Onwa KR-1338, Service Manual

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2.3 Transceiver Unit
MIC
The following description is for reference only.
As a general rule of thumb, the radar requires better noise figure (NF) and better
dynamic range. Both factors, however, are reciprocal. The NF affects long range
performance, while the dynamic range dose short range performance.
To improve noise figure, amplifier and MBS circuit into the MIC, RU-9360.
MIC w/RF amplifier NJT-1968B(MODEL 1338/1668)
IF OUT
(+5V to 35V) (+5V) GND
RF IN
W.G.TO
COAX CONV.
LIMTER FET AMP
DOUBLE-
BALANCED
MIXER
POWER FET OSC.
Block Diagram of MIC NJT-1968B (MODEL 1338/1668)
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