TPC-I back in one piece (was Re: TeleVideo progress)

[Ian S. King]

On Sun, Oct 2, 2016 at 8:20 PM, jim stephens <jwsmail at jwsss.com> wrote:

>
>
> On 10/2/2016 6:23 PM, Ian S. King wrote:
>
>> Hi all,
>>
>> I've posted looking for help with a TeleVideo TPC-1, and I've heard a lot
>> of crickets <snip>
>>
> I saw your FB posting, good job, and chirp chirp.
>
>>    I've ordered an exact, tested/guaranteed
>> working replacement from ePay,
>>
> Those were common drives, but be sure to do a careful inspection, as some
> of the drives had variants that were subtle.
>
> good job, great you got it working.
> thanks
> JIm
>
>>   and I'm going to have everything working to
>> spec before I snap this thing back together.
>>
>> Yes, I'm having fun.  :-)
>>
>> OK, my 'new' Teac drive arrived and passed inspection.  I carefully
jumpered it to match the original, reassembled just enough that I could
plug it in, and... success!  So to recap (pun intended), the machine had
bad caps in the power supply (leaking goo) and a bad drive 0.

What I want to record here for posterity is how to open one of these
things.  It was a real pain, which I've heard was intentional.  Reassembly
was challenging, too, but at least I could see what was happening.  So here
goes:

To disassemble, you need to remove four screws.  Facing the unit as it sits
on the bench (i.e. operating position), there are two screws on the top of
the machine at the front corners and two others on the rear, vertically
centered and near each vertical edge (one of them is in the recess where
you can store the power and keyboard cables).  Now it gets fun.

The unit disassembles into a top cover that wraps over side-to-side, and a
rear piece that holds the majority of the electronics.  The bottom piece of
the main case holds the power supply, floppy cage and some of the video
electronics.  There are plastic 'teeth' that fit into indents at various
point along those pieces.  For the top cover, the 'teeth' are part of the
cover, one per corner.  For the back panel, the teeth snap into the top and
bottom of the main part of the case.  The teeth are also accompanied by a
very thin indent in the case piece.

It's sort of a muscle job to get these things separated.  I got the back
piece free before removing the top piece, with a little help from a putty
knife in those indents.

There are screws in the bottom of the case that hold in the power supply
and the floppy cage  One of the floppy case screws is located underneath
the tilt 'foot'.

Putting it back together: be sure you have the logic board *inside* the
screw points for the back panel, but don't put in the screws yet.  Seat the
top cover with its teeth in place, and insert the two front screws (don't
screw down tightly yet). Then, lever the back panel's teeth into their
slots, watching the top cover to be sure it doesn't try to pop off.  Insert
the two rear screws and tighten.  Now tighten the front two screws, and
it's back together.  It may take a little jostling to get everything to
reseat completely.

Now to go through the metric butt-ton of software I got with this thing -
over a hundred floppies.  Looking at the labels, some are duplicates, some
are 'working' disks, and some are original TeleVideo floppies with system
software.  Fortunately, one of them is Kermit, which will make the
archiving job a lot easier!

OK, that was fun.  Next!  Probably the Kenwood TH-77A I bought that won't
transmit.  Cheers -- Ian

-- 
Ian S. King, MSIS, MSCS, Ph.D. Candidate
The Information School <http://ischool.uw.edu>
Dissertation: "Why the Conversation Mattered: Constructing a Sociotechnical
Narrative Through a Design Lens

Archivist, Voices From the Rwanda Tribunal <http://tribunalvoices.org>
Value Sensitive Design Research Lab <http://vsdesign.org>

University of Washington

There is an old Vulcan saying: "Only Nixon could go to China."