odd tech question

[kumakami]

OK I had a brain storm for a game setting but need some help. All good fiction is based in reality, you need the box first in order to think out side of it. I love steam-punk and had an Idea for an analog computing system using; mini pneumatic cylinders for its processor, magnetic audio to data recording using 16 channels each broken down to { low wave, mid wave, and high wave or, treble, mid, and base}, the mechanical tv as a screen, a glorified D-pad as a mouse, and modified type writer setup as a key board. the telegraph is the base of the net.

if in each sec. the data recorder can send/receive 10 segments of 16x3 date, that comes to 480bits per sec.

here is the help part, I'm trying to figure out what computer that's equivalent. I want a minimum of a apple 2. Help me!

[trodgers]

Fascinating question but 100 million miles outside my area of specialty. Something tells me that Brainwipe can help you out. Good luck!

Edit: Brainwipe is Rob Lang on here.

[Chainsaw Aardvark]

I've got some friends who are certified to fix computers, they might know. However, the question is - how many bits per second of what? Are you looking at the RAM and how big a program it can handle, or how many operations a second it can process?

I would suggest you look up - one of the first 1940s digital computers. The Charles Babbage [url-http://en.wikipedia.org/wiki/Analytical_engine]Analytical Engine[/url] may also be some good inspiration - but any good steampunk should already know about that.

For the sake of argument, the slowest modem I recall is a 1440 baud telephone cradle type (think the movie Wargames) However, apparently in the 1940s, IBM had a 25 bits/second - so 480bits/sec is probably still 1950s.

However, I'm not an expert, just guessing where to look on wikipedia. I guess just look at the specs for now.

[kumakami]

the 480 bit/sec is not processing but the data storage (aka disk/CD-ROM/tape drive) communication speed. This is about speed of transfer with in the computer so...CD-ROM and Hard-drive communication, not processor speed or storage capacity.

no matter how fast your processor is, if the information get to it slowly it can only move so fast.

[Chainsaw Aardvark]

[kumakami]

if you want to see more of what I'm talking about look up; Valdemar Poulsen and his 1898 invention Telegraphone. this is what the tape player is based on....damn cool

http://www.amps.net/newsletters/issue27/27_poulsen.htm

[BubbaBrown]

I'd look into microcontrollers. There's a whole variety with various abilities and features.

If you are looking into actually making a functional concept of this idea, check out the Arduino platform.
http://www.arduino.cc/

Pneumatic cylinders could easily replicate the basics of transistor based digital circuits and have memory. Transistors are practically working off the "pressure" that electrons create anyway.

The 16 channel data recording and reading could be emulated by a collection of Analog-to-Digital and Digital-to-Analog convertor pairings. Everything else can be easily emulated.

The Apple IIe and higher is pretty close to your concept as it is. The Apple II series (and a few others like the TRS-80 and Commodore 64) had the ability to load data straight from an audio tape feed and also record it, too. They used encoded tones across two channels of a standard audio tape to store a fair amount of data at a decent speed back then.

The Apple IIe used standard NTSC signalling to a screen... which is pretty simple when you break it down. The circuitry picks up the sync signal to trigger the electron beam to scan row by row, and the intensity changes according to the variations of the signalling between the syncs. Fairly mechanical.

The Apple IIe joystick ports were just Analog to Digital Converters (or just TTL digital ports, I forget). Simple signalling there.

The only trouble with the type writer is just figuring out how and where to wire all the micro-switches.

So... Yes, the Apple IIe would do it.

[Rob Lang]

If 480bps is your bus speed, regardless of how good your memory or drives are, that's how fast your computer is going to run. The processor can only run at the speed at which data is fed to it.

If we assume that it's an 8 bit machine, 480bps is 60 bytes per second. On the early machines, one instruction was usually* 3 bytes (instruction, memory address and data). So that's 20 instructions per second. Or, to put it in modern computing terms, 20Hz.

I wouldn't compare it to modern computer, ENIAC was the first Turing complete machine and I think that could do 500 to 5000 calculations per second depending on what you were asking it to do.

If you want to get up to Apple 2, then you're going to need to beef up your bus!

Hope that's helpful.

* From what I can remember, I studied this back in 1998!

[Onix]

[kumakami]