Logic lab hardware consists of the mainframe, an assortment of 32 integrated circuits, pre-stripped
wires for circuit interconnection, four fully decoded LED numeric indicators, an IC extractor, the removable breadboard, and the three IC troubleshooters—probe, pulser, and clip.
The mainframe is made of polycarbonate foam with rounded corners and a 15° canted front panel for ease of use. The cover is attached to the mainframe under-body with just four screws, and when the cover is removed all circuit components are easily accessible for checkout and servicing.
The breadboard is held in place by two magnetic strips, making it easily removable by pressing on the bottom edge. Thus several students can use the same mainframe, or a single user can build several circuits simultaneously using the same mainframe.
Integrated circuits and interconnecting wires are pushed into the breadboard connection points: no soldering is necessary.
Four buffered light-emitting diodes (LED's) are located on the front panel above the breadboard. These act as indicators for circuits installed in the breadboard. Also, six "bounceless" switches provide clean steps without false switching caused by contact bounce.
Inside, the mainframe contains a five-volt, one-ampere power supply and clock generators at two frequencies: 1 Hz and 100 kHz. The TTL compatible circuits in the mainframe are all fully short-circuit protected.
Two rear-panel connectors provide five-volt power for the logic probe and the logic pulser. The logic probe's indicator lamp shows the instantaneous logic state of any point in a circuit: it is off for logic lows, bright for logic highs, and dim for bad levels. Fast pulses are stretched and displayed at 10 Hz. The logic pulser drives any circuit node to its opposite state when the button on its body is pressed. Together the pulser and probe provide a stimulus-response test capability that is helpful in building circuits, troubleshooting, and learning how digital circuits work. The logic clip lets a student see the logic states of all pins of 14-pin or 16-pin TTL circuits at the same time, a valuable aid to comprehension.
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