Dude you just hit it out of the freaking park. That is the most concise explanation of the 400/800KB drive I have read. Even the biography is an excellent source of information. …

Anders, That's a very generous offer - and I may very well take you up on it. I'll see about buying the caps off Trag first though. It's be nice to get my SE/30's going again - e…

I've bought mine off Trag (Jeff) here on 68kmla. Prompt shipping, and a fair price (15us$ I think). I live in Denmark, and I'd like to volunteer my labour to a fellow enthusiast. …

I have a pair of SE/30's, from the serial numbers one is Irish and the other is American, and I'd like to replace the capacitors on both. One did work occasionally, but now only s…

...Just one more thing to note... it looks like the Mac floppy drive *isn't* a completely dumb device. Look in your copy of "Inside Macintosh", the hardware section, and read the b…

My Arduino board arrived so I can start experimenting with the Microcontroller. I also share the concern that the memory is too small, but well just have to see what happens. My n…

If you are going to emulate the 400K drive itself, it is completely dumb. The IWM in a first generation Mac is exactly the same as the IWM in an Apple //c or an Apple II non-integ…

You can also patch Drive Setup, which is better than HD SC Setup, IMO. It's not very hard to do.

If you don't mind risking such a machine...your best bet would be a Mac II. Otherwise, you could gut an external Apple 3.5" drive for the adaptor board and connect it to an IWM-equ…

Apple prevented third-party drives by not allowing people to format drives that do not already have the Apple drivers on them. (Not sure if I said that accurately, but you get the…

Wow guys lots of great information here. This exactly what I hoped would happen. Development work has stalled as I expected because of the Thanksgiving holiday here in the US. I …

Okay. I've got a Power Macintosh 7500 (see signature) with a 68-pin Ultra 160 SCSI LVD/SE Adaptec controller card. The model number of the card is AHA-2940U2B. It says on a labe…

Larry Pina has a very clear procedure for doing this in his book Mac Classic & SE Repair and Upgrade Secrets. It was a very common upgrade at the time. Books can be found r…

It may be best to see if you can find somewhere to mount a standard computer fan and find one to suit. Click to expand... Larry Pina has a very clear procedure for doing this i…

Jameco, mouser, digikey would probably have them

That's called a squirrel cage fan. It's more common in industrial and automotive applications, and, as you have surmised, is not a common or readily available computer part. It m…

get a metric ruler, go from there, its one of 3-5 sizes Click to expand... It is approx. 70mm tall with a power lead running nearly the length of the analog board. From your p…

presumably the later drives change speed depending on which track they're on, so one should be able to do the same thing with an emulated version and not bother counting pulses. …

get a metric ruler, go from there, its one of 3-5 sizes

I've got an SE with a really noisy fan I'd like to replace. Unfortunately, the SE uses an odd paddlewheel style fan instead of the fans you typically find in systems since that ti…

presumably the later drives change speed depending on which track they're on, so one should be able to do the same thing with an emulated version and not bother counting pulses. …

2k, starting tomorrow I will be working with some old school 64k ram and the arduino on a non related project, to see how easy/bad it is If the mac is generating the pwm on the ea…

The PWM signal is well documented in Inside Macintosh and Apple Macintosh Family Hardware Reference. A PAL reads the disk-speed buffer in RAM and generates a PWM. However, the 800K…

If you are going to emulate the 400K drive itself, it is completely dumb. What it receives is encoded RLL data which goes thru an amplifier straight to the write head. To read, the…

Have you come across the Catweazel? Catweasel Disk Controller ISA Catweasel is a universal floppy disk controller that uses unmodified PC diskdrives. The Catweasel can read …