Just as January and February were good times to be buying rice, beans, respirators, gloves, rubbing alcohol, and sanitizing solution, now is a good time to be buying equipment for situational awareness in November. There are basically three modes antifa may use: (1) bubble-pack, (2) Baofeng, and (3) something else.
Bubble-pack is any pre-channelized retail radio, such as FRS, GMRS, MURS, or CB, with FRS and GMRS being most common. Their frequencies are pre-determined, so it doesn't take any effort to hunt them down, whether using another radio, a scanner, a frequency counter, or a dongle. Baofeng has default frequencies, which are as easy to find as bubble-pack, or they can be programmed anywhere in the 136-174 or 400-520 MHz ranges. Some of the newer ones also include 220-260 MHz. A scanner with a search function or a dongle can find the frequency. A frequency counter requires close proximity and just displays a frequency, so something else is still needed to listen. Proximity to antifa can be unhealthy, so rather than getting within a few feet to use a frequency counter or a mile or so to hear them, the ideal is to position a Raspberry Pi with a dongle at an elevated location with internet access within a quarter mile or so of suspected antifa activity. Then one can ssh or vnc into the Pi and control the dongle from far away. If something other than bubble-pack or Baofeng radios are used, then more specialized techniques may be required.