Radio and Electronics Cookbook

71

Adding the 80 metre band to the Yearling receiver

Background

You will have noticed that your Yearling receiver has a dial which shows coverage of the 80-metre amateur band (3.5–3.8 MHz). This band is used for local contacts during the day, and contacts up to about 1600 miles in darkness. Longer distances are possible, particularly in the middle of winter.

The modifications

Only a few extra parts are required, as you may have noticed from the parts list. A low-pass filter, FL1 (one which passes low frequencies and rejects higher frequencies), is switched into the circuit on 80 m. The circuit of the switch and its connections is shown in Figure 1. Before making the modifications, dismantle the receiver so that you have easy (and safe) access ...