zBoost ZB645SL-CM

ZB645SL-CM (Discontinued)

zBoost dual-band signal booster with ceiling-mount antenna covers up to 7,500 sq. ft.

Setup Overview:

Everything you need is included: amplifier base unit, indoor ceiling-mount antenna, power supply, (2) 15 ft. and (1) 35 ft. of RG6 cable, flat window entry cable, external antenna, and mounting hardware.

 zBoost PRO signal booster illustration

FIRST: Install the External Antenna

Choosing the best location for installation of the External Antenna provides the best performance and the largest area of improved signal. Determine the location which provides the strongest signal using the signal strength indicator on your cell phone. The location will also need to provide 15 feet of vertical separation between the External Antenna and the planned location of the Indoor Antenna. Typically, the best location for the External Antenna is found on the roof.

The YX699 Signal Meter (available separately) provides signal strength information. It can be used with its supplied whip antenna to find the best location for antenna mounting with the strongest received signal. It can also be connected to the directional antennas to aim the antennas for maximum received signal.

Caution: Avoid placing antenna near metal such as wiring, A/C ducts, truss plates, etc. When attaching the cable to the antenna, run the cable away from the antenna. Avoid draping the coax near the antenna.

When you have determined the location of the strongest signal, install the External Antenna to a mast or pole (not provided). Loosely connect the antenna to the mast to allow the antenna to be reoriented for strongest signal.

Antenna Aiming

To get the maximum benefitt, you will want to take special care in aiming the antenna in the direction of the best signal for your wireless service provider. See the User Manual for Antenna Aiming Instructions or refer to our Install Tips page. You may wish to use a YX699 RF signal meter to help during this process.

SECOND:  Install the Base Unit and Indoor Antenna

The Base Unit can be easily mounted on a wall by first removing the bracket from the Base Unit and using the provided mounting hardware to affix to wall. Connect the Indoor Antenna to the 15 feet of RG-6. Then, using the TNC-F Adaptor, connect the RG-6 to the Base Unit. The Base Unit should be a minimum distance of 4-5 feet from the floor so there is clearance for the Indoor Antenna extension cable.

The Indoor Antenna should be mounted on a ceiling where increased coverage is desired. Keep the Indoor Antenna off floor and at least 3 feet away from other cords, metal objects or other wireless devices such as wireless routers or wireless access points. The zBoost performs best when there are no obstructions between the Indoor Antenna and your mobile device.

The zBoost ZB645SL-CM requires at least 15 feet of vertical separation between the Indoor Antenna and the External Antenna. Generally, increasing this distance (up to 40 feet) will increase the performance and decreasing the distance will limit zBoost performance.

THIRD: Run the Coaxial Cable between the External Antenna and the Base Unit

Connect the two provided RG-6 coax cables (35 feet & 15 feet) using the provided window-entry cable. Use the attached cables to connect the Base Unit and External Antenna  through a window, positioning the window-entry cable at the window closing.

FOURTH: Connect the zBoost Base Unit to the provided power supply and plug into a power outlet.

When your zBoost system is in place and fully connected, walk throughout your home and verify that you are able to reliably place calls. If the signal strength has improved, your zBoost is working.

Remember, coverage varies based on outdoor signal level, building construction, and antenna placement. Coverage in adjoining rooms will be reduced by walls and building materials.

Improving Your Coverage Area

Remember, coverage varies based on outdoor signal level, building construction, and antenna placement. Coverage in adjoining rooms will be reduced by walls and building materials.

Should you desire to improve coverage, you may:

  • Relocate the External Antenna to capture a better signal – higher is better.
  • Increase the distance between the Indoor Antenna and the External Antenna.
  • Purchase an upgrade antenna

Upon initial power up, the LED will cycle RED, GREEN and ORANGE for 30 seconds. After, a series of GREEN flashes will indicate the quality of your setup. Following this, a solid GREEN light indicates normal conditions. If it is not solid GREEN, follow the instructions in the Base Unit LED Indicators section in the user manual. Adjustments may be needed to optimize performance. If you find the increased signal coverage is acceptable, however, no additional adjustments are needed.
See the Base Unit LED Indicators section on our Install Tips page for more information.

Package Contents

 zBoost Base Unit Image

Base Unit

Power Supply

Power Supply

Indoor Ceiling-Mount Antenna with Connector

RG-6 cable - 15 feet

 RG-6 Cable - 15 ft.(x2)

RG-6 Coax Cable - 35 ft.

Window-Entry Cable


External Antenna

Product Specifications: ZB645SL-CM



1850 to 1990 MHz

System Gain

77 dB

PCS Bands Supported

A, D, B, E, F, C





824 to 894 MHz

System Gain

70 dB

Cellular Bands Supported

A, B, A’, B’




 Power Consumption

3W standby; 7W max signal - 2.0A Max

 Wall Supply Input; Voltage

100-240VAC 50-60 Hz; 5.0VDC

 System Certifications

FCC Parts 15 & 20, Industry Canada

 Base Unit Size and Weight

5” x 7” x 1.25” – 9 oz.

 Operating Conditions

Indoor Use Only (40°- 105° F)

 Coverage (Open Areas)

Up to 7,500 sq. ft.


This is a CONSUMER Device.  
BEFORE USE, you MUST REGISTER THIS DEVICE with your wireless provider and have your provider’s consent. Most wireless providers consent to the use of signal boosters. AT&T, Sprint, T-Mobile, Verizon and 90 additional carriers have already given consent for all consumers to use this device. Some providers may not consent to the use of this device on their network. If you are unsure, contact your provider.
You MUST operate this device with approved antennas and cables as specified by the manufacturer. Antennas MUST be installed at least 20 cm (8 inches) from any person.
You MUST cease operating this device immediately if requested by the FCC or a licensed wireless service provider.
WARNING. E911 location information may not be provided or may be inaccurate for calls served by using this device.
FCC contact information: www.fcc.gov/signal-boosters/registration