Speaker output reflex receiver (T1653E)

Found in a 1924 publication, this 2-valve receiver has a speaker output. Power comes from several batteries. Information about the coils is given.

| Clique na imagem para ampliar |

Vibration Sensor LM10 (CB14310E)
The integrated circuit used in this project is unusual. However, we can take advantage of the...
Residential Alarm (CB17984E)
This alarm, found in a 2002 documentation, uses several sensors and has a 12 V supply, not...
Field Strength Meter (CB13667E)
This instrument was found in a publication for radio amateurs in 1973. The tuned circuit consists of...