Elenco Electronics EP-130, Руководство пользователя

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Now that you’ve built and learned about the NAND
(inverted AND) circuit, it’s easy to determine what
the NOR (inverted OR) circuit does. The display
shows L when either terminal A or B is connected to
terminal H (119). The circuit output is high only
when both A and B receive low inputs. This is the
opposite of the OR circuit. The logic symbol for the
NOR circuit is shown with the schematic. The
function is written as A + B. The + symbolizes the
OR circuit and the bar over the symbol indicates the
circuit is inverted.
When you connect either A or B (or both) to terminal
H, the NPN transistor turns on, completing the
current path for the LED. When you connect both A
and B to L, the transistor turns off and LED goes off.
Notes:
EXPERIMENT #31: TRANSISTOR “NOR” CIRCUIT WITH LED DISPLAY
Wiring Sequence:
o
18-19-20-119
o
25-47
o
46-82-84
o
48-124
o
81-(to 119 “HIGH” or 124 “LOW”)
o
83-(to 119 “HIGH” or 124 “LOW”)
o
121-122
Schematic