Level and power measures | |
dBµV | Voltage level in relation to 1 µV (Interpretation: “by how many dB is a voltage higher than 1 µV”) |
dBmV | Voltage level in relation to 1 mV (Interpretation: “by how many dB is a voltage higher than 1 mV”) |
dBm | Power level in relation to 1 mW (Interpretation: “by how many dB is a power higher than 1 mW”) |
Converting formulas |
dBµV = dBmV + 60 dB |
dBmV = dBµV – 60 dB |
dBµV = dBm + 108.75 dB (with Z = 75 Ω) |
dBµV = dBm + 107.00 dB (with Z = 50 Ω) |
Frequency bands | |
HF: High Frequency | 3 MHz … 30 MHz |
VHF: Very High Frequency | 30 MHz … 300 MHz |
UHF Ultra High Frequency | 300 MHz … 3 GHz |
Level relations in a broadband cable network | |
System level (traditionally) | PAL image carrier level |
DVB-C / DOCSIS <= 3.0 @ 64 QAM | PAL – 10 dB |
DVB-C / DOCSIS <= 3.0 @ 256 QAM | PAL – 4 dB |