Short-range-radio co-existence is now possible using CTCSS carrier generation with a 256-B sine-wave lookup table. To allow multiple users to share one carrier frequency, many handheld transceivers ...

I chose to look at the frequencies in the low range of CTCSS tones (67 to 100Hz) because these are the closest together, with a minimum tone spacing of 2.5Hz between tones 2 (71.9kHz) and 3 (74.4kHz), ...

The AK2345 is an IC which supports CTCSS (Continuous Tone Controlled Squelch System), compatible with TIA/EIA-603 standard. A single CTCSS may be selected from among 50 different frequencies within a ...

In the first part of our series on in-band signaling, we discussed one of the most common and easily recognizable forms of audio control, familiar to anyone who has dialed a phone in the last fifty ...