Kenwood TS-900 Operating Manual page 35

5.11 VOX-MKR_= (VOX-Marker)
BOARD (X54-1020-10) (See Figure 30)
VOX CIRCUIT
The VOX circuit amplifies the audio input and the AF
output, and controls transistor Q8 which drives the T/R
relay. When the stand-by switch is in the SEND position,
Q7 is turned off and Q8 is turned on. Turn VR1 to adjust
the time constant of the circuit. Transistor Q5 controls the
time constant of the circuit.
MKR CIRCUIT
To calibrate the TS-900, transistor Q12 pulls a harmonic ta t Joc oaiile o |
frequency component from the 100 KHz crystal oscillator. j ie rt
When the MS terminal is grounded, Q10 and Q11 divide the
ANTI VOX
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VOX -MKR Unit (X54-1020-10)
FIGURE 31. VOX-MKR Schematic