In this circuit of the 1980s, the T1 transformer has 30 turns of 28 primary wire and the secondary 4 turns. The circuit works up to about 30 MHz. The integrated circuit is rare today.

In this circuit of the 1980s, the T1 transformer has 30 turns of 28 primary wire and the secondary 4 turns. The circuit works up to about 30 MHz. The integrated circuit is rare today.