KENWOOD KMC35
Instrukcja Serwisowa

KMC-35/36
CIRCUIT DESCRIPTION
Hot Microphone Function
In the Hot microphone state, only microphones whose PTT switch is pressed can send modulation signals in the environment in which several microphones are connected to the transceiver in parallel. In the Normal microphone state, if the PTT switch on one of the microphones is pressed, modulation signals are sent from all microphones.

� Circuit description
Hot microphone operation can be performed by cutting the jumper (JP1). If the jumper is not cut (Normal microphone state), bias voltage is always applied to the microphone element (Q3 is always ON) and if the microphone mute of the transceiver to which the KMC-35/36 is connected is released, modulation signals can be sent even when the microphone PTT switch is not pressed. If the jumper is cut (Hot microphone state), bias voltage is applied to the microphone element only when the PTT switch is pressed (Q3 turns ON only when the PTT SW is pressed), and modulation signals cannot be sent when the microphone PTT switch is not pressed.
5V

C17 100p

Q1 DTC114EUA
C14 1000p

R1 10k Q3 DTA144EUA

J1 1 BLC 2 SB 3 GND 4 PTT 5 ME(MIC GND) 6 MIC 7 HK(HOOK) 8 DM *L1 L2
PTT SW R9 1.5k C6 1000p

L3 L4 L5 L6 L7 *L8

R6 0

C20 1000p

Q2 DTC144EUA

R10 0

C7
S70-0499-08

1u 16
R2 10k

R8 1k

C9 10u 16 MIC
470p R7 3.9k R5 10k C11 R4 3.9k R3 10k JP1

E58-0475-05

C10 S1 0.068u

T91-0538-05

*C15

*C5

*C16 C12 1000p

*C19

C13 1000p C18 1000p

3