Thank you to Fabian for writing in and sharing with us his newly released RTL-SDR close call monitoring software called "rtl-sdr-close-call-monitor". The software is open source and written in Python. It's main purpose is to log any signal peaks that appear within a defined frequency range. Over on the GitHub Fabian explains the software:

These scripts use an RTL-SDR device to detect peak signals on a user specified frequency range. The scripts can also make an automatic blacklist so that different sources of RF noise won't cause continuous false positives. There are two scripts provided as examples. The scripts can be used to monitor certain frequencies for a wide range of purposes such as:

• In criminal investigations, a close-call RF signal monitor can be used to detect and track communication signals used by criminals. This can help law enforcement agencies gather intelligence and evidence, and even prevent future crimes from being committed. By analyzing the frequency and strength of signals emitted by communication devices, a close-call RF signal monitor can provide valuable insights into the movements and activities of suspects, allowing investigators to piece together a timeline of events and make informed decisions about how to proceed with a case.
   
• In military operations, a close-call RF signal monitor can be used to identify and track enemy communication signals, providing valuable intelligence for strategic decision-making.
   
• In scientific research, a close-call RF signal monitor can be used to collect and analyze data related to wireless communication systems, providing valuable insights for thesis projects and other research studies.