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3-2

• BPF TABLE

• While operating on the 144 MHz and 430 MHz bands

The RX signal from the antenna connector ([ANT2]) is passed

through the power/SWR detect circuit (D651 and D661) and

LPF (L591 to L593, C591 and C592).

144 MHz BAND SIGNAL

The RX signal is passed through the LPF (L541 to L543,

C542 to C547) and TX/RX SW (RL531).

When the attenuator is turned ON, the RX signal is also

passed through the 20 dB attenuator (D551 and D552).

The RX signal is then passed through the BPF (MAIN UNIT

: D553 to D556, L552, L553 and C553) and applied to the

pre-AMP (Q551).

The ampliﬁ ed signal is passed through another BPF (MAIN

UNIT: D557 to D560, L557 and C561), RX mute (D181 and

D182), BPF (MAIN UNIT: D3272, L3271, L3272, C3271 to

C3273) and LPF (L3261 to L3263, C3261 to C3267), and

then applied to the 1st RX IF circuit.

430 MHz BAND SIGNAL

The RX signal is passed through the HPF (L441, L442, C441

to C443), mute SW (D433 and D434) and TX/RX SW (D422

to D424).

When the attenuator is turned ON, the RX signal is also

passed through the 18 dB attenuator (D451 and D452).

The RX signal is then passed through the BPF (MAIN UNIT

: D454, L452 and C454) and applied to the pre-AMP (Q451).

The ampliﬁ ed signal is passed through the 2-staged BPF

(MAIN UNIT: D455, L453, C468 and D456, L454, C473), and

applied to the RF AMP (Q481).

The ampliﬁ ed signal is passed through the RX mute (D181

and D182), BPF (D3272, L3271, L3272, C3271 to C3273)

and LPF (L3261 to L3263, C3261 to C3267), and then ap-

plied to the 1st RX IF circuit.

Filter

Operating frequency

(MHz)

Filter switches

Components

Control line

(Active High)

B0 0.030000 to 1.599999 D3111 D3112 L3112, C3112, C3113, C3115 B0

B1 1.600000 to 1.999999 D3121 D3122 L3103 to L3106, C3102 to C3106 B1

B1 and B2 2.000000 to 3.399999 D3121 D3122 and D3131 D3132