森林斧子怎么做:谁能帮着翻译下面这篇文章?

Sweep appearance call frequency characteristic tester too frequently , use measurement for a the characteristic and characteristic frequently of phase frequently to examine the network, it is the commonly used electron that measures the apparatus . A traditional one sweep the appearance costs an arm and a leg frequently , can't receive the characteristic frequently of the looks directly while being analog, let alone the frequency of printing network responds the curve, give and use bringing a great deal of inconvenience. For this reason , have designed and swept the appearance frequently digitally.
This text has recommended being based on PLL to sweep the design method of the appearance frequently. In the design, sweep the signal source adopts and integrates and surrounds the frequency synthesizer MC145151 chip frequently, time select , separate cycle wave filter LPF and voltage-controlled oscillator VCO come on , realize. Sweep appearance regard one-chip computer 89C51 as core of controlling frequently , realize , sweep frequency walk into , change frequently originally in addition; The keyboard uses the ranks to scan and does not encode the way keyboard , realize through IO mouth expanding the one-chip computer; Adopt liquid crystal reveal circuit come , realize frequency count apparent , examine into network pieces of characteristic frequently and looks the number of the characteristic is apparent frequently. Having designed and basically reached digitization, the cost is not high, if need can also set up and print the circuit of interface , print the curve of characteristic out, more traditional simulation is swept frequently the appearance has facilitated much more.