Which cable to use for least cable loss in decibels (dB)?

Long cable runs will cause some dB loss and unfortunately there's no way around it. However, you can minimize loss incurred by using as minimum length cable as possible. You can also make choices that prevent higher loss by choosing the type of cable being used. Another fact you cannot bypass is that the higher the frequency band Megahertz, the higher the loss. For example, the 700 MHz band will lose roughly 3 dB per 100 feet, the 2100 MHz band will lose roughly 7 dB per 100 feet with Type 400 cable. Smaller cable (example RG6) will have more loss. Larger coax cable (example LMR-400, Wilson-400, SureCall SC-400) will have less loss. For long cable runs (100 feet+), using Cable Type 400 or even better Cable Type 600 Low Loss Coaxial Cable is best for least amount of signal loss due to cabling.