Zhengzhou, where the function signal generator? Product parameters is it? How about quality? Phone? Zhengzhou Megumi Instrument Co., Ltd. specializing in various signal source, signal generator, function signal generator, original authentic, quality assurance, and perfect after-sales service! 0371-66227105 Features: 1, the frequency of 0.1Hz to 2MHz optional. 2, the output waveform: sine, triangle, square, ramp, positive or negative pulse wave, sawtooth, TTL / CMOS OUTPUT synchronization output, distortion 10Hz to 100KHz, less than 1%, the frequency response 0.1Hz to 100kHz, is not greater than ± 0.5dB Frequency Counter 1Hz to 30MHz main parameters: Model: LW-1641 Frequency: 0.1Hz to 2MHz Output Impedance: 50 ohms ± 10% Amplitude: not less than 20Vp-p (no load 90:10 to 10:90 square wave front of) DC voltage: ± 10V continuously adjustable symmetrical: