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Volume 28 : Issue 43 : "text" Format

Messages in this Issue:
  Re: Surge Protection 
  Re: TTY 33 and 35 case and cover composition?  

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Date: Wed, 11 Feb 2009 04:37:18 -0600
From: "GlowingBlueMist" <>
Subject: Re: Surge Protection 
Message-ID: <4992aa51$0$57677$>

<> wrote in message
>I have a need to add some surge protect a telephone system.
> I need the surge protection on the incoming circuits, right at the
> demark point. I have several lines including POTS voice lines, POTS
> dial in modem lines, VDSL, ADSL, and T1 circuits. Is there a surge
> protector that will protect all of the above lines without degrading
> performance?

Check with Mike Sandman's web pages.
I'm sure he has what you want in there somewhere, or send him an email.

His web page and catalog can be found at


Date: Wed, 11 Feb 2009 06:54:03 -0800 (PST)
Subject: Re: TTY 33 and 35 case and cover composition?  
Message-ID: <>

On Feb 11, 12:51 am, Michael Grigoni <>

> > # These are the hardcopy Teletypes from before AT&T bought the
> > # company, clattering electromechanical dinosaurs in Bakelite
> > # cases that printed on pulpy yellow roll paper.  If you remember
> > # these you go back a ways.  Teletype-branded VDTs are listed in
> > # the AT&T section.  

> I replied to the list that I was unaware of any Bakelite cased 33s
> or 35s and that the covers were made from a thermoplastic for the
> 33.  I received a reply that someone wondered if any 'hardened'
> versions had Bakelite cases.

As an aside, AT&T (through Western Electric) owned Teletype for many
years, I believe since the 1930s.

I believe the 'bodies' of Teletypes were steel with a glass insert.
The model 33 had a liftable cover which I suspect was plastic.

How does one differentiate between actual Bakelite and plain plastic?

While we're on the subject, was the model 33 impact impression
adjustable?  That is, how many good quality carbons could be made?

Many schools used model 33s to each comp sci in the 1960s/70s.  Could
a school have used a spirit "ditto" master form (the kind with the
heavy blue carbon sheet underneath, not mimeograph) to duplicate a
terminal session?  You need to press hard on those to get a clear
copy, and even then the results were faint.  [But before cheap Xerox
machines, that was the cheapest way for short runs (under 50 copies).
Long runs required the mimeograph machine which meant cutting a
stencil with a typewriter; they were messy!  The spirit duplicator
used a fluid to copy off the backside of the master, the mimeograph
bled the ink through the cut stencil.]

I got the sense that TTYs did not have a hard impact impression.  We
always used the pulp paper (for us, they gave us newsprint).  When the
TTY ribbon was too faint, I took them home and got plenty of more use
of them on a regular manual typewriter.

***** Moderator's Note *****

The Model 33 case was plastic, not Bakelite, which was too prone to
chipping and cracking to be used in a high-vibration environment such
as a Teletype machine. Earlier machine, such as the venerable Model
15, had metal cabinets.

The Model 32/33 impression strength could be adjusted only slightly,
but it was pretty high to begin with: carbon forms with up to two
copies could be used without trouble. The problem with carbon forms
was not the impression depth, but the "shoulder" impressions made by
adjacent characters on the typewheel used by the Model 32/33. The
Model 28/35, which had a type pallet with individually-struck slugs
for each character, could be used for thicker forms, with more copies.

Many schools _DID_ use the Model 33 as a terminal during the start of
the computer revolution, and that gave the 33 an undeserved reputation
for unreliability. School administrators, who weren't expected to know
any better, and system salesmen, who did know better, economized on
the terminals to close sales. The Model 32/33, however, wasn't designed
for service as a computer terminal, but rather for use in TELEX and
TWX networks: it was rated (IIRC) for 1500 "shaft" hours before major
overhaul. In TELEX or TWX service, that translated to years of
reliability. Computer users, especially children in computer labs,
placed much higher demands on the machines than they were designed to

Bill Horne
Temporary Moderator


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