Kenwood TKR-D710 Service Manual page 49

The display indicates "E 3 "
The display indicates "E 5 "
The display indicates "E.6. "
The display indicates "E 6. "
The display indicates "E 6 "
Priority level of display
2. If normal power is not obtained, please
follow the steps below
1. Switch off the repeater.
The impedance of the Final FET (Q4) and Drive FET (Q3)
can be measured easily using a DVM (Digital Volt Meter)
ohm mode.
Normal condition – Gate: > 50kohm
The above impedance values are rough estimations.
2. Switch on the repeater. Check the voltage at F1 output
point.
The voltage is around 13.6V during reception.
The voltage will be 13.2V~ during transmission.
If this point measures 0V, then F1 is damaged.
3. Remove C24.
TROUBLE SHOOTING
4. Connect a 50ohm load to the ANT terminal.
Transmit and check the current drain in High power
mode.
If the current drain is less than 1.0A, then the Final FET
is damaged.
If the current drain is less than 5.0A, short the Drive FET
gate to ground, and check the current drain.
If the current drain is not 0.1A less than the original val-
ue, then the Drive FET is damaged.
5. Check the input power level at the Drive FET gate loca-
tion.
Connect the wire to [RF] location. (A join of R23 and R24)
Confi rm that it is about 0.1W.
If power found is considerably lower than 0.1W, check
the circuit before the Drive FET.
TKR-D710
Appears when TX PLL or RX PLL is Un-Lock.
TX LED blinks at TX PLL Un-Lock.
BUSY LED blinks at RX PLL Un-Lock.
This display disappears when PLL is steady.
However, the following cause might exist when not
disappearing for a long time.
(At the setting that uses External reference.)
Please Input an "External reference" signal,
or change the FPU setting.
Please reactivate the Repeater.
Appears when the ESN is not written to the repeater.
Please write the ESN.
or writes. The DSP may be broken.
E.6. E6 E6. E5 E1
E2 E3
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