Photometer for enlarger (CB8342E)

This circuit for old photo enlargers was found in a 1970s RCA manual. The components are from the time, but modern equivalents can be used.

| Clique na imagem para ampliar |

Voltage Follower LM308 (CB4491E)
Other operational amplifiers can be used on this unit gain amplifier. The circuit is from the 1993...
Phase Shift Oscillator (MSB039B)
In this oscillator a phase shift network formed by C1, C2, C3 and R1, R3, R4 determine the fase...
Gain 100 buffer (CB9558E)
This basic buffer circuit can be implemented with other operational amplifiers. The circuit is...