Power Splitter

[actlitedeuter]

How do I measure the loss on one port of a four way 0 degree 50 ohm power splitter? Do I have to terminate the other ports? Or should I leave the other ports w/ no connection?

 

[Comcokid]

In normal operation, the other ports will be connected to devices that are 50 Ohm loads. If testing the device, terminate the unused ports. Depending upon the port-ot-port isolation charcteristics of the splitter, terminating the other ports may not affect the readings on the port you are testing much, but they should be terminated to get proper reading.

 

[Higgler]

Sound right Comcokid. 50 ohm loads are required to be on the other ports for accuracy. You will measure 6.02 dB loss from the input to one output if the unit is no loss. If you measure 6.52 dB, then that path has 0.5 dB loss in reality. When you split one path to 4 paths, there is 10*log(4) or 6.02 dB per path power reduction due to the split.

One other slightly less accurate way is if you have two identical units and simple (equal phase equal loss) adapters that can connect them together. Connect the two together and measure in one and out the other, divide loss by 2 (in dB).

kch