Precision Current Source (CB21052E)

Found in National Semiconductor documentation from the 1990s, this circuit employs basic components from the time.

| Clique na imagem para ampliar |

Continuity Tester (CB21394E)
Found in a 1967 Electronics World, this circuit uses components from the time. Modern...
Open Collector TTL Gate (CB24884E)
This is a discrete equivalent version of an open collector TTL gate. What we have is an inverter...
Crystal test (CB7536E)
This circuit was found in a 73 magazine for radio amateurs of the 90s. The circuit uses two types...