Richard Emsley
Mesuro Limited
8th Floor Eastgate House
35-43 Newport Road
Cardiff CF24 0AB
United Kingdom

RE: The tariff classification of an active harmonic load pull system from Great Britain

Dear Dr. Emsley:

In your letter dated August 10, 2011, you requested a tariff classification ruling. No sample was provided.

The merchandise at issue is referred to as the MB open loop active harmonic load pull (AHLP) system. The MB open loop AHLP system is a modular test system used in the testing of semiconductor power amplifier devices. You indicate that the modular nature of the system allows a user to utilize the system to cover different electrical frequency bands and power levels when performing tests. The AHLP systems are imported in different configurations, depending on the output power levels of the devices under test (for example, the MB20 is intended to test devices of up to 20 watts nominal output power, while the MB150 tests those with up to 150 watts nominal output power). The MB AHLP consists of individual modules that make up the system. These include a radio frequency (RF) test set and a multiplexer. The system operates by placing a semiconductor device under test (DUT) in a test fixture that is connected to the MB AHLP system. To perform a test the system instructs a third party signal generator to provide an appropriate signal. The signal passes through the multiplexer, which conditions it in accordance with the test being conducted, where it is then sent to the RF test set, which delivers the conditioned signal directly to the DUT. The RF test set also incorporates signal detectors that take the signals generated by the DUT (in response to the conditioned signal it received) and sends that output to receivers incorporated into the system. The receivers then send this data to the MB control system where the results are analyzed and displayed. The tests performed by the MB AHLP system allow a user to determine how the DUT responds to certain electrical inputs, and whether the output generated by the DUT falls within the expected parameters. The system can measure the current and voltage waveforms generated during the test, and determine how much current can be passed through particular DUT and at what frequencies. Software included with the system allows a user to display the results of each test on the control screen. It further allows a user to view and plot all of the measurement data graphically, and has the capability to display recorded waveforms both while the test is underway and after it has been completed.

Based on the information you have provided, the MB AHLP open loop system is measuring and checking a variety of electrical process variables, and using that data to determine whether the semiconductor power amplifier devices being tested are operating properly. The system is capable of analyzing the measurement information it receives from the tests to determine not only if the devices under test are operating as expected, but also to see how the DUTs respond to different types of electrical signals (with varying voltages, frequencies, etc.). The data obtained during the tests can be stored as generic MDIF files (measurement data interchange format), which indicates that the MB AHLP system incorporates a recording capability.

The applicable subheading for the MB Active Harmonic Load Pull system will be 9030.84.0000, Harmonized Tariff Schedule of the United States (HTSUS), which provides for Other instruments and apparatus for measuring or checking electrical quantities, with a recording device. The rate of duty will be 1.7 percent ad valorem.

Duty rates are provided for your convenience and are subject to change. The text of the most recent HTSUS and the accompanying duty rates are provided on World Wide Web at

This ruling is being issued under the provisions of Part 177 of the Customs Regulations (19 C.F.R. 177).

A copy of the ruling or the control number indicated above should be provided with the entry documents filed at the time this merchandise is imported. If you have any questions regarding the ruling, contact National Import Specialist J. Sheridan at (646) 733-3012.


Robert B. Swierupski
National Commodity Specialist Division