On Friday (06/05/2009 at 09:55PM +0100), Tony Duell wrote:
>
> I also have a 733 without cassette drives (is that a different model #)?
> It would be nice to have access to the service manual for it. It's been i=
> n
> an attic for about 10 yrs but I plan to bring it back to life real soon.
My mistake-- I just fetched the unit from the attic and it is a model
725 not a 733. Sorry for the confusion.
Although it was described as a "portable data terminal" and it is built
into a large suitcase. One really has to question the definition of
portable :-) Man that thing is heavy.
And to answer Lar's question about the picture, mine does indeed look
exactly like the one here,
http://www.digibarn.com/collections/systems/ti-tymshare-100/DSC02096.JPG
except that there are no Tymshare logos on it and the metal plate just
below the acoustic coupler does not extend all the way to the front.
On mine it is only about 2" wide with the carrier detect light directly
centered on that plate. Mine also unfortunately, has more of yellow green
color now instead of the greenish-grey it was originally. Time takes
it toll.
It's most definitely a model 725. Serial 725-11237. Part 954783-1.
I'll certainly take a look at the service manual
if it ends up on
Bitsavers or somewhere similar.
So, I will need to track down a model 725 service manual. The user's
manual is still inside the top cover so that is good.
I haev 2 of these terminals... At a radio rally nearly
20 years ago I
bought a KSR version (no tape drives). The seller had 4 old printers, he
started off trying to sell them for a farly high price (\pounds 10.00
each or something), by the end of the take he too \pounds 5.00 for all 4.
The one I particularly wanted was the Teletpye KSR43, the others with the
TI 733 and a couple of Cnetronics printes (brand, not (just) interface)
with a strange carriage feed mechanism. At the same rally, from another
seller I bought the dual tape drive unit. I didn't realise it would go on
the TI terminal until I got it home, saw the TI logo all over the tape
drive parts, and relaised the 'feet' would fit on top of the terminal if
I remvoed a couple of cover plates. What I didn't have was the cable to
link them. Oh, the tape unt is missing the outer cover but otherwise
seems to be complete/
Anyway, about 10 years later a friend of mine had the ASR model, complete
with covers and cable. I asked if I could 'buzz out' the cable and he
gave me the complete device.
Now that is a _good_ friend.
So I have one complete ASR model, a KSR one, and the
working bits of a
tape unit.
Oh-- it has a 300 baud acoustic coupler on the side too :-)
I don't have that.
Mine's still there. With the giant "CARRIER DETECT" light-- not LED of
course-- right below it.
The unit actually powers up and it still types!! Even the paper wasn't
totally black from 10 yrs of heat in the attic. Amazing.
However, the paper does not feed correctly. On inspection, I've already
found that the grease in the little solonoid that lifts the head from the
paper when it advances has turned to something more sticky than honey.
I'm in the process of addressing that.
I also see that the stepper motor that actually turns the platen (or equiv
of) is not making a full increment each time. Sometimes it advances but
other times it de-advances. So, something it messed up in the stepper
circuit or the grease in that stepper motor has turned to honey too.
This is a really cool machine though. I grew up with this thing hooked
to my first computer (an MEK6800D1 eval board) in 1975. I went through
thousands of rolls of thermal paper as I typed in machine code to MIKBUG's
'*' prompt one line at time :-)
There's no microprocessor in the thing-- not even a UART. It's all done
with 7400 TTL and electronically, it's extremely fixable.
It's pretty funny but as soon as I took the lid off the Silent 700,
the smell of that plastic brought back the same impressions of coolness
and excitement I had as a kid.
Everything else is on the back burner now-- gotta get this baby
printing right! :-)
Chris
--
Chris Elmquist