Like the recased Mac Plus by Techmatics, this Mac 512k has been re-engineered by Systematics General Corporation to meet TEMPEST standards. Unlike the Techmatics unit, Systematics chose to leave the Mac in its original case. While Techmatics changed the case, but left the actual Macintosh untouched, Systematics did the opposite, removing connectors and changing switches.
Front of the machine. Nothing unusual except for the square slot cutout where the keyboard RJ14 connector used to be.
Back of the machine. The brightness nob, power switch, and power cable have all been replaced with componets meeting TEMPEST standards. Also note that many of the ports have been removed, particularly that for the floppy drive.
The backside label. The manufacturer (or rather re-manufacturer) is Systematics General Corporation of Sterling,Virginia (a wholly owned subsidiary of Atlantic Research Corporation).
Guess what? That slot is another Sony 3.5" floppy that has been installed internally. The slot has been manually cut out.
A close-up of the keyboard connector. It attaches to the unit via the modular plug. Then the panel screws on to the front of the machine. The duct tape looking piece of material is a metallic mesh that prevents leakage of emissions. Note the brass gasket attaching the shielded cable to the keyboard housing. The metal box on the back covers the old keyboard connector.
More information is available at The Complete, Unofficial TEMPEST Information Page.
This Systematics T5170-2 belongs Sellam Ismail, who kindly provided the pictures and information used on this page. Sellam runs the Vintage Computer Festival in California.