15M Regen Receiver

Given below is a simple circuit for 15M regenerative receiver. Performance is nice -  good sensitivity, adequate stability and easy to fabricate.

The same circuit can used for 20M, 40M or 80M bands by suitably changing the values of tuning components > L1, C10, VC1, VC2 & VC3.

The components values are not very critical, you may choose different types of transistors or use varactor tuning instead of mechanical air variable capacitor VC3.

TL431 based audio amplifier is easy to fabricate has good gain and no mains hum. You may choose LM386 instead.

L1 as 6 turns, ID is 8mm, OD is 10mm (1mm dia. enamelled wire) and length is 7mm.

C10 is Silver-Mica; you may choose any other thermally stable capacitor.

Receiver chassis is made using 4mm Flex-board. This can easily be cut, drilled and bent with hot-air gun. ELFY or quick drying glue can be used for joining various parts. Multi function power tool is best for cutting flex-board. Front panel is made by printing the panel design on an ordinary A4 paper; cutting it to size, getting it laminated and glueing.

 Collapsable rod antenna is adequate as  the receiving antenna. You may use about 2M extra wire for greater sensitivity.