TR850 Service Manual
When AC power supply is off, the electric relay (U1) is released. The DC is connected to U2 via the
electric relay (U1) contact. If the panel switch (J5) is on, the electric relay U2 will be switched on, so is the
repeater.
The panel switch (J5) is off, and U2 is released, which cut off the baseband DC power supply B13V
including the RF power supply R13V.
Over-voltage Protection
Figure 3-9 Over-voltage Circuit Protection
As the Figure 3-9 shows, the breakdown voltage of the voltage stabilizing diode is 18V+/-0.5V. If the input
DC volatage is over 18V+/-0.5V, the Q1 breaks over with Q2 being cut off, and the electric relay U2 will be
released to cut off the DC power supply B13V, including the RF power supply R13V.
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Summary of Contents for TR850
Page 1: ......
Page 45: ...TR850 Service Manual 5 4 Connection 1 2 3 4 6 8 7 5 9 10 13 14 15 16 18 17 11 12 41 ...
Page 90: ...TR850 Service Manual Figure 1 Rx Module Top Board PCB View 86 ...
Page 91: ...TR850 Service Manual Figure 2 Rx Module Bottom Board PCB View 87 ...
Page 93: ...TR850 Service Manual Figure 5 Power Amplifier Module Bottom Board PCB View 89 ...
Page 94: ...TR850 Service Manual Figure 6 Baseband Mainboard Top Board PCB View 90 ...
Page 95: ...TR850 Service Manual Figure 7 Baseband Mainboard Bottom Board PCB View 91 ...
Page 97: ...TR850 Service Manual Figure 10 Power Board Top Board PCB View 93 ...
Page 114: ...TR850 Service Manual Figure 16 Baseband Mainbaord Schematic Diagram 110 ...
Page 169: ...TR850 Service Manual Figure 1 Rx module Top Board Position Mark Diagram 165 ...
Page 170: ...TR850 Service Manual Figure 2 Rx Module Buttom Board Position Mark Diagram 166 ...
Page 172: ...TR850 Service Manual Figure 5 Power Amplifier Module Buttom Position Mark Diagram 168 ...
Page 173: ...TR850 Service Manual Figure 6 Baseband Mainboard Top Board Position Mark Diagram 169 ...
Page 174: ...TR850 Service Manual Figure 7 Baseband Mainboard Buttom Board Position Mark Diagram 170 ...
Page 176: ...TR850 Service Manual Figure 10 Power Board Top Board Position Mark Diagram 172 ...
Page 193: ...TR850 Service Manual Figure 16 Baseband Mainboard Schematic Diagram 189 ...