Users of the iPhone have discovered that the phone has a very comprehensive “Field Test” mode that allows users to find out a range of information about the phone’s connection to the network. In particular, the information displayed in the Field Test mode allows users to discover exactly which tower their phone is connecting to, and which frequency band the signals are being sent on.

Here are some simple instructions to find out which frequency your iPhone is using:

1. Access the iPhone’s Field Test mode by typing *3001#12345#* in the phone’s keypad and press dial. This will bring up the Field Test menu.

2. Select the “Cell Information” menu option to display a summary of all nearby towers. The “RX” code displays the signal strength of each tower. These RX values are dBm signal strength readings, where lower values means strong signal (so -60 signifies stronger signal than -80). The towers are listed by signal strength, and the top tower is usually the tower your phone is connecting to.

3. Selecting the first tower will take you to a further menu that displays more specific information. The “Freq” value shows the frequency block that the network is using. If the Freq number is between 128 and 251, the tower is using the 850 MHz Cellular band. If the Freq number is between 512 and 810, the tower is using the 1900MHz PCS band.

Over the weekend, hundreds of thousands of users switched over to the AT&T network to take advantage of Apple’s iPhone. Unfortunately, AT&T’s network is often spotty, and EDGE data rates are constrained by the quality of the signal. One way of improving AT&T coverage and ensuring fast EDGE rates is installing a cell phone repeater.

Since AT&T and Cingular merged a few years ago, the joint company has owned licenses for both frequency bands in most areas. In order to ensure an improvement on voice and data coverage, we recommend purchasing a dual band repeater for AT&T customers. Once installed, these repeaters will also improve the cell signal on every other network (except for Nextel). Here are our recommendations:

Medium reception: For users with medium signal quality outside their building (3 bars or more), the zBoost YX-510 kit will improve your cell phone signal to full bars for AT&T voice and data services, even if you currently have no AT&T service at all inside. This unit will usually cover up to 2,500 square feet. The kit is very easy to install, and comes with everything needed to set the system up. You can find our product page here: Wireless Extender zBoost YX-510.

Low reception: For users with low quality outside their building (2 bars or less), the YX-510 kit Premium Kit can be used to amplify the AT&T signal. This repeater will usually cover up to 3,000 square feet (or 5,000 square feet if you currently have 3 bars or more of signal outside). You can find our product page here: Wireless Extender zBoost YX-510 (scroll half way down the page).

Large coverage areas: For users with 2 or more bars of signal outside their building, and who wish to cover up to 10,000 square feet, we recommend : Digital Antenna DA4KSBR-50U 60dB Repeater Kit (scroll half way down the page). This more powerful antenna also comes with a high-gain omni-directional antenna, and is perfect for large-building installations.

If you have any questions about repeaters, or want a custom recommendation, feel free to call us at 1-800-761-3041 or e-mail us at support@repeaterstore.com.