The Alinco DR-635T is a twin band mobile transceiver operating on the 2 meter and 70 cm bands. It has transmit coverage from 144 to 147.995 and 430-449.995 MHz. SDR# can show you the audio tone being used, but you'd need an SDR dongle receiver, an antenna, and the audio from the station transmitting. Inexpensive frequency counters (check EBay) with CTCSS decoders can also do the job and will even detect digital tones.
ComTekk Multi Decoder makes use of the computer sound card and software DSP (Digital Signal Processing) techniques to decode and instantly display paging, DTMF, and CTCSS tone-encoded information. ComTekk Multi Decoder will listen for any sustained tone signal and display the frequency or frequencies. ToneLCD Direct Reading CTCSS Tone Encoder / Decoder. $89.00... more info: TSU-5Dpx Dual Tone Decoder for the TS-790A. $119.00 ... TU-79px Tone Encoder Board for the... CTCSS (Continuous Tone-Coded Squelch System) – This is a sub-audible tone transmitted by your radio in addition to your voice signal. When it is equipped with a CTCSS decoder, a repeater will not function unless it hears the CTCSS tone and the “carrier” signal from your transmitter.