Institute Newton C. Braga

27 MHz Wireless Microphone (CB13164E)
This circuit is from an American publication from 1970. It uses a coal microphone, which is...
Intercom (CB22488E)
This two-station intercom was found in documentation from 1966. R4 should be experimentally...
Frequency Indicator (CB6342E) This simple circuit was found in an Exar publication from the 1970s. The circuit makes use of the 567 PLL indicating when the signals are in the indicated frequency range. a hre
Frequency Indicator (CB6342E) This simple circuit was found in an Exar publication from the 1970s....