Posts tagged with “old macs”

The Dome

A couple of weeks ago I found a very reasonably priced iMac G4 being sold locally, and having always been somewhat interested in them (and having never had one before) I decided to get in touch with the seller and go pick it up. What I ended up getting was a fantastic condition first generation iMac G4/800. It has a few minor scuffs and marks on it here and there, but nothing a couple of alcohol wipes couldn't take care of.

What has kept me away from iMac G4s in the past has been the fact that, by and large, they are OS X only machines. I have very little interest in PPC OS X as it largely still feels too new to be "retro" and yet is too slow and incompatible to be used for much. I tinker with it from time to time, but System 7 and Mac OS 8 and 9 are where most of my interest lies. Only the first revision of the first generation of iMac G4 could run 9, and even then only it's special version of 9.2.2 (which is not hard to find), but that is good enough for me. I decided to take a gamble on this particular machine because 1) it was very cheap, 2) it looked to be in good condition, and 3) it was a 15", and all of the first gen iMac G4s were 15", so there was a chance that this one was a first gen. Reading the service manual I also learned that not only is the first gen the only generation to be able to boot natively into 9, but only machines with serial numbers less than xx305xxxxxx will as well. This machine is in the xx200 range, so it should boot 9 just fine. It's also the highest end first generation model sold - with the 800MHz CPU, 60GB HDD, and Superdrive. It was also factory upgraded to 512MB with a single PC133 DIMM, leaving the SO-DIMM slot vacant. The airport slot is also surprisingly empty, but that's not really a problem for me as I have little interest in WEP encrypted 802.11b.

Now, the bad news. Unfortunately this particular machine has screen issues. Particularly, the "white screen of death" that seems to be not entirely uncommon when researching these machines. This one in particular boots as one would normally expect when the power button is pressed - it chmes, the fan spins up, if an HDD or CD with OS loaded is present you can hear it begin to boot - but the screen is forever white. When it first kicks on the screen is more of a gray, in fact it's the same gray that you would expect for a machine of this era's first image (all of my G4s do it too) but instead of showing a happy mac, or the "OS not found" symbols, within a few seconds it transitions to a bright white. One way I know that the machine is booting is that I am able to enter open firmware and use commands to shut down, reboot, and eject the optical drive tray. This is good news, as it tells me that the motherboard works properly, and when I hear it booting from the HDD or optical drive I know that the IDE bus works as well.

I don't know which part is causing the problem, but I have been able to narrow it down to one of three things: the video connector on the motherboard (very unlikely), the video cable that runs from the board, up the neck, into the screen (somewhat likely, but I would expect flickering when the screen is articulated and wiggled), or it's the LCD panel itself - most likely, I believe, and frankly also probably the easiest to replace. The second easiest would be the logic board, but the video cable is contained within the neck itself, and getting a new neck with wiring harness so far seems rather difficult. I would also like to avoid replacing the logic board because there is little certainty that I would get another 800MHz first-gen board, which is what I very specifically want.

The Neck

Now, this machine does actually have video output. It's one of the few macs (along with a handful of iBooks, PowerBooks, and other iMac G4s and G5s) from the early 2000s to use "Mini VGA" which, aside from having a weird connector, is exactly what it sounds like. On this machine it doesn't allow for adding a second extended display - it can only mirror the primary display - but in this case that happens to be exactly what I want to do. Enough macs used Mini VGA that there are a plethora of the adapters available, and I was able to pick one up for about $4 shipped. So you may be able to see where I'm going here.

What I have chosen to do is remove the neck and screen assembly entirely, and what remains is what I have chosen to name "The Dome". The Dome is, obviously, the bottom half of an iMac G4 - a white plastic hemisphere driving an external monitor. It looks a bit strange, sure, like a mac mini about to pop, but it is a more compact G4 running OS9 than either the Quicksilver or Digital Audio, so that's a plus. And at 800MHz with 512MB RAM, it's no slouch either. Granted the GPU is fixed (GeForce2 with 32MB) but seeing as it's only ever driving 1024x768, that's not really an issue. No potential for a SATA card either, but I plan to at least get it upgraded with a 7.2k hard drive - the original superdrive will stay.

The process for removing the neck and screen is fairly trivial. Remove the bottom case, disconnect all the wires, and set it aside. Remove the drive carrier, power supply, and fan from the upper housing. The hardest part is removing the extraneous wires from the blind mate connector. This connector carriers a number of signals - power/sleep LED, microphone, display inverter voltages, fan, and speaker. Everything but the fan and speaker is in the display, so I removed those pins from the connector. The fan could be powered from the drives' molex connectors, and you could forgo a speaker, but I didn't want to do either. I also took this opportunity to clean out the fan and top of the case, as well as the peculiar two-part power supply. The neck is secured to the base with five screws, and once they are removed it pops straight off, and the various wires are fed through the hole left behind. I may 3D print something to cap this hole, but for the time being I am going to leave it as is.

As mentioned earlier, I do plan to upgrade the hard drive to a 7200RPM unit. The costs of PC133 SODIMMs are also so low right now that, at $8 shipped, there's really no good reason to not upgrade it to 1GB RAM. The fan is a standard 92mm PWM unit, so I plan to upgrade that to a Noctua as well. There's no real need for this - the included fan works just fine - but I would like something with greater airflow at lower speed. I would also like to find something that allows me to monitor the temperature and fan speed in OS9, though I don't know that such a utility exists. I have also noticed, in a couple of days of using it, that it is far more stable than my Digital Audio. This will require some further followup and investigation, and perhaps a future post.

Drakware ADB2USB

Not long ago a friend of mine (hey defor!) gave me a few APple ADB keyboards - specifically including an Apple Extended Keyboard (the I, not the II that is far more popular). It sat in a box for a bit until I was able to clean off enough desk space to actually use it on my old mac desk, but once I did I immediately remembered why I liked it so much. I'm not a mechanical keyboard enthusiast as some are, but I do really like the general feel of mechanical keyboards, and this one is no different. Years ago, with my first collection of mac stuff, I had one or two, but ended up getting rid of them like I got rid of most everything else when I had to move. Back then few people were interested in hanging on to such things, and as it was the market was flooded with them and there was little interesting, and the keyboards I had weren't particularly pretty specimens, but they were nice to type on.

Around the same time, mid to late 2000s, I started regularly visiting a the local university's surplus store. In addition to providing items for sale to the state's centralized action system, this university had its own small store that was operated out of one of the warehouses on the far edge of town. Twice a month, every other Thursday if I recall correctly, from 9am till noon, they ran a store where you could purchase anything from dorm furniture, to heavy equipment and tools, to computers and all sorts of miscellany. Cash only, and it was priced to move. Over the year or two I frequented that place I came home with all sorts of little goodies. Including, in one trip, about 30 Griffin iMate adapters. These were devices that would allow one to use ADB devices (keyboards, mice, dongles, various input devices, etc) on modern machines with USB ports. Someone had obviously recently found a stockpile of them in a closet and dumped them into surplus' hands, which then threw them in a giant bin of other cables and dongles priced at a mere twenty five cents each.

I don't know how many I came home with, but I think it was at least 30, and I wish I had continued to search for more - looking back. I also wish I had kept one or two for myself, as it was I either gave away or sold every single one I had. These days it is not uncommon for them to sell as high as $50 on ebay, and they usually get snapped up very quickly.

Thankfully there are other alternatives, one of the most popular being the Wombat, which, at $50 (plus $10) is a bit pricey for me even though it is a rather powerful device. By chance I happened across the Drakware ADB2USB, which is an incredibly tiny device, barely larger than the ADB connector itself. For $20 it comes with a very tidy 3D printed case. One side has an ADB socket, the other a Micro-USB socket, and then you plug it in and go.

I was thrilled when I found this thing, because 1) $20 shipped for such a device is exceedingly reasonable, and 2) we're currently in the process of preparing our house for sale, then moving, so all non-necessary computer hardware has been packed away, so there is no longer an opportunity for me to use the AEKI on old macs, even though I had grown quite fond of using it. This little adapter would allow me to continue to use this keyboard on my modern systems - really anything with a USB port. The creator has very generously provided a fantastic web tool for remapping the keys, something I find necessary in order to swap the command and option keys (or win and alt for windows) in order to use my alt and winkey shortcuts without going crazy. If I only used one keyboard I could probably get used to it, but as it is I'd rather just have things be as they should. Similarly I can (but have not yet) map some of the F-keys to media or volume keys, which would be rather handy. The new keymap can then be flashed to the adapter with a simple command line utility and is then instantly available - no need to even disconnect it or the keyboard.

I don't know that I will continue to use the AEKI forever, but simply knowing that I have the option is rather heartwarming. It feels nice to type on, it looks cool, and it was cost effective (while still supporting a member of the electronics entrepreneurial community). I have not tested it with anything other than the AEKI, but I understand it should work with all ADB keyboards. I believe mice are supported as well, but I don't know about tablets or other devices. I have emailed the creator and he is very responsive and friendly, so should you have any questions I would highly recommend reaching out - his contact info is in the webpage linked above, or you can simply search "Drakware ADB2USB".