I’m adding the available RTL-SDR-compatible foundation now: USB-C, RTL2832U, EEPROM, 3.3 V regulator, USB protection, SMA antenna connector, and the key support passives. The missing tuner/clock parts will stay documented as open items rather than using fake placeholders.
Built the RTL-SDR-compatible schematic foundation for the P25 receiver: USB-C, RTL2832U, EEPROM, AP2112 3.3 V power, USB protection/choke, SMA input, decoupling, and tuner-interface nets. I also created the project spec here: Project Specification. Latest check showed no open ERC warnings/errors, but I have to stop because your account has no available ACUs right now.
Open items:
Rafael R820T2/R828D/R860 tuner IC is still missing from the Flux library.
Exact 28.8 MHz RTL2832U clock part is also missing.
This is not yet a working receiver until those two blocks are added.
Suggested next steps:
Add/create the missing tuner and 28.8 MHz clock parts.
Finish the RF front end and tuner wiring.
Re-run schematic review.
Move to 4-layer PCB layout with USB differential routing and 50 Ω RF routing.
Wirelessly connects nets on schematic. Used to organize schematics and separate functional blocks. To wirelessly connect net portals, give them same designator. #portal
General Purpose Thick Film Standard Power
and High-Power Chip Resistor
47 kOhms ±5% 0.125W, 1/8W Chip Resistor 0805 (2012 Metric) Automotive AEC-Q200 Thick Film
Features:
- RMCF – standard power ratings
- RMCP – high power ratings
- Nickel barrier terminations standard
- Power derating from 100% at 70ºC to zero at +155ºC
- RoHS compliant, REACH compliant, and halogen free
- AEC-Q200 compliant