The WAVETEK Model 110 Function Generator and Model 111 Voltage Controlled Generator (VCG) are semi-precision sources of waveforms from servo to video frequencies. These units are extremely rugged, completely transistorized portable packages. They feature complete plug-in printed circuit board construction with interchangeable individually calibrated printed circuit boards utilizing silicon semiconductors throughout. The extremely clean and stable waveform signal from 0. 005 Hz to 1 MHz (Model 110) and 0.0015 Hz to 1 MHz (Model 111) make these generators highly versatile general purpose pieces of equipment for the laboratory or the field. The Models 110 and 111 are identical in size and performance except that the Model 111 offers VCG and the additional ramp function. Both Models feature a main output with function selector switch and amplitude attenuator. In addition, they offer simultaneous 5 volt peak to peak 50.n. outputs of sine, square and triangle waveforms; 1 volt, 10 nsec. rise and fall time square wave; and, -10 volt sync pulse. Frequency is controlled by an eight position range switch at 20:1 range, thus providing good overlap. All outputs may be shorted simultaneously and the generator will continue to oscillate internally with less than 0. 5% change in frequency. Voltage may be applied back into the generator so long as this voltage does not exceed the maximum output voltage. Up to ±50 volts may be applied to the VCG input without damage. The Model 111 features VCG voltage control of frequency by the internal frequency dial operating in parallel with the VCG input terminals. The generated frequency is the resultant sum of the VCG input voltage and the dial setting. Without an externally applied voltage, the dial governs and the generator operates like a Model 110. By adding a positive voltage to the input terminals, the frequency is increased; by adding a negative voltage to the input terminals, the frequency is decreased. The applied voltage may be either a d-c programming voltage or an a-c frequency modulating voltage. The modulation band width is 100 KHz (it is possible to have a higher modulation frequency than carrier frequency, with a resulting triangle wave that may look like a staircase). The frequency dial is a continuously variable quality composition potentiometer. An electronic frequency vernier is incorporated for extremely precise frequency adjustment. The vernier covers one minor dial division for one vernier rotation. In addition to sine, square and triangle, the Model 111 also offers ramp functions. The base line of this ramp signal is zero volts and the ramp duty cycle is 50 per cent. The ramp on the binding post is a positive ramp; the ramp on the BNC connector is a negative ramp.