Home Brew 60W RF Dummy Load

Another great way of making your own 60 watts dummy load is by the use of Caddock thick film power resistor.  Purchased some of these at http://philippines.rs-online.com/web/ which cost  at 270 Pesos each. Two 100 ohm / 30W resistors were paralleled to make a 50 ohm / 60W dummy load. The good thing about this product is that it comes in TO-220 package and mounting this on a suitable aluminum heat sink is a big help in heat dissipation during actual use. Been able to test my prototype on VHF and provides a very good matched at 144MHz exhibiting an SWR value of 1.1:1 across the amateur band due to the fact that reactive components can be easily minimized because of the unique package of this resistor.

Thermal compound was added between the aluminum surface in contact with the power resistors. A pig tail coax to PL259 connection was also included but a slight increase in SWR was noted. 73 de du1vss