01/20/2002: First edition of page. >>>

apple m4120:

Apple M4120 Interactive Cable TV Box

quick facts

Overview Photograph
Apple IIc+ Front
Apple IIc+ rear view
Apple IIc+ rear view
FCC ID Does not have FCC approval.
Model or Part # M4120.
My unit's vintage Probably 1995 or 1996.
CPU 68LC040.
Memory 8Mb RAM.
Operating System Proprietary.
Ports NTSC and stereo audio on RCA jacks, Mac serial, S-video, RF in and out, Ethernet, ADB, SCSI, proprietary expansion slot, unpopulated floppy drive connector (for Mac type floppy drive), dual SCART. In the US version, the SCART jacks are covered with breakout panels labeled "DO NOT REMOVE".
Video/audio output Unknown.
Available peripherals Can probably use most "vintage" Macintosh peripherals. The HDI-50 SCSI connector is the same SCSI interface used on PowerBooks.

This piece of hardware is included just by way of commentary; it was not strictly part of my collection, and in fact I no longer own the unit I photographed above. This item was part of Apple's entry into the digital interactive cable/satellite TV market, and was developed in conjunction with British Telecom circa 1995. The hardware was deployed in trials in limited areas of Europe and the United States, and it went through several phases, of which the unit I owned was the "final" version. The very first units were demonstrated in off-the-shelf steel prototype boxes. Those early units had floppy drives and their boot OS was on flash memory. There were several intermediate versions, and then the final version illustrated above, which has a production-quality injection-molded housing, boot software on mass-produced mask-ROM and no floppy drive. (It's possible to bolt a floppy drive on; space for the connector is still present on the mainboard, though the connector itself is not fitted). In the recent past (probably mid-2001), a small explosion of these units arrived on the secondhand market, presumably due to a desperate cable provider clearing its closet for some spare cash, and you will see these units pop up on ebay from time to time.

The hardware platform is basically an off-the-shelf 68k "pizza box" Macintosh, probably an LC, with some tuner hardware and an MPEG decoder DSP bolted on (that's the chip next to the big heatsink in the picture above); I'm unclear on its capabilities, but I believe it's MPEG-1 only. There is 4Mb RAM soldered to the mainboard, and a 72-pin SIMM socket which in my unit was populated with a 4Mb SIMM. There is also a DIMM socket containing the operating system, and a proprietary expansion slot which is in all probability closely related to the PDS slot on Macs of comparable vintage, but it uses a special proprietary connector. Note that the casing is actually matte black; the reason it appears silvery is because of flare on my digital camera.

To date, I have not been able to find anyone who has successfully powered up one of these liquidated units. This might be due to dead PRAM batteries, or it might be because the remote control is required, or it might be because the unit doesn't power up fully until it detects a digital cable signal on the RF input. The furthest I got with mine was to plug it in, switch on the rear power switch (which only switches on the power supply module) and see the fan spinning. There was a quick glitch on the NTSC jack when I switched on, but no picture. Pressing the power button did nothing.

I have read a British Telecom white paper talking about this device, which states that it downloads most of its operating software (really, middleware) off the network, so the last theory above seems fairly likely to me. But it might be possible to put, say, an LC's ROMs in the unit and make it into a TV-output Mac; it's hard to tell how much hacking would be involved. Besides, most of the spare classic Mac ROMs in the world probably wound up inside A-Max emulator cartridges ;)


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