Hi @donmichaels1, and welcome to the MetaGeek Community! Thanks for you post, that is a wild-looking screenshot. I can say with very close to 100% confidence that those readings of 0 dBm are incorrect. I haven’t done the math in a while, but your AP would have to transmit at a very high power level in order for your Realtek adapter to pick up 0dBm through any amount of free space.
Way back when we first wrote inSSIDer (over 10 years ago!), we used to see things like this quite a bit. Windows relies on the Wi-Fi adapter driver to get those power readings, and some drivers seem to use a 0 as a default when they didn’t get a good reading from the hardware. That seems like what is probably going on here. You could with Realtek or Windows update to see if there is an update to the driver, it might improve this behavior. In any case, I think you can safely ignore the 0 dBm readings.
Even then, it will be kind of odd to see RSSI readings bouncing between -60 dBm and -17 dBm in a fixed location. In that case, I’m still more inclined to think this is due to an anomaly in the Realtek adapter hardware, firmware or driver software that due to the actual transmitted signal from the AP varying that much from one beacon to the next.