Laptop Model 125

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The Outbound Laptop Model 125 was the first Macintosh portable clone sold by Outbound. It had a different form than Outbound's later notebooks, being more of a luggable at ~10 lbs with the camcorder battery installed.

The Model 125 supports System 6 and through 7.0.1. There are indications that 7.1 is supported, but that needs to be tested.

Notable features of the Model 125 included a detachable keyboard with integrated pointing device (isopoint), four additional SIMM sockets dedicated to a persistent Silicon Disk (RAM Disk), the ability to work in target mode as a SCSI device before the PowerBooks (requires optional SCSI interface), and the use of 2.5" IDE drives rather than SCSI drives.

Internally, the Model 125 supported either a floppy drive or an internal hard drive. The floppy drive was a notebook-PC style 1.44MB drive (Citizen UADO?) with an additional circuit board interface which provided support for Macintosh 800K disks. The internal hard drive options were 2.5" IDE hard drives and were typically Prairi-Tek models from 20MB to 80 MB, although Conner and Maxtor models were also known to work.

Technicians at Perfit stated that only certain capacities are supported (up to 80MB) but this has not been confirmed.

The Model 125 required that the ROM chips from either a Mac Plus or a Mac SE be installed on a socketed module and the module plugged into a SIMM socket inside the Model 125.

There are a total of nine SIMM sockets in the Model 125. The first (closest to the ports on the PCB) is the ROM socket. The next four support system RAM in the same capacities supported by a Plus or SE. The final four are dedicated to a persistent RAM disk which Outbound named the Silicon Disk and retains its contents as long as the Model 125 has power. There is also a small backup battery in the Model 125 to maintain the RAM Disk contents while the main battery is replaced. The backup battery is a fairly expensive camera battery and will drain quickly if the main battery is allowed to deplete its charge.

The Silicon Disk sockets officially support 256K - 4MB SIMMs in any combination for a capacity from 256KB up to 16MB of Silicon Disk storage. Sixteen megabyte SIMMs have not been tried in the slots.

The larger the Silicon Disk, the larger the drain on the main battery even when the machine is switched off. With a 16MB Silicon Disk installed and the Model 125 switched off, the main battery will be depleted in about 24 hours if external power is not provided. Shortly thereafter, the expensive backup battery will be depleted...

The Model 125 has two built-in Mini-DIN 8 serial ports, like the Mac SE's serial ports. They support LocalTalk.

There is no external SCSI port, but an expansion port can be connected to a SCSI option using the Model 125 cable. When using the SCSI option, up to seven external hard drive may be connected, or the Model 125 can be connected to another Macintosh in Target mode and it's internal disks treated as external disks for the other Macintosh. The Silicon disk may also be accessed in Target mode.

The expansion port could also be connected to an external floppy drive. The SCSI option and the external floppy drive cannot be used simultaneously. The external floppy drive was identical to the internal floppy drive, being a Citizen 1.44MB floppy mechanism built for PC notebooks with a circuit board that enabled 800K floppy disk operation.

The third use for the expansion port was to dock with the Mac Plus or Mac SE from which the ROMs were removed. This required that a docking card be installed in the ROMless machine. The connector for the Model 125 exited the host Macintosh through the lower right-hand ventilation slots when the docking card was installed. With the docking card installed and the Model 125 connected to its host, Outbound's literature claims that the ports, I/O devices, screen and RAM of the host machine is usable along with the Model 125's resources, although it notes that performance will be better if all but 512KB of RAM is installed in the Outbound.

The Model 125 expansion port and its special cable look like mini-centronic connectors but are actually built from Hirose DXM series connectors with 26 conductors. Both the SCSI option and the external floppy drive have an 85C30 serial interface chip as the first component after the cable enters the device, implying some sort of serial communications protocol.

There is one other expansion port next to the two serial ports and the Model 125 expansion port. This final port has the from factor of a VGA connector, but it is *not* a VGA connector. Connecting a VGA monitor to this port will destroy one of the rectifiers (reverse bias?) on the Model 125's analog/power supply board. The analog/power supply board is in the square metal can next to the battery compartment in the base of the Model 125.

This port which resembles a VGA port is reputed to be a digital display out port, meant to work in the same way as the Mac Portable's digital display out port. Outbound intended to market a video adapter for this port, but there's no evidence they ever actually produced it.

The Model 125 keyboard is styled to resemble the ADB keyboard which shipped with the Mac SE. It can be operated attached and locked to the base of the Model 125, or detached through an IR interface, or detached using a cable with RJ11 connectors at either end.

The keyboard has an Isopoint pointing device in front of the space bar which provides all of the functionality of a mouse. A mouse may also be attached, by plugging it into a port on the keyboard. The port supports the old Bus Mouse interface and the mice shipped by Outbound were Microsoft Bus Mice. The mouse interface is not ADB, nor PS2, nor serial.

The keyboard contains its own 3V lithium battery and if this battery is flat the Model 125 cannot be powered on. The unusual 3V keyboard battery may be replaced in size and voltage with a pair of 'N' size batteries in series.

OS support is provided by a special Outbound installer. After the unmodified Macintosh OS is installed to a disk drive, one boots from the Outbound installer disk and runs the installer application which loads Outbound specific control panels or DAs to the system disk, modifies the system files, and modifies the Model 125 EEPROM if necessary.

The Model 125 contains two 64Kbit EEPROMs which provide on-board storage for whatever Outbound needed to make their hardware work. The IDE hard drive parameters are known to be installed in there, as well as code to support either the internal floppy or hard drive depending on which is installed.

Some RAM SIMMs, perhaps those which draw too much power, can cause the Model 125 EEPROMs to become corrupted, causing the laptop to make a buzzing sound at power-on, display the Wallaby screen image and do nothing more. When this happens, the socketed EEPROM chips must be removed and reprogrammed. There is no way to boot the machine from this condition and run the installer program to reprogram the EEPROMs while they are still in the Model 125.

The Model 125 uses an 19V 1.5 amp (?) AC adapter. The AC power is rectified in the Model 125's internal power supply to charge the 12V battery and supply system power.