Kenwood TKR-851 Service Manual page 21

Fine-Tuning the TKR-851
"ADJUSTMENT" items described in the Service Manual
for the TKR-851 give the factory-default adjustment proce-
dure covering all adjustment items.
However, it is not necessary to adjust all the items when
adjusting the power, deviation, receiver sensitivity, etc at the
frequency of the channel to be used by the TKR-851.
Adjustment procedure at the frequency of the
channel to be used
1. Program a channel frequency using the FPU (KPG-91D).
2. From the FPU menu, select in the order of "EDIT", "Test
Frequency" and "CH paste" to rewrite the test frequency
from the factory-default to the one to be used for the
channel.
Erase all channel frequencies rewritten through this op-
eration and press the ENTER key to retrieve the factory-
default test frequency.
Alignment
Item Condition
1. Setting 1) Connect the unit to a suitable DC power supply.
1) Turn the DC source switch on after connecting a PC and FPU cable to the radio. → "E1" appears on LED display
2. Write test
frequency 2) Write the test and shipping frequency to the radio.
3) End of test frequency writing.
3. Setting 1) Connect the unit to a suitable DC power supply.
2) Turn the power switch on after connecting a PC and FPU cable to the radio.
3) Start up the program for the adjustment.
4. RX PLL lock 1) RX VCO A high
voltage CH : 11 K
CH : 10 K2,M2,E,E3
2) RX VCO A low
CH : 10 K
CH : 1 K2,M2,E,E3
3) RX VCO B high
CH : 3 K,K2
CH : 11 M2,E,E3
4) RX VCO B low
CH : 5 K
CH : 6 K2,M2,E,E3
5. TX PLL lock 1) TX VCO high
voltage CH : 3
2) TX VCO low
CH : 1
6. RX 1) Connect the frequency
frequency counter to CN3, then
measure the frequency
CH : 2
Note : RX frequency means the local frequency of the RX VCO. So its frequency is wanted frequency minus the IF frequency.
ADJUSTMENT
Refer to the explanation given under HELP for the FPU
(KPG-91D) for details.
3. Check whether the frequency rewritten under the "Test
mode" of the FPU (KPG-91D) is correct, then select the
item to be adjusted from the FPU (KPG-91D) menu and
adjust the set value for the item to an optimum value with
the "TEST" tag.
Note :
After adjustment of the "Max. Deviation", be sure to
check the "DQT balance".
Performs adjustment of "5-tone signaling" at E,E3
and M2 markets.
Perfoms the adjust of "Wide 4k" only the product of
the E market code, does not do the product of the E3
market code.
Measurement
Test-
Unit Terminal Unit
equipment
DVM TX-RX RX-CV RX VCO TC350 1.50V
(A/2) (A3)
RX VCO TC351 1.50V
(A3)
TX-CV TX VCO TC350 1.50V
(A2)
f. counter CN3
TKR-851
Adjustment
Parts Method
→ Green (BUSY) LED lights up
± 0.1V
Check 8V or less
± 0.1V
Check 8V or less
± 0.1V
K,K2,M2,E
TC351
E3
Check 8V or less
PC adj. 50Hz or less
Test CH–44.85MHz
Specifications/Remarks
21