多功能函数信号发生器，频率计，可产生三角波，方波，正炫波，锯此波，且波形幅度和频率可步进调节，最高频率可达40MHz-Multi-function signal generator, frequency counter, can generate the triangular wave, square wave, is hyun waves, saw this wave, and wave amplitude and frequency adjustment can be stepper, th