Tim Hardy, Nautel's Head of Engineering


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Nautel’s NX Series offers:

  • Industry’s top efficiency: up to 90%
  • AM precorrection for increased linearity
  • 2.7 MHz Direct Digital Modulation
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  • 100% remote access to the user interface
  • RF and audio spectrum analyzer
  • Integral Digital: HD Radio, all DRM modes
  • The new standard in compact AM design

NX Series

Learn more about Nautel’s NX Series AM transmitters with power levels ranging from 1kW to 2000kW


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Saving Power with MDCL now FCC Approved


Tim Hardy, Nautel’s Head of Engineering has long been an advocate of “Energy Conservation in AM Broadcast Transmitters Using Carrier Control Algorithms” the topic of a paper he presented at NAB in April of 2009. In fact, Hardy has been working with such technologies, known generally as Modulation-Dependent Carrier Level (MDCL) in Nautel transmitters since the mid 1990s and most recently lobbied the FCC to establish procedures for the use of Carrier Control Algorithms by AM broadcasters in the U.S.

On September 13, 2011 the FCC Media Bureau announced that it will permit use of energy-saving transmitter technologies by AM stations. MDCL control technologies or algorithms, have long been used by international broadcasters operating high-powered AM transmitters to reduce transmitter power consumption.

While some broadcasters may have concerns over audio quality, the FCC notes “the long experience of transmitter manufacturers and broadcasters abroad, and the initial reports from experimental operations in Alaska, however, indicate that such adverse effects are generally imperceptible.”

How Much Could You Save? A Station Power Usage Example

The current average residential rate in the US is close to 10 cents per kilowatt hour and some regions exceed 25 cents. An older tube type 50 kW transmitter might operate with an electrical efficiency factor (RF power output divided by AC power input) of around 70%. Assuming an additional 10 kW of radiated sideband power, this transmitter will consume nearly 86 kW. The daytime yearly energy usage of this station (assuming a 12 hour day) would be 377,000 kilowatt hours per year for an average cost of $38,000. Depending on the night time status, this station could use up to $76,000 annually.

Using the above-mentioned MDCL technologies (standard in Nautel’s NX Series) one can realize power reductions of 30% (or more) for annual savings of $22,000 plus. For customers with an NX, Nautel’s AM transmitters with exceptional efficiency of up to 90%, the overall savings including MDCL could be up to $35,000 per year.

By combining both the NX’s built-in efficiencies and MDCL technology, cost savings of this magnitude can repay the capital investment for a new transmitter in just a few years. Over the life of a 50 kW transmitter cost savings easily exceed $500,000.

MDCL Included Free in Every NX Transmitter

When the first NX rolled out in 2008, Tim Hardy urged the rest of the Nautel management team not to charge extra for MDCL technology but to include it for free and provide it as a standard pre-installed software feature (i.e. not an optional circuit board) in all NX Series transmitters (now available in models from 25 kW up to 2 MW).

Read More

AM Power Saving FAQs
WEBINAR: AM Power Saving Techniques, Oct 19, 2011
Crawford Sees ‘Very Tangible Savings’ With MDCL, Radio World 3/6/2012
Customer Story: Crawford’s KCBC Experiences 21% Savings using MDCL
Crawford Saving Money With MDCL, Radio World 02.01.2012
KSPN Is Running MDCL in L.A., Radio World 01/06/2012
KLTT(AM), Denver is Employing MDCL on Nautel NX50, Radio World 01/05/2012
A Break for Your AM Station’s Power Bill, Radio World 9/13/2011
Alaska Test Produces Lower AM Power Costs, Radio World 4/5/2011
Saving Power Costs in AM Transmitters, Tim Hardy 5/25/2010
Energy Conservation in AM Broadcast Transmitters Using Carrier Control Algorithms, Tim Hardy NAB 2009

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