[GreenKeys] Re: ASR-33 repair question (no carriage return)

[Don Robert House]

Robert,

In the adjustment manual is an adjustment for carriage return.  It 
has to do with a lever that operates a release near the left front of 
the typing unit.  Sometimes the lever binds and does not operate. 
Remember that the 33 does not have automatic carriage return unless 
it was specially modified with a kit for that purpose.

The typing unit needs to receive a carriage return code which 
operates a function lever that releases the spacing pawl, which then 
allows the "door spring" to return the carriage to the left.  The 
sequence is Carriage Return (CR), Line Feed (LF), and Rubout (RO) at 
the end of each 68 to 72 character line.  If the CR is not received 
in the selector, the 73rd character will then over-type the 72nd.

A problem associated with M32, M33, and M38 is the fact that all of 
the machine's 8 level contacts are in parallel and are sent to the 
distributor to serialize them for the selector mechanism.  If any of 
the contacts bounce during the operation of the machine a "garble" 
will occur.  The most critical adjustment on these machines is the 
"H" lever adjustment between the keyboard and the typing unit.  It 
looks more like an "X" near the right front of the typing unit.  The 
best tools for this adjustment are a nut driver with a long shaft and 
a medium sized straight blade screwdriver with a long shaft.

If you need more information on the adjustments there is a fellow 
selling a CD-ROM on ebaY with all of the M33 Technical Manuals on it.

Regarding the 33 with the eaten wiring.  I would suggest removing the 
typing unit. Lubricating it and storing it in a plastic bag.  The 
machine will be valuable for parts.

Hope this helps.

Don


>Don,
>
>Hi, I got your name/email from David Weil at the San Diego Computer 
>Museum of America.
>(After being impressed by the huge collection of Teletype stuff there.)
>He thought you might still be open to answering questions...
>
>I have an ASR-33 (from eBay) whose carriage does not return.  :-(
>It reaches the right side and just keeps overtyping there.
>
>I've oiled and lubricated the unit, according to the maintenance manuals.
>(What a procedure!)
>
>Any thoughts?
>
>Thanks,
>
>- Robert
>
>p.s.  I also have a 2nd ASR-33 that was in "storage" for many years.
>The mice apparently found the wires appetizing...  :-(
>
>p.p.s.  I'm an active member of the Computer History Museum in 
>Mountain View...


-- 
---------------------------------------------------
Don R. House
4716 Patty Lane, Ringwood, IL 60072
Tel: 815-653-0683
FAX: 815-653-0684
*****************************************
North American Data Communications Dept. of CMA
URL: http://www.nadcomm.org
Computer Museum of America (CMA)
URL: http://www.computer-museum.org