I found this circuit in a 1980 publication. Originally it was created to have a fixed tuning, but it can be converted to variable tuning by exchanging C2 for a common variable capacitor. L1 consists of 80 turns of wire 28 in a ferrite rod and transistors Q2 and Q3 can be replaced by BC548 and BC558. The circuit is connected to the input of an amplifier and has a very low consumption. Q1 can be the BF245.
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