The 4003A is a 4 MHz sweep function generator that generates sine, triangle, and square waveforms from 0.5 Hz to 4 MHz with linear or logarithmic sweep capability and variable sweep rates from 5 s to 10 ms. It features 20 Vpp output into open circuit (10 Vpp into 50 O), ±10 V DC offset, a 20 dB attenuator, and TTL output with rise/fall times less than 90 ns. The model 4003A distinguishes itself with a 20 MHz 5-digit LED display frequency counter with 0.01 Hz resolution, CMOS variable level output (4 Vpp to 15 Vpp), and voltage-controlled frequency (VCF) input for 0 to 10 V control. These features make the 4003A ideal for laboratory testing, signal generation, frequency measurement, and circuit development applications requiring both precise waveform generation and external frequency monitoring capabilities.