Modems and memories

A few days ago, a friend mentioned Galacticomm and their bulletin board system the Major Bulletin Board System.

From the depths of memory, my CompuServe account number and password appeared. And that led me (and now you) on this trip down memory lane.

BBS Systems

BBSs were a big thing once upon a time. Those of you who have only lived in the internet age may find the history of connectivity interesting. Or boring. Whatever.

You could create a BBS system if you had a PC, a bunch of phone lines and an equal number of modems. You might want to start with a PC with a lot of memory. Instead of the 640 KB standard limit, you could get a Phar Lap memory expansion that moved you up to 16 Mb.

That’s megabytes, kids. Not gigabytes. Wow!

Each phone line and modem gave one user access to your system. With a standard PC you could support—well, two users.

But with specialized hardware, you could get up to sixteen.

Sixteen users! At once. All you needed was 16 phone lines and 16 modems.

Wow!

CompuServe

My CompuServe account number and password were. 72520,2747 and GENUS/BUREAU.

Where did that come from? Where had they been hiding? Could I have remembered them if I’d tried? No idea.

But here’s the CompuServe story.

You connected with CompuServe by dialing a local access number, sticking your phone’s handset in your modem’s acoustic coupler.

Acoustic coupler? Don’t know what that is? Acoustic couplers looked like this:

I was an early adopter. I think my first modem was 110 baud. What’s a baud? A baud is roughly a bit per second. At higher baud rates, you can transmit more than one bit per baud, but we never reached them. DSL modems today might.

Doing the math

How fast is 110 baud? If each character takes 8 bits, 110 baud is 825 characters per minute. Some of those characters are channel control, so the effective speed is less. And if your phone line is noisy, even less. But let’s be optimistic and think that it’s about 800 data characters per minute.

An average person can read at more than 200 words per minute—roughly 1000 characters per minute. I’m well above that. So my first modem under best conditions was much slower than my reading speed. Probably slower than yours since you are probably above average.

And images? The picture of the acoustic modem isn’t that big Just 75Kb. That’s 11 ½ minutes at 110 baud. And the megabyte images we’re used to? Don’t wait up.

Faster and faster

Things changed.

Can you imagine how excited we were when the modem standard jumped to 300 baud? Three times as fast. Then, just a few years later to 1200 baud? Four times as fast? Then to 9600 baud. My first 9600 baud modem was big—about 16 inches square and one or two inches high and it cost more than $1,000. And that’s when $1,000 was real money.

Eventually, speeds got up to 56K and sizes went down. 56K modems were on a chip in your PC!

Astounding, right?

Music to my ears

When modems connected, the modem board would let you hear them negotiating protocol, and once they agreed, the board would shut off the sound. If they didn’t, then the sound would go on forever.

This is the sound of progress as modems got faster:

And here’s the full experience for a high-speed modem:

The sound of silence

The sound of modems connecting was music to my ears.

But the sound of silence meant you were connected.

Nothing better than the sound of silence.

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