500 256)
  • RCA COSMAC Microkit
  • Commodore 64K C-116 Mods
  • MITS 8800b Turnmon 9600 baud
  • Catweasel, 8in and 5 1/4
  • Raspberry Pi as Gateway to Internet
  • Digital PDP11 late 1969 early 1970
  • PDP 11/40 72 inch cabinet model
  • PDP 11/40 Industrial 11 model
  • Digitial MicroVAX 3100 30 System
  • Digital VAX 4000-200
  • Commodore 64 / 1541 DRIVEKNOCK
  • Booting the System Using RL02 drive
  • PACS: Reflections by Kathleen Mauchly
  • Tele-Graphic Computer Systems Inc.
  • Commodore B Series SID Jukebox?
  • Installing Core into PDP 11/40
  • Setting Up OpenVMS 7.1 DNS CLERK
  • Felt-Tarrant Comptometer Model J
  • NextStation Color
  • Digital Rainbow (PC100-B2)
  • 1970 Compusad Compulogical Tutor
  • Archiving Papertapes Using DSI NC 2400
  • 1976 P.C.C. Features the MAI JOLT 6502
  • 1961 Beckman DEXTIR Computer
  • UNIVAC 1 and UNIVAC File Computer 1
  • Past Issues:

    Loewen TRS80 Hi res

    This image was selected at random from the archive. Click image for more photos and files from this set.