Direct Digital Synthesis is the next
evolution of analog FM broadcast systems


 CW Broadcast FM Transmitters from 50W to
                          5kW
What is Inside of My ES Series Transmitter?

We start with your Direct Digital Synthesis (DDS) digital exciter.  This exciter generates the FM signal using an amazingly high speed D to A converter.  The output signal and waveform are sent to the DDS encoder chip from the main processor.  The DDS output is buffered and amplified in several stages until it reaches around 5W of power.    In addition to creating the basic FM signal, the exciter also contains a digital stereo generator, composite & subcarrier analog audio inputs, and left and right balanced audio.  FSK signalling for FM translator legal IDs is also sent to the DDS chip from the CPU.  

What goes into a DDS Exciter?
Below is one of our DDS Exciters.  As you can see, a lot goes into it so that you can get a lot out of this exciter.
CW Broadcast DDS
                          Exciter



The exciter feeds the RF Power amplifiers.  In the ES series, the exciter directly feeds the power amplifier.  The PA uses a MRF1K50 or MRF1K80 final transistor.  These transistors are very efficient and are conservatively rated at more than 1,000W.  The most that we ever ask from these devices is around 800W, so there's plenty of safety headroom left, even at maximum output.  

ES 300
                          / 500 PA and LPF