The 3100B ADRET synthesizer is a digitally controlled signal generator which delivers all 0.01 Hz to 200 kHz frequencies with 0.01 Hz resolution. The synthesized frequency can be either manually dialled through eight rotary switches on the front panel of the instrument (Local mode), or programmed in parallel BCD code through TTL signals sent to the programming connector on the rear panel of the instrument (Remote mode). Two channels A and B simultaneously deliver two output signals in phase quadrature with 5 n or 50 a impedance and an electromotive force adjustable from 0 to 10 Vpeak. Moreover, the signal delivered by channel A can have the following forms : sine wave, positivd square wave, symmetrical square wave, negative square wave, TTL level square wave. According to the user's needs, the 3100B generator synthesizer can be fitted with the following options : - Option 311IB : progranmable attenuator This option allows to attenuate one of the output signals of the generator synthesizer from 0 dB to 79.9 dB with 0.1 dB resolution. The attenuation value can be either manually dialled through three rotary switches in Local mode, or programmed in parallel BCD code through TTL signals in Remote mode. - Option 3112B : programmable phase-shifter This option delivers a sinusoidal signal phase-shifted from 0° to 359.9° with regard to the signal of channel A of the 3100B generator synthesizer. The phase-shift value can be either manually dialled through four thumble wheel switches in Local mode, or programmed in parallel BCD code through TTL signals in Remote mode. The electromotive force of the phase-shifted signal is adjustable from 0 to 10 Vpeak with 5 ft or 50 ft output impedance. - Option 3114B : Search and Sweep This option allows progressive frequency variation of the generator synthesizer output signals. Four modes of operation are possible depending on the function required : - Search function - Free-run Sweep - Triggered Sweep - Search or Sweep by external signal In all cases, twenty-one "birdy" or rectified markers display the frequency variation achieved.