4 MHz Sweep Function Generator with 5 digit Red LED Generates Sine, Triangle & Square waveforms from 0.5 Hz to 4 MHz 20Vpp output into open circuit (10 Vpp into 50 Ohms) TTL and CMOS Output <25 nS Voltage Control Frequency (VCF) input 100% DC offset Built-in 80 MHz, 5 digit frequency counter Variable amplitude output plus 20dB attenuator 1-Year WarrantyB&K Model 4003A is a 4 MHz Sweep Function Generators. The sweep function offers linear or log sweep with variable sweep rates and widths. The model 4003A has the addition of a 60 MHz five digit external frequency counter.