signal. In repeater systems, the voted signal is retransmitted. In simplex systems, it goes to the console speaker at the base station. Audio from a receiver that is not voted is ignored. Voting comparators in analog FM systems can switch between receivers in tenths- or hundredths-of-a-second, (faster than one syllable). So long as an intelligible signal gets to a single receiver in the system, the repeated audio, or audio sent to the console speaker, would be intelligible. In this arrangement, receivers at remote sites are connected to the voting comparator by private telephone lines, a channel in a D4 channel bank on a DS1, or an analog microwave baseband channel. How signals are evaluated The earliest voting comparators relied on a tone encoded on a separate audio path, requiring each receiver site to have a 4-wire circuit or two audio paths. The pitch of the tone changed to represent the received signal level, or FM receiver limiter voltage, at the remote receiver. This worked poorly because it did not account for microwave baseband noise or noisy telephone company circuits. Newer voting comparators compare signal-to-noise ratio at the voting comparator, accounting for end-to-end noise, bad phone lines, poor level discipline, as well as the best diversity reception path. Walkie-talkie talk-back range When communicating with hand-held radios (walkie-talkies), base stations generally talk out further than they can receive. Voting among several receivers at different sites increases the probability that one of the receivers will acquire a usable signal from two-way radios in a system. Interference reduction Diversity combining reduces one possible single-point failure: any single receiver failure, or local interference to a single receiver, will not block reception on the entire system. Equipment sites can host many radio transmitters and receivers. A single site is subject to local, site-specific interfering signals. These interfering signals may come and go as transmitters switch on and off. A potential problem with receivers located at high-elevation receiver sites is that they may acquire signals from distant counties, prefectures, or other provinces. These unwanted, distant signals can be stronger than desired signals from local walkie-talkies. The distant signals may block local weak signals in some cases. Having several receive sites increases the probability that one of the sites will receive the local signal in the presence of a distant, undesired one. Selective calling can eliminate users having to listen to the audio of distant signals even though