Vol. IV — Electronics · Tool
Power and voltage ratios in decibels, plus absolute levels in dBm and dBW. Change the knobs — the other side updates as you type.
Power ratios use 10·log₁₀(P₂/P₁). Voltage (or current) ratios at the same impedance use 20·log₁₀(V₂/V₁). Doubling power is about +3 dB; doubling voltage is about +6 dB.
0 dBm is 1 milliwatt into a reference load (often 50 Ω in RF). dBm = 10·log₁₀(P_mW). dBW is the same idea referenced to 1 watt: 0 dBW = 30 dBm.
Pair with Q-factor for bandwidth in Hz, or Impedance for |Z| and phase. Back to the electronics bench.