开通Ｎｏ．７信令后应注意的计费问题福建省邮电工程公司黄伟华某端局在测试开通之后，发现所有公用电话拨打长途电话均无反极信号，拨打本地网用户有反极信号．查用户数据，这些公用电话均有反极性能＜ＨＭ＝ＰＯＬＡＲ＞．由于拨打本地网用户也有反极信号，因此怀疑问... Open No. 7 signaling should pay attention to billing problems Huang Weihua, Fujian Province, post and telecommunications engineering company opened a test in the end found that all public telephone calls to make long-distance phone no reverse signal, dial local network users have a negative signal. Check user data, these public phones have reverse polarity . As the local network users also have anti-polar signal, so doubt asked ...