Here are a few more.
Sadly, a bunch of my links are dead now.
Gotta love this message. It conveys the feeling that this thing is for real.
A local jeweler designed what he called a "winky board" and sold it to thousands of TS owners. It provided an AGC for both the audio input and audio output as well as shaping circuits to eliminate noise from the signal. This little board actually made storing programs on cassettes reliable.
Ah ... memories!
EDIT: It was a Winky Board - There are references here:
EDIT: Two of them have the 16KB RAM expansion modules if the system is memory limited.
Also, does anyone have a cache? Looks like it couldn't cope with the traffic.
This design sounds very close to the arduino ethernet shield design. Wonder if they're doing TCP offload and all that in the wiznet. If you buy a $20 or whatever '811 and attach the correct wires to the correct ports and provide 3.3 volts that basically IS the $50 arduino shield so this is pretty well trodden ground.
The wiznet stuff can be advanced enough that you're kinda stretching the truth by describing it as being on the internet. All the "on the internet" stuff is being done by a microcontroller and the speccy is just talking to another SPI device.
At one point I had a SBC6120 PDP-8 "on the internet" but not really. The PDP-8 thought it was talking to a serial terminal, that's all that was done on the PDP-8 / OS-8 side to be "on the net". There are plenty of little $100 boxes that terminate an ethernet connected telnet session on one side of the box and speak plain ole RS-232 serial on the other side of the box and that was what I was using and the speccy thing sounds about the same except terminating port 80 connections. Its not like putting windows 3.0 "on the net" using all kinds of device drivers and stuff deep in the innards of the OS.
Maybe "internet accessible" is a better phrase.
Its still a cool project aside from terminology. I'm sorta on and off trying to hook a wiznet module to what amounts to a modern S100 CP/M box as my slow ongoing retro experiment. Why? Because I can.