Power Combiner Splitter - 50 input to two 50 ohm outputs, 1000 watts, 1-31 MHz
Combiners and splitters (CS) are very useful devices in receive and transmit applications where signals need to be combined (from several antennas for example)or signals need to be split (into two amplifiers for example). They can provide equal voltages, equal current, or equal power to matched or unmatched loads. How it works depends on the product selected.
The CS isolates two sources or loads from each other, but will not eliminate the effects of mutual coupling in antennas. CS types are shown in the pictures below:
Remember the source and load ports are interchangeable. In other words this device can be used to split or combine signals simply by choosing the appropriate input/output port. If we feed signals into input ports of the combiner, the output port would contain the vector sum of signals applied to the input ports shown above.
For the combiner, the output port impedance is equal to the individual input impedance when both input port impedances are equal. With two 50 ohm inputs at each input port, the output port would be 50 ohms. Likewise for the splitter, a 50 ohm input will result in a 50 ohm output for both output ports.
and combiners like this are often used in linear amplifier applications
to combine multiple power amplifiers or split exciter power so as not
to overdrive the amplifier.
The advantage of using a combiner like this is the amplifier input or output ports are isolated from each other. This reduces intermodulation caused by mixing in the power amplifiers, and improves stability by isolating amplifier ports from each other. It is much safer than simply paralleling ports.
typical amplifier application is to reduce the driving power to the
amplifier so as not to exceed amplifier input parameters such as grid
current on tube amplifiers. A typical application scenario is shown in
the figure below:
specific application for the above picture is to reduce the power input
to a linear amplifier from a transmitter which operates best at full
maximum output (which exceeds the maximum power input of the
amplifier). More specifically a Yaesu FT901 hybrid transmitter with
6146 final tubes runs most efficiently at 100+ watts output, however
many linear amplifier need only 50 watts input maximum for full output,
so some of the input power must be “dumped”. In this case the 100 watts
power output is split between the amplifier and a 50 ohm dummy load,
resulting in a maximum of 50 watts into the amplifier thereby satisfying
its maximum input requirements and not over driving the amp.
he CS-12-500 is a combiner/splitter with 2 ports for output (when
used as a splitter) and 1 port for input or 2 input ports (when used as a
combiner) and a single output port – useful for combining two antennas
into one receiver for example.
You can use a combiner for combing two antennas into one receiver or alternatively as a splitter to have 1 antenna into two receivers. If the receivers have different load impedances, the higher impedance receiver will get more signal (voltage across a higher impedance) as the splitter forces equal currents into the output ports. The CS does have an interesting characteristic. It can force equal currents into two different load impedances. Transmission lines have the effect of changing voltage and current relationships at their ports which may affect operation.
Typical loss of the CS is 3dB between input/output ports.