CW-BC Audion 7 MHz

This very simple receiver is designed for beginners. It uses the known schematic diagram: aperiodical preselector, audion and audio-amplifier. Receiver tuned on popular fourty-meter band, in two sub-bans: One is for amateur radio (CW mainly), from 7,0 to 7,1 MHz. The other is for broadcast (BC), from 7,1 to 7,4 MHz.  With external antenna "short wire" (about 10 m of wire) you can hear many stations there, mostly the whole day.

The inductivity is on the ferrite toroid core, diameter 10 mm, permeability 50. The coil L1 has 2 turns, L2 has 2+9 turns, wire is 0,3 mm.

The setting of both sub-bands is best done with a counter. Capacitors C6, C9 are for the CW sub-band, C7, C10 for the BC sub-band. If you need more capacity, sold it paralell to the relevant variable capacitors. The tap on the coil L2 has 1/5 threading.

Why is the BC band added? So you can hear the many BC-stations and their music hits from all continents which you can`t hear on your normal FM receiver ...

Experimental construction without the aperiodical amplifier.

Receiver is nearly complete.