In today's podcast we talk to Larry Yost, Design Engineer at API Technologies, who is speaking with us about the new Band Reject Filter, the CMN719.

Hosted by Janine E. Mooney, No Strings Attached - Your Wireless Broadcast is Wireless Design and Development's web-based interview show where we talk about the latest wireless technology, components, and design issues for the wireless design engineering community.


Band Reject Filter Eliminates AWS Interference at ENG-RO Sites

API Technologies Corp. announced it is now taking orders for the CMD719 band reject filter designed to eliminate Advanced Wireless Services (AWS) interference of electronic news gathering receive only (ENG-RO) sites. The CMD719 will be on display at Booth #1306 during the IEEE International Microwave Symposium (IMS2012) taking place now through June 21 at the Palais des Congrès in Montreal.

The CMN719 Band Reject Filter eliminates brute force overload interference (BFO) of ENG-RO sites caused by AWS operators transmitting at 2110.6 to 2121.5 MHz. It is critical to the preservation and operation of TV BAS Channel A7 which operates at 2097.5 to 2109.5 MHz, and its group delay does not degrade digital ENG signals.

“Television stations use the BAS frequency band to relay signals from remote news trucks back to the station,” said Jerry Roberds, Vice President of Engineering, CMT Filters Commercial, Defense and Space Filter Product Group of API Technologies. “The AWS band that cell phone companies use sits right next to the BAS band. Oftentimes, the AWS cell site overwhelms the TV station receivers on the BAS band. By inserting the CMN719 between the TV station’s receive antenna and its BAS band receiver the AWS frequencies are blocked and the TV relay signals are uninterrupted.”

The CMN719 attenuates AWS frequencies 2110-2121.5 MHz by 60dB minimum while passing BAS Channels A1-A7 (2025.5-2109.5 MHz) with a specified 1.60dB maximum insertion loss. Typical worst case insertion loss of 1.50dB occurs at the extreme band edge of Channel A7 at 2109.5 MHz. It is configured with a 19” 2U rack mount panel and has type –N female connectors.

“As the FCC continues to shoe horn more and more users in tighter and tighter bands of frequencies the need for more selective filters will be required,” added Roberds.

For more information about CMN719 Band Reject Filter, please visit



August 27, 2012