... 3.w/AM FM function MCH DDS Function Generator, SM-4040 DDS Function Generator, 40MHz Freq., built-in frequency counter.Specifications: ... % (10mHz-10kHz)Control modeINT/EXT (External TTL level,F1:low-level,F2:high-level)Phase-shift keyingWaveformsine, squareFrequency range100μHz ... 100s ±1%Control modeINT/EXT(External TTL level,P1:low-level,P2:high-level)BurstWaveformsine,square,triangle,±Ramp,±Pulse,Rise ...