Address decoder using the 74LS138 (CB20537E)

This decoder circuit 3 of 8 was found in a publication for PCs from 1992. The circuits are TTL and must be powered with 5 V.

Redisparable Monostable with the 4047 (CB11444E)
A positive transition in the trigger makes the outputs change state and remain so for the time...
5 Condition Indicator (CB6677E)
Found in an old publication about neon lamps this circuit works directly connected to the power...
5 A Current Boost (CB14533E)
This suggested application of the integrated 78xx voltage regulators is from one of the many...