31.325 MHz coming in very nicely at 1020 local time (US Eastern Time) polytone data signals. French traffic control traffic signal control link system EPAR - I've seen it referenced as EPARS as well. Receiver location: Richmond VA. Pro-106 scanner with HYS 51 inch telescoping CB whip antenna HYS 51" 27MHz CB antenna. Also can hear it with the RadioShack center-loaded scanner/ham antenna 20-006 20-006A and the Cobra HA-TA 27" telescopic CB radio whip antenna with BNC connector "HT-1" antenna, sold under many names. It is also base-loaded and Cobra HA-TA seems to be the most common brand name and model for that particular antenna. Just like the HYS 51" antenna, simply reducing the length ever so slightly makes the antenna resonate in the 30-35 MHz region.
Known to use the following additional frequencies:
31.4375 MHz
31.4625 MHz
31.6875 MHz
31.925 MHz
31.975 MHz
31.325 and 31.975 seem to be the most commonly heard, along with 31.6875 MHz. They come in nicely in NFM mode, but also in USB or LSB. 31.6875MHz tunes in fine on 31.690 MHz or 31.685 MHz if you're stuck in the proverbial 5 kHz steps land.
31.325MHz sometimes has voice comms on it, either Asian fishery radio (27.5 MHz - 39.475 MHz, 25 kHz steps, NFM with carrier squelch (CSQ) simplex only, various LMR systems, a paging system operating on 31.320 MHz (unknown location), US based two way radio systems also on 31.3200 MHz 31.32 MHz and of course military FM comms on 31.325 MHz FM 30-88 MHz.
The EPAR system data sounds very similar to digimode ROS (it sounds very musical). In addition to the amateur bands, ROS can be found on 27.635 MHz, 26.735 MHz, 26.740 MHz, 27.235 MHz and 27.245 MHz on the 11 meter CB radio band. 27.235 and 27.245 being CB radio channels 24 and 25 respectively. Most of the time it’s in FM mode but USB has been noted as well, especially on 27.635MHz.