New Highsensitivity Electrometer

Coupled Cathode Follower

New Dial Brings New Convenience to Octave-Band Noise Measurements S . The new Type 1230-A D-C Amplifier and Electrometer is basically a high-resistance millivoltmeter. Voltage, current, and resistance is indicated on a panel meter and can also be indicated on a recorder. Because of its high sensitivity and excellent stability, this instrument has a wide range of applications in science, engineering, and industry. Typical examples include the measurement of Ionization currents, photo currents,...

Frequency Audio Generator

The Sound Apparatus Company, Stirling, New Jersey, has recently completed the development of its Model SL-4 Recorder. It is designed for the plotting of frequency response curves of electro-acoustical apparatus. With it, response curves of loud-speakers, microphones, filters, equalizers, transformers can be automatically plotted in a very short time. A General Radio Type 1304-B Beat-Frequency Audio Generator is especially recommended by the manufacturer as the generator for driving the...