The transition from reception to transmission by VOX-switch, made by transistors VT2/VT3 (KT315). Kodensator Cl – 0,5-2,2 pF, establishes a reliable operation of the relay Kl.

Inductors L6 – L8 made wire of 0.4 mm, L6/L7 -6 turns, L8 – 100 turns. High-frequency coil wound around a silver-plated wire of 0.8 mm: Ll – 2 turns, the frame – 8 mm, the winding length of 11 mm; L2/L3 – 4 turns, the frame – 6.8 mm, the winding length of 10 mm; L4/L5 – 5 turns, the frame – 5.2 mm, the winding length of 12 mm.
Output impedance 75 ohms cascade. Capacitor C4 provides from 33 to 180 pF.

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