CELLULAR SIGNAL BOOSTING
Voice quality and proper operation of this interface equipment is dependent on the signal quality of your cell phone reaching the nearest cell site. Many inside locations may not require an external antenna. If your cell phone works well at the location that the interface equipment will be placed (3 or more bars or upper 3/4 or higher on the phone's signal strength meter) then you don't need an external antenna. With marginal signal strength at the planned location ( 2 bars or middle of the meter) you should purchase an external antenna for best performance. A low signal strength (1 bar or 1/4 or lower part of the meter) indicates the absolute need for an external antenna and possibly a powered signal booster. You should also try different indoor locations where you plan to place the interface equipment to see if any of those locations improves the cell phone's signal strength before deciding on purchasing an external antenna. An external antenna must be connected directly to the cell phone as this equipment is only a telephone interface unit does not have an antenna connection nor does it boost the cellular signal. D&J Enterprises supplies a variety of external antennas and connectors ie: the new Freedom Universal Booster antenna from Phonelabs, omni-directional antennas, yagi antennas, panel antennas, marine antennas, low-loss cables, signal boosters, and repeaters.
If you are wanting to use this interface equipment with more than 5 or 6 wired phones, D&J Enterprises can supply you with a "Ring Booster" that will increase the 3 REN (Ringer Equivalency Number) of the interface equipment to 15 REN allowing the your unit to ring up to 15 phones. These "Ring Boosters" run $250 and are a special order item.