Slightly OT: SR-52 Service manual

Rik Bos hp-fix at
Wed Sep 3 13:44:19 CDT 2008


The Ti-59 cardreader does not use a optical detector.
The SR-52 uses a switch to detect the card insertion and after that the
'opto' for card edge detection and write protection.
I suspect there should be some delay in the motor drive circuitry , to
ensure that card is pulled out far enough, to get it free from the capstand.
But I need the schema to find this out.
So ik some one has a copy or a scan of it, I would be very happy.


-----Oorspronkelijk bericht-----
Van: cctalk-bounces at [mailto:cctalk-bounces at]
Namens Eric Smith
Verzonden: woensdag 3 september 2008 20:08
Aan: General Discussion: On-Topic and Off-Topic Posts
Onderwerp: Re: Slightly OT: SR-52 Service manual

Rik Bos wrote:
> I'm bussy restoring a Ti SR-52 and having some trouble with the card 
> reader
> So I'm searching for a schematic diagram or service manual.

I had a paper copy around 1979, which wasn't too hard to get at the time.
IIRC, I just called TI's Lubbock, TX office and asked for a copy, and they
sent it to me.  I doubt that they have them any more, but if they were
easily obtained (unlike HP calculator service manuals), there are probably
people out there that still have copies.

The TI-58/59 service manual is more commonly available.  It's possible that
the card reader is similar enough for that manual to be useful to you.


More information about the cctech mailing list