my so-called blog (redux)

I actually remembered to take the VT home this weekend. I opened it up and spent some time trying to figure out what to do with the innards; one of the things about CRTs is that the picture tube itself actually holds quite a bit of charge in it - this being a 12″ screen, we’re talking about 13kV, or thereabouts. Normally, you go about discharging the tube itself and take the thing apart. This is the normal route but I didn’t have anyone at the time to assist in this maneuver - it’s nice to have someone to call for help if you screw up - and I got impatient.

The VT320 is actually put together in a somewhat interesting fashion, given that this is expensive electronics from about 21 years ago. Most everything snaps into place. There’s really only about six screws in the thing total that matter - two remove the case and four more hold the CRT in place. I managed to find the service guide for the unit, and set off taking the PSU out. I removed the CRT and the main logic board as one piece. The case itself is three parts - the front bezel, the bottom tray and the back, and the bottom tray is held to the bezel by snaps (the back comes off), so I could just unsnap the bottom tray for leverage and undo the few snaps that attached the logic board to the tray. Then, four screws and some careful lifting and I had the thing in pieces.

Next, I went ahead and roughed-in the screen. I ran into two problems here - the bottom of the case has a nice foot that allows you to adjust the tilt of the screen. It’s got a pretty powerful spring in it to accomplish this, and, needless to say, iBook innards are much lighter than a full-out CRT and all the associated circuitry that comes with. I’m going to have to figure out a way to get the unit weighted down in the back.

The other problem I had was with the screen. While the LCD itself fit pretty well in there, the CRT screw mounts got in the way, so I ended up totally disassembling the screen. I got it down to pretty much just the panel, and took off the frame that includes the AirPort antennas, a reed switch (so it knows when you close the lid), the inverter and the microphone. With all of that stuff removed, the screen fit in fine. It’s in right now with packing tape.

So, once I got the screen in, I started working on the logic board. For now, I pretty much just dropped it in the bottom of the case. I ran the power switch out the side and taped the speakers down to the grilles in the bottom of the case. I ran a spare iMate into the old contrast wheely thing and into a USB port - with it all assembled, I really don’t have much room for USB devices and whatnot in there.

With all that done, I went ahead and hooked it into power and hit the switch for the first time. Lo and behold, nothing happened. Such a pain in the ass. I tore into it a bit and realized I had loosened one of the cables on the inverter board; a reseat and it was on its way.

So, now I’ve got this thing mostly mounted. I put the back of the case back on, and, apart from the fact that you really can’t see inside to see otherwise, it’s pretty much done. There’s still some to do - I’m waiting on the new battery for the system, I still need to get the new HDD and RAM, the combo drive needs to go back in, and I’d like to mount things a bit more nicely - but it works, and I’m actually using it to type this entry up.

Speaking of remounting things, right now I have the motherboard installed without the magnesium frame it sits in. This is kinda problematic for some things - the hard drive isn’t latched down (ah, the magic of tape!) and the CPU heatsink isn’t really attached to anything. I think I might experiment with the Dremel to see if I can make the frame work and have the board mounted back to the back of the screen. I can use the rest of the case for weights, and maybe a power strip and a couple of nice hubs. It’d also be nice if I could get some of the ports worked out differently, so that they sit more-or-less where the former serial ports and whatnot sit. And, a real power switch. It’s absurdly hard to find a beige or grey momentary on/off switch - I’m going to end up building a circuit to deal with that.

All in all, I think I’m at about 50%. A little hot glue and it’ll be done!

So I figured, new year, nice introspective blog post about the past year. But then, I thought, let’s cut up a bunch of computers instead! So much more fun.

I managed to get ahold of an old Digital VT320 terminal. They’re pretty neat gadgets but not horribly useful nowadays - they have a screen resolution of 80×25 or 132×25 (it’s software switchable) and connect via serial to the host using three-pair cable terminated in DEC MMJ plugs. Originally, I was just going to hook it into a normal computer and use it as a separate screen for the novelty of it, but it turns out it’s very hard to find MMJ plugs nowadays.

So, a plan B was hatched. The screen on the VT320 is 12″ diagonal, which was a pretty popular size for small laptops before the whole widescreen fetish began. I figured it wouldn’t be too hard to grab a machine about that size and mount it into the terminal, making a sort-of miniature iMac sort of machine. And, since I evidently have nothing better to do with my time ever, I went ahead and sourced a 12″ iBook G4 to use.

The iBook G4 I have is a 12″ model running at 1.07GHz. It’s got a 30GB disk, combo drive, 512MB RAM and an AirPort Extreme card in it. I set off tonight getting the machine taken apart and kinda roughly reassembling it in a way that would make it into a desktop machine. I pretty much have an iBook G4 tablet now - for the first stab at it, I pretty much just took the machine and flipped the screen around backwards. I think this is essentially how I’m going to have it though I might ditch the frame around the motherboard and rearrange some of the cards instead - certain things like the USB/etc. ports and the DC-In board are situated so things tend to stick out of the sides too much. I also need to find a cheap USB hub to mount inside the enclosure as well, so I can have built-in BlueTooth and whatnot. I’m also thinking about mounting my spare iMate ADB-to-USB adapter in the finished product, just to keep the retro going.

I was actually considering mounting a standard 3.5″ hard drive connected to a FireWire bridge board inside the case. I’m kinda rethinking this plan now, though - it turns out the battery that came with the iBook was one of the recall ones, so I could mount the battery inside the machine somehow and end up with a battery-powered desktop. I definitely want to get a bigger hard drive for it, though, and upgrade the RAM to 1GB. I was also thinking about mounting a webcam in the system, but that’ll depend on how much clearance I end up having in there.