This step attenuator was constructed based on the ARRL HANDBOOK (19.52 A SWITCHED ATTENUATOR). It has 1dB, 2dB, 4dB, 8dB,10db and two 20dB switchable attenuators built using 1% metal film resistors and toggle switches (offering a maximum of 65dB attenuation in 1dB steps). The shielded enclosure is made from copper sheet and is covered with heat-shrink tubing. Connectors are BNC. Maximum power handling is about 300mW, although it can handle more for brief time periods. It works excellent at HF and is usable up to 2 meters.