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2. Dirk's Tinkering Lesson... (by Dirk Wenk)

Or: How to fit a Silversurfer and an Express-Adapter into a Desktop A1200

[Attention: If you dare execute the actions specified hereafter, you do it at your own risk!]

Why do without of all those nice extras because you do not have a tower?

This or similar (well, it was more the lack of money) I asked myself, when I wanted to smarten up my A1200 a bit.

When I had bought my used A1200 it was fitted with a Blizzard 1230/50 and the SCSI-Kit. By the way, it was that model manufactured in Escom times and therefore had the so called "Escom-Bug": the floppy-disk drive installed does not forward the "Drive_Ready" signal. This prompted my first modification on this Amiga.

There are many instructions explaining this procedure on the Aminet and some of them are really hair-raising! They start from the installation of a capacitor and lead to a complex timer circuitry emulating the signal. Not quite usable if you consider that the drive gets that signal, it just isn't forwarded. Fortunately somewhere there is the "correct" instruction.

Actually you don't need to do anything else but tap off the signal from the floppy board and lead it to the motherboard. Since I did that, all the old games absolutely wanting this signal run again. Unfortunately now the drive is connected solidly, that is permanently, to the motherboard. But main thing is, it works!

When I networked my A1200 via PCMCIA network board, another modification was necessary. The A1200 has difficulties with the reset signal at the PCMCIA bus, and again I had to look on the Aminet for the different solutions. The most simple was to solder a 10-µF-capacitor into the reset line. And it worked like a charm!

And some time later the space on my harddisk became tight and quite conveniently I obtained a 4GB 2.5" harddisk of the brand "Toshiba". Unfortunately the speed of data transfer was only slightly higher than before and formatting took accordingly a long time...

At about the same time I wanted to use my A1200 as a modem server. But the serial interface installed originally isn't of the fast type, not to mention the CPU load. So I bought a Silversurfer.

The installation started, and proved quite perverse. I could not imagine why this module had to be installed turned this way but not the other, well fitting, way, so I began using metres of adhesive tape, because the module nudged here and there and could have caused more than one short. After cutting the appropriate opening for the serial connector into the housing with drill and saw, everything was nicely reassembled again.

Recently I decided that the harddisk really was too slow, and I purchased the IDE-fix device with the suggestive name "EXPRESS Bundle". Before the installation I was convinced it would fit into the desktop computer... well now...

Open the computer, press the Express adapter onto the chip and, aaeeh... rubbish, the adapter doesn't completely contact the chip, because very close to it I had soldered the capacitor for the PCMCIA fix. And of course the adapter touches it. But no problem for me, a bit of solder here, a cable there and it fits! Screen metal over it and ... Oh oh! The sheet metal touches slightly and the harddisk clamp does not fit any more, because the opening is covered by the board! Had they arranged the Express connectors at the board differently, everything would have been ok!

So what else to do, but bend the sheet metal of the harddisk clamp? Twisted through nearly 150°, but now it fits. And the keyboard should hold it down. Finally connect the quadruple adapter with the Express adapter with help of the ribbon cable and somehow stabilize all of it. What seems nearly impossible, because of that ridiculously short cable, eventually works. Close the computer, switch it on and ...Nothing...mmmh.

Again open the computer and lo: The pressure of the keyboard was too great! The bent harddisk clamp pressed together with the keyboard on the connector of the Express adapter and levered it off the chip. And I notice that the case could produce a short circuit. Another wodge of adhesive tape! All right, I need something to avoid that levering off of the adapter. I catch sight of a big rubber ring from an old "Competition Pro 5000" joystick in my spare parts box, just the thing to put on the side of the adapter board. The housing presses at the left and the rubber ring at the opposite side down on the board...can't go wrong, I believe.

Ok! All this sounds really adventurous and the housing is slightly bent (but this is almost unnoticeable), and the board suffers no harm by this. Shut the housing again. Computer on and running! But unfortunately not long, for after the SetPatch a fat Guru occurs.

But this trouble quickly is repaired, because together with SetPatch the NSD patch is started. And this seems not to go so well with IDE-fix. SetPatch is now run with NONSD and works. IDE-fix is set to "Pio3" mode and look, instead of 1.2MB/s the 2.5" disk makes 4.9MB/s!

Hey, this was well worth the effort, wasn't it? :)

Now I can't help thinking if this quadruple clockport extension has the room to install a sound module... then only a BPPC with suitable BVision would be missing :) But that certainly will not live happily with the Silversurfer...

Well, now I'd like to know the adventures you have experienced while updating your Amiga. Just write an article about it!

Dirk Wenk <wax@topmail.de>