HIGH FREQUENCY AMPLIFIER DEVICE

摘要

PURPOSE:To reduce the deterioration in the gain at the reception of a high frequency band signal by coupling a cross point between a high frequency coupling coil and a choke coil and a cross point between a low frequency switching diode and a choke coil by means of a coupling capacitor. CONSTITUTION:The cross point between the high frequency coupling coil 110 and the choke coil 106 and the cross point between the low frequency switching diode 103 and the choke coil 105 are coupled by a coupling capacitor 107 and a signal is extracted from the cross point between the coupling coil 110 and the switching diode 104. A VHF band signal is outputted at the cross point between the diode 103 and the coil 105. The signal is fed to the next stage from a terminal 1E via the capacitor 107, a resistor 111 and the coil 110. On the other hand, a UHF band signal is affected by a stray capacitance 109, but since the inductance of the coil 110 is sufficiently larger than the UHF band signal, a stray capacitance 108 is shut from the signal path.