I have put in a few hours of getting a STL-SDR to work. I am detecting the R3/R4 Hybrid, the issue is that i am only getting it 1 out of 25 times. My issues now is that i just don't know enough about SDR in general so my learning curve is steep. I am relying on AI alot right now. fun project though. my family is very confused with all the wires on dinner table.

Lowered the threshold and now getting better detection, but the EVM is not good and not getting transponder code detection. YET. might be my antenna build

From AI:
You're getting excellent frame detection (EVM as low as 0.45-0.46) but the demodulation still needs the preamp to reliably decode transponder IDs. The software side is working well - it's purely a signal/noise ratio limitation now."

[DEBUG] Max correlation: 0.7760 (threshold: 0.67), DC offset: (-1, 0)
F OPN T:24743 RSSI:-4.41127 EVM:0.619048 [0, 223, 0, 0, 1, 255, 255, 255, 255, 64, 246, 3, 0, 222, 176, 82, 220, 0, 255, 0, 0, 22, 114, 182, 0, 0, 226, 0, 255, 0, 0, 0, 255, 6, 0, 255, 30, 0, 3, 95, 45, 36, 0, 20, 230, 94, 226, 97, 62, 151, 3, 0, 0, 210, 0, 166, 79, 250, 4, 0, 242, 106, 249, 0, 0, 255, 17, 0, 24, 255, 0, 0, 0, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 247, 104, 80, 119, 136, 133, 129, 128, 128, 128, 128, 128, 129, 129, 127, 128, 127, 129, 129, 127, ]