Hello and welcome to another episode of the 8-Bit Guy.
Today I’m going to be showing the Telstar call control system from 1983.
This was donated to me by Ben Langrill from Midland, Michigan, who received it as a gift
from his grandparents.
I’ve been getting a lot of really interesting donations lately, and this is one I’d never
heard of.
It has the AT&T logo on the top, but it says American Bell.
This is probably something to do with the fracturing of the phone companies back then.
However, it’s actually manufactured by Western Electric.
And that’s no surprise because the styling very much matches this traditional telephone
which is also made by….
Western Electric.
I know the title of the video says answering machine, but calling it an answering machine
is really an understatement..
Let me show you exactly what this thing does.
Lets’ imagine this simple drawing, and you have your phone line coming from the telephone
company, or as well called it back then Maw Bell.
It goes into your home.
Now, inside the home, the line usually splits off into several different rooms, giving you
many different phones that all share the same line.
Easy enough to understand, right?
Ok, so if you had a traditional answering machine, it would usually plug in before any
one of these phones, like this.
Now, although it does pass the signal through the machine, it doesn’t really do anything.
It’s more or less a convenience feature to save you from having to buy one of these
splitter thing-a-ma-jigs.
What the Telstar is designed to do is quite different.
So let’s re-think this scenario.
They want you to install this on your main phone line and then all of your phones will
connect to the Telstar.
You can kind of think of the telstar as having two sides to it.
One side takes the signal from the phone company and works as your answering machine.
The other side that goes to your telephone actually simulates a brand new telephone line.
It intercepts everything coming from your phone.
This allows you to pick up any phone in the house and control the telstar directly, but
this also allows it to actually place calls on your behalf, like a speed dial.
For example, it can immediately place calls to the fire department, the police, or call
an ambulance.
Keep in mind that back in the 1980’s we did have 9-1-1, but it wasn’t widely implemented,
especially in the rural areas.
A lot of people simply didn’t know about it.
And even in the cities it was still fairly common practice to just call your local emergency
telephone numbers.
It was not uncommon to have three separate numbers printed on a telephone for fire, police
and medical because nobody could remember them and it took a long time to look them
up in the phone book during an emergency.
So, another thing it could do was restrict access to long distance numbers or any naughty
telephone numbers, or basically any numbers you wanted to add to a block list.
Let’s take it apart and see what makes it tick.
So there appears to be two boards.
An analog board is on top here, with the logic board on the bottom.
It has a gigantic transformer here, which is where all of the weight comes from.
So it looks like if I want to see the logic board, I’ll have to remove this analog board
first.
All right, there we go.
So let’s have a closer look at this board.
From what I can make out, this is clearly the CPU.
It’s a 40-pin DIP package, which was commonly used by the 6502, Z80 and others.
However, this one has all proprietary markings on it, so I can’t determine what sort of
CPU it is.
This next chip here is a standard 2 Kilobyte Static RAM chip.
This is a Texas Instruments speech synthesizer chip.
This same one was used in many arcade and pinball machines, as well as the add-in speech
cartridge for the TI-99/4a home computer.
It is a close relative of the speech synthesizer that was used in the Speak and Spell.
These two chips here appear to be ROM chips.
This 12 pin chip here is a total mystery.
It has gold plated pins, but the markings are unfamiliar and a google search came up
dry.
So at this point you may be wondering how a simple 2 Kilobytes of RAM would be enough
to store several minutes worth of voice recordings.
Well, it can’t.
It actually doesn’t record any audio at all.
So you may be wondering how the heck it can be an answering machine.
Well, what it does do, is it allows the caller to type in their telephone number much like
you would have done with a pager, y’all remember those?
And then it stores all of the phone numbers that it has received over the day and it will
read those numbers back when you get home, or when you call in to check your messages.
Remember that mystery chip I was showing you earlier?
I have a sneaking suspicion that it is a DTMF tone decoder chip.
If you happened to be an unfortunate person who was still using one of these phones in
1983, which these were still in common use during that time, then you would not be able
to leave a message on the Telstar.
OK, so let’s hook this thing up and see what it does.
I actually don’t have a POTS line in my house anymore.
By the way, POTS is a slang term that stands for “plain old telephone service” which
is a way of explaining that you mean analog telephone service and not any sort of modern
digital or voice-over-IP system.
I do have a Vonage box, however, which does simulate a POTS line.. so I’m going to unplug
my phone lines and plug in the telstar here.
I’ll also plug in this old matching phone next to it as well.
OK, I’m just going to look through the manual here.
Looks like the first thing I may want to do is set the date and time.
record start.
press choice.
enter month number, then press pound.
0, 3 enter date, then press pound.
1, 9 press choice.
enter time, then press AM or PM, then press pound.
1, 1 ,4 ,2, AM, press choice.
record stop.
Wow!
I love the sound of vintage voice synthesizers!
The time is 11:42 AM, March 19.
Weird, even the dial tone sounds different.
Please hang up.
So, here’s another really interesting feature of the device.
As most people know, on these old-school POTS lines, there was no way to call another phone
inside your house that was sharing the same line.
First of all, there would be no way to make the phone ring.
But then even if you both picked up the phone at the same time, you’d have to talk over
the annoying dial tone, and eventually that tone would turn into this really harsh sound,
which is meant to alert you that the phone is off the hook.
But with the Telstar device hooked up, this is suddenly possible.
You can pick up any one phone, and dial a special 2 digit number, then hang the phone
up.
Then all of the phones in the house will ring a custom pattern, and when you pick up the
phones there will be silence and you can talk on them.
OK, so I’m going to call myself and I’m going to try leaving a message.
Hello.
No one is available now.
At the tone, please use touch tone dialing to leave your number.
OK, I’m just going to type some random number here.
OK, so now I’m going to check my messages from a regular phone.
The first call was from 5, 3, 8, 5, 6, 8.
Received at 12:38 PM, March 19.
So one concern a lot of people might have is what happens if you lose power because,
you know, POTS lines are powered externally by the phone company.
Well, there’s actually a relay in this thing so when power is lost, it actually goes to
a failsafe mode and it immediately routes all calls directly to the standard phone line
just as if it wasn’t even there.
So originally, this device was supposed to sell for $200.
Now, from what I’ve read online, apparently the market studies said that it was going
to be a flop and so they just decided at the last minute, right after they manufactured
a few batches of them to just kind of abandon the project.
So, they ended up marking them down and selling them off real cheap, and so they’re kind
of a pretty rare item to get ahold of.
You know, it’s really kind of sad because I think it’s actually a pretty cool device.
If you consider the state of home telecom back in the early 80s, this would have added
a lot of extra features that most people wouldn’t have had.
And I don’t think $200 was a ridiculous price.
It would probably be closer to like $400 in today’s money.
But again, you’ve got to consider the lack of telecom services back then, so, anyway,
I hope you found this episode interesting and I’ll see you next time!