Voltage is measured across the entered real resistance: P = Vrms²/R. Peak and peak-to-peak values assume a sine wave. These are loaded-voltage conversions, not open-circuit source voltage or radiated field strength. dBu uses a fixed 0.7746 V reference regardless of load.
1. Power Conversions: $P_{\text{dBm}} = 10 \log_{10}\left(\frac{P}{1\text{ mW}}\right), \quad P_{\text{dBW}} = 10 \log_{10}\left(\frac{P}{1\text{ W}}\right) = P_{\text{dBm}} - 30$
2. Voltage & Impedance Relationships: $V_{\text{rms}} = \sqrt{P \cdot Z_0}, \quad V_{\text{dBV}} = 20 \log_{10}\left(\frac{V_{\text{rms}}}{1\text{ V}}\right), \quad V_{\text{dB}\mu\text{V}} = 20 \log_{10}\left(\frac{V_{\text{rms}}}{1\ \mu\text{V}}\right) = V_{\text{dBV}} + 120$
3. Audio dBu (fixed voltage reference): $V_{\text{dBu}} = 20 \log_{10}\left(\frac{V_{\text{rms}}}{0.7746\text{ V}}\right)$, where $0.7746\text{ V} = \sqrt{1\text{ mW} \times 600\ \Omega}$.