rf shield

Well I have reached the limits of my wisdom and now I seek advice among the professionals here in the Forums. Let me quickly describe the project I'm working on: The goal is that a LoRa Receiver can detect the direction of addressed LoRa Signals (home in on the Transmitter basically). My...

I am repairing a PSR-500 where I need to remove the RF shield near the BNC antenna connector. I have all the desoldering tools, so that is no problem. However, they've now added some sort of brown "glue" on top of several of the solder joints. Has anyone run into this before? What is the...