For testing out transmitters every ham should have a dummy load. The project I'm describing here is usefull up to 30W. The parts used could allow up to 50W but there is no vents in the chassis.
The 26 resistors were soldered in parallel. One end was connected to the chassis. The other end was connected to the center pin of the BNC connector.
I realize that there isn't much here. But hopefully the pictures give you some ideas. Use whatever parts you have on hand. The goal is to get a resistive load of 50 ohms. Good luck.