Ignition Sense Cable (Kct-18); External Speaker (Kes-4); Ignition Function; Timed Power Off Function - Kenwood TK-790 Service Manual

TK-790/ ( B

5. Ignition Sense Cable (KCT-18)

The KCT-18 is an optional cable to use the following func-
tions:

5-1. Ignition function

The ignition function allows you to turn the transceiver's
power on and off with the ignition key of your car. When
you are driving with the ignition key on, the horn alert func-
tion is disabled.

5-2. Timed power off function

The timed power off function turns the transceiver's
power off the time specified with the programming soft-
ware (KPG-44D) after the ignition key is turned off. When
you are driving with the ignition key on, the horn alert func-
tion is disabled.
The ignition sense function and the timed power off func-
tion can be used at the same time.
5-3. Modification
• If the TK-790 and KCH-10 or KCH-11 are used
1. Remove the short plug from the accessory connector (9
pins) on the back of the transceiver.
2. Insert the KCT-18 into pin 1 (IGN).
3. Remove the upper half of the case of the TK-790.
4. Set jumper resistors (0 ohm), R504, R506, R742 and
R743, on the control unit (X57-561 B/3) as shown in
Table 1 (Refer to page 21).
5. Reinstall the upper half of the case.
• When the remote kit is used
If the accessory connector (9 pins) on the rear of the
transceiver is available, use the method described above. (If
the KRK-7DB or KRK-8DBH is used, use the accessory con-
nector (9 pins) on the back of radio 1.)
If the accessory connector (12 pins) on the back of the
control head is used:
1. Remove the plug from the accessory connector (12 pins)
on the back of the control head.
2. Cut off the end of the rubber cap (accessory), insert the
KCT-18 into the cap, and insert it into pin 1 (IGN) of the
short plug.
3. Install the short plug and rubber cap on the connector on
the rear of the control head, then clamp the bottom of the
rubber cap with the supplied tie wrap.
4. Remove the upper half of the case of the TK-790.
5. Set jumper resistors (0 ohm), R504, R506, R742 and
R743, on the control unit (X57-561 B/3) as shown in
Table 1 (Refer to page 21).
6. Reinstall the upper half of the case.
Note : If the KCT-18 is used for the KRK-8DBH, use the 9-pin
plug on the back of radio 1 or the 12-pin plug on the back of
head 1. The plugs on radio 2 and head 2 cannot be used.
If the KCT-18 is used for the KRK-7DB, use the 9-pin plug on
the back of radio 1 or the 12-pin plug on the back of the
head. The plug on radio 2 cannot be used.
18
) /H ( B )
INSTALLATION
Available function when KCT-18 is
connected
Horn alert function OFF during
driving, Timed power off function
(Default)
Horn alert function OFF during
driving, Ignition function
None (The transceiver cannot be
turned on.)
HA function OFF during driving,
Ignition function & Timed power
off function
Table 1 R504, R506, R742 and R743 setup chart
(Refer to page 21)
Accessory
connector (12P)
1
10
Accessory
connector (9P)
1
7
3 KCT-18
9
Fig. 7

6. External Speaker (KES-4)

The speaker output from the TK-790 is as follows:
1. The KCH-10 has a built-in speaker (3W/8 ohms).
2. The KCH-11 does not have a built-in speaker.
3. The external speaker output from the accessory connec-
tor (9 pins) on the back of the transceiver is 13W/4 ohms.
Use the KES-4.
4. The speaker output from the accessory connector (12
pins) on the back of the control head is 2W/4 ohms. If the
remote kit (KRK-5, KRK-6DH, KRK-7DB or KRK-8DBH) is
used, use the KSP-1A or KES-4. If the KSP-1A is used, do
not attempt to modify the transceiver to increase the au-
dio output.
Note : Since the TK-790 uses a BTL audio amplifier, do not
ground the speaker output pin.
R504 R506 R742 R743
Present Absent Present Absent
Absent Present Present Absent
Absent Absent Present Absent
Present Absent Absent Present
3
Rubber cap
12
Tie wrap
Cut
KCT-18