QRPGuys 31dB Step Attenuator – $30
Based on an ARRL design, the QRPGuys 31dB Step Attenuator allows you scale back the output of your qrp transmitter to lower levels. It incorporates six pi-network resistive networks. You can easily attenuate your low power rig to pursue your “Miles/Watt” goal. With our attenuator you can have 1 dB steps throughout the range. It has been tested up through 148MHz with a loss of less than 1dB. There is also a bypass switch that you can easily throw and not attenuate in receive mode, without having to return all the switches to bypass. The design can be used as is, or allows mounting the BNC connectors and resistors on the back side to permit mounting in a chassis if you desire. With the use of 3W resistors you can safely use 10 watts cw figuring a 50% duty cycle. The kit is all contained on a 6.12″ x 2.00″ pcb, and has female BNC connections. On a difficulty scale of 1 to 5, 5 being the most difficult, this is rated at 2.