ID2011

The centering frequency is an important selection criteria because l/4 stub tuner design techniques restrict the bandwidth in which acceptable VSWR performance can be achieved. Stub tuners exhibit a v-shaped VSWR response.Typically this bandwidth is 8% of the centering frequency.Specified bandwidth in excess of 8% begins to experience degradation of VSWR at the centering frequency. Stub tuners are frequency specific in application as opposed to surge protectors which address a wider spectrum of frequencies. As a result of this restriction, M/A-COM offers a wide range of standard stub tuner devices which address commonly deployed cellular frequency bands such as GSM, NAMPS, PCS 1900 and DCS 1800.

Stub tuners, by the nature of their short circuit designs, do not have a sparkover or residual voltage as found in surge
protectors. This ensures the greatest levels of protection against repeated lightning or EMP strikes within specified frequency bands. Stub tuners are also extremely reliable and maintenance free since they contain no active parts. This characteristic can be important when considering the total cost of ownership, including the need for replacement or repair of the device within difficult to reach infrastructure equipment.

Some alternative plating finishes are available with M/A-COM's Stub Tuner Lightning products. Standard plating finishes are shown within the data sheet, but alternatives are available by customer request. Details of M/A-COM's new "White Bronze" finish are shown in the application notes associated with this data sheet. For more detailed information, please contact your local M/A-COM field sales office.