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TRC-70
CIRCUIT DESCRIPTION
BPF NO. | Frequency (MHz)
Bi
0.1~1.5999
B2
1.6~2.9999
B3
3.0~4.9999
B4
5.0~6.9999
BS
7.0~8.9999
B6
9.0~13.9999
B7
14.0~17.9999
BS
18.0~29.9999
Tabie 5 Receiving bandpass bilter table
¢
Squelch circuit
¢
Noise blanker (NB) circuit
The input of the NB circuit is extracted from the
outputs of second-stage RX mix FETs Q13 and Q14
(2SK520(K44)) and is applied to the NB hybrid 1C1
(KCX01). The input signal is amplified and detected by
IC1 then output as a noise blanking signal. The opera-
tion of IF arnplifier Q15 (83SK131(M)) is stopped by NB
switching transistor Q16. Noise components are then
eliminated.
NB1 is used for short-duration pulses such as igni-
tion noise.
NB7 is used for longer-duration, long dura-
tion pulse noise such as the woodpecker.
Transmitting Circuit Configuration
19
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