 It is not uncommon for several Wi-Fi networks to be within range of a typical home and as such, spread-spectrum based video senders are often the best solution for transmitting audio and video signals within this crowded wireless environment.Some manufacturers use proprietary spread-spectrum techniques, enabling typical operational ranges of up to 80 metres in-building.By also employing externally mounted antennas, operational ranges in excess 2000 metres (clear line-of-sight) have been achieved and several such models are sold under the Digi-Sender brand.