This show has been flagged as Clean by the host. Goal: send a voice signal on VHF or UHF, receive and record with SDR via RTL dongle Core Problem and Resolution An issue may have been a hardware I/Q Imbalance in the RTL-SDR, which suppressed the desired signal, resulting in very low output volume that required excessive manual amplification. Initial Problem: Very quiet, barely audible recorded audio, initially on UHF 433 MHz Key Discovery: An I/Q imbalance caused a repeating signal "image" in the spectrum, Frequency Change: Switched to the VHF 145.500 Mhz band, Gain Override: To overcome the defect and the failing AGC, gain stages were manually adjusted: Squelch: Squelch (SQL) was set to OFF (0) to prevent the software from muting the quiet, legitimate signal. Adjusted the final Sound Output/Recording Gain on the host OS to match the maximized digital output, achieving audible voice. Summary of Key Radio and Software Settings Transmitting Radio (Baofeng UV-5R): Operation: Simplex (direct radio-to-SDR). Mode: Narrowband FM (NFM). Receiving Software (SDR++): AGC: Disabled (Crucial override). RF/Tuner Gain: Adjust (Inject best signal power). AF Gain: Adjust (Produce loudest digital audio). Squelch (SQL): OFF (0) (Prevent muting of quiet signal). Filter Bandwidth: 12.5 kHz(Correct setting for NFM). The ultimate resolution was forcing input and output gain in SDR++ and volume adjustment in Audacity Provide feedback on this episode .
