Kenwood TS-950S Service Bulletin

Service Bulletin
Division
Subject:
TS-950S/SD TX IMAGE ON 18.115MHZ
Some TS-950SD owners have reported a transmit image at
18.115MHz that
distortion on the carrier. If the operating frequency is
shifted 3KHz
disappears. This modification will lower the image level
from -30dB
installing a trap on the 455KHz I.F.
REQUIRED PARTS:
4pF TRIMMER CAPACITOR
40pF TRIMMER CAPACITOR
2.2uH COIL
MODIFICATION:
1. Disconnect the power cord and antenna.
2. Remove the top and bottom covers (18 screws).
3. Locate
transceiver. This is the back right board of the 4
boards on the bottom of the transceiver. Figure 1
4. Locate L36
Figure 2
5. Install
capacitor across L36. Figure 3
6. Install a 2.2uH coil and 40pF trimmer capacitor in
series from the output of L36 to ground. The can of
L31 can be used for ground. Figure 3
ALIGNMENT:
1. Connect the TS-950S/SD to a power meter and 50 ohm
load.
causes the
above or
(worse case)
the I.F. board
by connector
and solder
Date: 02/06/91
receiving
below 18.115MHz,
to better
C05-0308-05
C05-0309-05
L40-2292-14
on the
CN17 on
into place
ASB-982
Amateur Radio
station to hear
the image
than -40dB
bottom of
the I.F. board.
a 4pF trimmer
by
the