home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
World of Ham Radio 1997
/
WOHR97_AmSoft_(1997-02-01).iso
/
mods
/
kenwood
/
asb_text
/
asb0976.txt
< prev
next >
Wrap
Text File
|
1997-02-01
|
3KB
|
76 lines
==============================================================================
K E N W O O D
>>> A M A T E U R R A D I O S E R V I C E B U L L E T I N <<<
==============================================================================
Kenwood Service Centers
Kenwood Service Corporation Kenwood Service Center, East
2201 East Dominguez Street 829 Lynnhaven Parkway, Suite 130
Long Beach, California 90801 Virginia Beach, Virginia 23452
Telephone 1-310-639-5300 Telephone 1-804-340-1702
==============================================================================
BULLETIN # 976
MODEL: TH-26A
SUBJECT: INTERNAL BIRDIES
The TH-26A has two internal birdies. One is at 145.645MHz and the other
is at 147.200MHz. The first one is caused by the CPU clock and the second
one is caused by the PLL reference crystal. The birdie related to the CPU
clock can be corrected by changing R78 on the Control board from 3.9K ohm
to 6.8K ohm and adding a ground to R64. The birdie related to the reference
crystal can be corrected by changing L12 on the TX/RX (B/2) board from a
10uH inductor to a 1mH inductor.
REQUIRED PARTS:
RK73GB1J682J 6.8K OHM CHIP RESISTOR
L40-1021-14 1mH INDUCTOR
TO CHANGE R78:
1. Disconnect the battery pack and antenna.
2. Remove the three case screws and four battery plate screws. Figure 1
3. Lift the front panel from the body of the transceiver.
4. Do not lose the rubber cover for the DC IN jack.
5. Locate R78 on the Control board inside the front panel. Figure 2
6. Replace R78 with a 6.8K ohm chip resistor.
7. Install a jumper wire from R64 to the mounting plate behind the
PTT switch. Figure 2
TO CHANGE L12:
8. Remove the four screws from the TX/RX (A/2) board. Figure 3
9. Carefully lift the TX/RX (A/2) board up and rotate it and the front
panel assembly to the right of the transceiver.
10. Do not lose the rubber cover for the SPEAKER/MIC jacks and the plastic
piece from the battery release.
11. Remove the two screws from the power module shield and set the screws
and shield aside. Figure 4
12. Remove the four screws from the TX/RX (B/2) board. Figure 4
13. Remove the three black screws from the back panel that secure the
antenna BNC connector.
14. Carefully lift the TX/RX (B/2) board off the back panel.
15. Locate L12 on the TX/RX (B/2) board. Figure 4
16. Replace L12 with a 1mH inductor.
17. Assemble the transceiver.
Time required to perform this modification is 1 hr. or less.