Hello there, QRZers! o/ I'm working on a personal project to embed a SDR inside a FT-991A. This project is a hard hack on something that it was already being done. Check the vanilla instructions in https://c.rf01.co:8443/q/pat-70-ft-991a.pdf . I don't like the idea of drilling a hole in my radio's chassis. And I thought... What about if the radio had a SDR INSIDE it, and exported through its USB port, without hanging or extra wires, ports, etc.? THAT would be slick. After a full sunday brainstorming the idea, reading datasheets and using the radio schematic as a source for inspiration, I have come out with the schematic in https://c.rf01.co:8443/q/panadapter.pdf . So, this is obviously designed by someone without a degree in Electrical Engineering, and I have used the Radio's schematic as a source of inspiration for the decoupling and stuff. The part that I actually designed was the "Signal Control Board", where I have a AND port to bias a transistor which will actuate a solid-state analog switch, which will connect or not the RF signal from the radio's IF tap to the Buffer Board & SDR. Since this is going to be installed in a RF-harsh environment (inside a 100W transceiver, though not on the same board as the RF PA unit) AND, to make things worse, where the RF quietness is highly critical (this is actually close to the tuner stage), I was wanting to check with you guys: 1. Is the Q1 & U2A in Signal control board correctly designed? I'm under the impression that I should have used a PNP here instead; 2. Does the decoupling look sufficient? 3. Any shielding suggestion/recommendation, etc.? 4. In the original project, the PAT-70 IF input uses just a as-short-as-possible standard wire. What about using a co-ax? 5. Any other ideas? Appreciate your awesomeness ;-) 73s de PY2RAF.