Join us as we live the time traveler's dream. Just in time for its 30th anniversary, the iFixit team laid hands on a 1984 original: the Macintosh 128K. And, you guessed it -- they opened it right up, so we can take a look inside.
The original Mac, released as the Apple Macintosh, retailed for $2,495 -- that's $5,594.11 in today's dollars. So what did you get for all that coin? Click on the 1984 Mac below for the slideshow.
The original boasted:
8 MHz Motorola 68000 processor
128 KB DRAM
Nine-inch black-and-white CRT display running at 512 x 342 (72 dpi)
400 KB total storage via a single-sided 3.5-inch floppy disk drive
My first personal computer was a 128k Mac bought shortly after the 512K Mac came out. The price dropped to $1,650 so it became a practical, home appliance. But PCs were advertised for $1,450.
After writing up the PC with a mouse, the salesman asked,"Do you want a monitor and keyboard?" that brought the PC price $1,750. I bought the 128K Mac the next day and our Macs have been bought in the 'fire sale' after the latest Mac models come out.
The M68000 had a unified, 24-bit address space, versus the segmented memory of the PC chips that used a linker trick, 'overlayed memory.' The M68000 had 32-bit registers and math versus the 16-bit Intel chip. Today virtual memory gives a unified address space hiding memory pages.
I could not afford the RS-232 driven, dot-matrix printer so I got the printer handbook with the codes. I wrote a printer emulator on my work VAX and simply printed Mac graphics into bit-mapped files, which printed on the VAX dot matrix printer and VT-series terminals. This upgraded my career beyond operating system programmer.
Eventually we sold our 128k Mac for $200. Over the years, I had cleaned the lint out of the mouse encoders and once replace a soldered-in, fuse. Apple had an unusual fondness for soldered in fuses.
I'm typing this note on a G4 PowerBook resting on top of a G3 PowerBook. The network connection is via a MacBook (Intel) because WiFi is no longer compatible with the G4. Macs have legs and a long life that often outlasts peripheral technologies.
Hi Alex, I used to repair TV's for a living. The early mostly valve colour TV's used to generate a no load ~40kV because the circuits were fairly high resistance. There was a triode wired in parallel with the CRT that was fed a signal that was effectively the inverse of the magnitude of the average beam current (around 5mA peak) so that the image size wouldn't change as the brightnes changed (and with it the EHT).It also prevented the EHT from getting high enough to produce X-Rays.
This stabilised the EHT to around 27.5kV deemed to be the highest save voltage that wouldn't produce significant X-Rays. If you turned the brightness right down in a darkened room you could see the anode plate glow red because it was effectively 27.5kV x 5mA = 137W disipated in around 3"sq. It was a rough and ready way to regulate such a high voltage.
When they switched to silicon rectifiers which have a much lower impedance and transistor or SCR horizontal deflection circuits, this load triode became unnecessary.
To my knowledge there is no commercial CRT out there that has higher than 27.5kV EHT. It would need significant lead shielding.
Monochrome TV's used to have only about 18kV EHT and didn't need output regulation due to lower beam currents.
As to discharge of the EHT when working on them, we used 2 screwdrivers crossed and it had to be done several times because of the impedance of the capacitor plates (formed by the graphite outer coating and whatever material was used to line the interior. We just kept crossing them until the crackling stopped.
A colleague of mine showed me that if you hold the 27.5kV cap when the TV is off and then turn on the set you can be charged up to that voltage without discomfort as long as you were wearing good insulated sold shoes and kept clear of earth.
I agreed with his theory, but always considered to much could go wrong like having a pinhole in your shoes and having sweat get into it etc. so I never recommended it to anyone as a dare and never tried it.
The focus voltage on a colour TV was also in the vicinity of 5kV and I got belted by that badly enough to have a 1mm hole burned into my finger that took a year or so to heal properly. The current was never enough to cause VF (it was DC also) but the power disipated could effect significant burns.
In years gone by I've tinkered with televisions and also designed CRT-based displays before LCDs took over. It's sad that part of my design knowledge is redundant but I don't miss the weight of the big CRTs.
Anyway, for the benefit of those youngsters who don't know about them, yes they run at anything from 12kV to 30kV. Even quite small colour CRTs often run at 24kV. So if you do dismantle anything with a CRT in it which has been switched off for less than a week, then be careful. Some designs include a high value resistor which discharges the EHT, but some don't. As I've found a few times over the years, there's not enough energy there to kill you, but enough to give you a nasty jolt even after it's been off for an hour.
An Internet search should tell you how to safely discharge your CRT. Happy dismantling and may you not have too many screws left over.
Prices for a 128K Mac range all over the place, Chuck. I didn't keep my upgraded machine because it was worth less than $10 a few years back. Looks like I should have though: now they're old enough to be worth some money again, at least judging by prices on ebay.
I had a Compaq luggable that I saved for years and just sold for a couple hundred dollars. For those who don't recall, the machine was an IBM compatible in a box that looked like a suitcase, or really, more like a sewing machine (for those that remember those). The keyboard was detachable and formed the bottom of the suitcase. When you removed the keyboard this exposed the front of the machine that held two standard, full height, 5 1/4" floppies and a 9" green screen. The motherboard, cards and drives were standard PC fair, and you could load all the regular PC cards into the aluminum chassis. The construction of the machine was really admirable, and had a lightweight aluminum framework that was quite similar to an aircraft. At 28 Lbs, it was the first laptop – sort of.
It was a fun machine to have, and at one point I even mounted a hard drive to run GEOS, but with an 8 bit bus on an XT motherboard, that hard drive wasn't much faster than the floppies.
AnandY, millions of people wondered why Motorola blew it like that. They supplied Apple's processors for a long time, until the PPC, when IBM took over, if my memory serves. Then with OSX came Intel. Mot eventually spun off its semiconductor division, the processor part of which became Freescale.