What is DCS or Digital-Coded Squelch in Ham Radio?

What is DCS or Digital-Coded Squelch in Ham Radio?

For the past few days I have been unable to access VU2MJJ VHF repeater most of the time, while I could check in to the morning and evening nets. This was because DCS or Digital-Coded Squelch was enabled in the VU2MJJ repeater. It was being disabled during net timings so that older stations like mine without DCS facility could also check in!

DCS which is generically known as  CDCSS or Continuous Digital-Coded Squelch System, was designed as a replacement for CTCSS. The DCS systems adds a 134.4 bps sub-audible bitstream to the transmitted audio. Telecommunications Industry Association has standardized DCS codes with 83 codes in the most recent standard. DCS avoids false keyups and prevents the repeater from transmitting continuously in response to spurious signals.