I'm on the hunt for a cheap and simple tool to capture Bluetooth classic packet traces. Not BLE or I'd just use the $25 Adafruit nRF51 based sniffer. Only really interested in high-level protocols, more specifically determining why a particular BT device fails to connect to a car head unit. So I imagine a simple and cheap solution is a sniffer (ISM band SDR based, or PC host based if the BT radio can be put into promiscuous mode) that captures and dumps packets to a pcap file to look at in wireshark, not unlike what one might do with a crude tool like tcpdump. I don't really need precise timestamping, real-time capture and view, compliance verification, etc etc. Just dump the traffic to a file then filter and decode offline. I can even set up a controlled environment where there's guaranteed not to be any other BT radios. This is pretty much a one-off so I don't really see much need to spend thousands on it. Help!