Kenwood TS-990S - Manual (Page 273)

TROUBLESHOOTING 18
18-3
Index Contents
NOTICE CONCERNING INTERNAL BEAT
On some particular frequencies along the amateur
band an internal beat may occur due to the frequency
configuration. This is not a failure. Following are the
examples of the internal beat. (Frequency may vary
depending on the operating mode.)
In the following examples, "Main" represents the displayed
frequency of the main band, and "Sub" represents the
displayed frequency of the sub band. In some examples
the selected transmitting band is also a factor in
generating an internal beat..
INTERNAL BEAT OCCURRED IN THE MAIN BAND
• In combination of the main band range from 18.068 MHz to
18.150 MHz and the sub band range from 14.104 MHz to
14.350 MHz, and the transceiver transmits on the sub band.
Example: Main 18.100 MHz and Sub 14.200.28 MHz
• In combination of the main band range from 28.199 MHz to
28.765 MHz and the sub band range from 28.000 MHz to
29.700 MHz.
Example: Main 28.200 MHz and Sub 28.003.40 MHz
• In combination of the main band range from 50.753 MHz to
51.453 MHz and the sub band range from 14.000 MHz to
14.350 MHz.
Example: Main 50.760 MHz and Sub 14.004.97 MHz
• In combination of the main band range from 52.028 MHz to
53.361 MHz and the sub band range from 50.000 MHz to
54.000 MHz.
Example: Main 52.030 MHz and Sub 50.006.75 MHz
INTERNAL BEAT OCCURRED IN THE SUB BAND
• In combination of the sub band range from 3.769 MHz to
3.839 MHz and the main band range from 14.000 MHz to
14.350 MHz, and the transceiver transmits on the main band.
Example: Sub 3.775 MHz and Main 14.014.57 MHz
• In combination of the sub band range from 10.100 MHz to
10.150 MHz and the main band range from 1.852 MHz to
1.902 MHz.
Example: Sub 10.110 MHz and Main 1.862.00 MHz
• In combination of the sub band range from 7.000 MHz to
7.174 MHz and the main band range from 14.002 MHz to
14.350 MHz, and the transceiver transmits on the main band.
Example: Sub 7.050 MHz and Main 14.095.90 MHz
• In combination of the sub band range from 14.000 MHz to
14.350 MHz and the main band range from 28.500 MHz to
28.850 MHz.
Example: Sub 14.010 MHz and Main 28.510.60 MHz
• In combination of the sub band range from 21.000 MHz to
21.450 MHz and the main band range from 51.996 MHz to
52.446 MHz.
Example: Sub 21.010 MHz and Main 52.006.51 MHz
• In combination of the sub band range from 21.448 MHz to
21.450 MHz and the main band range from 14.000 MHz to
14.006 MHz, and the transceiver transmits on the main band.
Example: Sub 21.450 MHz and Main 14.005.52 MHz
• In combination of the sub band range from 29.248 MHz to
29.698 MHz and the main band range from 21.000 MHz to
21.450 MHz.
Example: Sub 29.250 MHz and Main 21.003.00 MHz
• In combination of the sub band range from 50.246 MHz to
51.246 MHz and the main band range from 1.800 MHz to
2.000 MHz.
Example: Sub 50.250 MHz and Main 1.802.21 MHz
• In combination of the sub band range from 52.634 MHz to
52.834 MHz and the main band range from 18.068 MHz to
18.168 MHz.
Example: Sub 52.640 MHz and Main 18.071.10 MHz
OTHER COMBINATIONS
The internal beat occurs while the transceiver receives,
using the sub band, on the frequency which has the first IF
frequency of 73.095 MHz. (Depending on the frequency of
the sub band, the internal beat may also occur on the sub
band.
Example:
• Sub 50.010 MHz and Main 28.298.28 MHz
SPURIOUS ON THE BANDSCOPE (WATERFALL)
A signal which has no correlation to the received signal
may appear on the bandscope (waterfall). This may occur
due to the frequency selection and is not a failure. The
spurious signal display may be reduced by adjusting the
attenuator and the reference level of the bandscope.
Example:
• The frequency which has ±24 kHz separation from the
receive frequency
• The frequency which has ±150 kHz separation from the
receive frequency
• (The spurious may differ depending on the receiving band or
the operating mode.)
• While the transceiver is receiving an internal beat