.. 3.9

Logic gates
===========

**Objective**

Study of logic gates using SQ1 and PV1 as inputs, using TTL logic ICs
7408 and 7432.

**Procedure**

.. image:: schematics/logic-gates.svg
	   :width: 300px

-  Enable A1, A2 ands A3. Set input range on A1 and A2 to 8V
-  Set SQ1 to 200 Hz and adjust timebase to view several cycles
-  Select SQ2 from the WG wave shape, set WG to 200 Hz
-  Repeat using the OR gate, 7432
-  The 1k resistor is required to give the 5 volt signal to A3 input

**Discussion**

The working of the logic gate will be evident from the 3 waveforms. You
may shift traces vertically to separate them for clarity.
