Kenwood TS-890S In-Depth Manual page 20

03 TRANSMISSION CIRCUIT
● Tx Delay Time (CW/FSK/PSK)
For configuring the delay time that is enabled when in the CW/ FSK/PSK non-audio mode.
● Tx Delay Time (SSB/FM/AM)
For configuring the delay time that is enabled when in the SSB/FM/AM audio mode.
This can be configured to a setting that is different from that for the non-audio modes.
When PTT is pressed, the sound that is emitted from the PTT switch as well as the operating sound of linear amplifier
relay switching may sometimes be picked up by the microphone and transmitted. In such a case, the delay time can be
configured to a longer duration to prevent output of unwanted radio wave transmissions.
● Internal Relay Control
For configuring whether to activate the built-in linear amplifier control relay.
The rated control capacity of the relay contact is 2 A/30 V DC (resistance load) and the maximum allowable voltage is
220 V DC and 250 V AC. It can be used to switch high-voltage signals such as those of a vacuum tube linear amplifier.
Control of the TL-922 (terminal voltage: -140 V) is possible.
● External ALC Voltage
For use with a linear amplifier or transverter, it is possible to connect an external device to the ALC terminal (pin 6) to
enable proper transmit power control.
The External ALC Voltage can be configured to -1, -2, -3, -4 (default setting), -5, -6, -7, -8, -9 or -10 (V), and the internal
gain starts to decrease upon roughly reaching the preconfigured voltage.
When the linear amplifier that is being connected supports full break-in and is placed in the transmitting state when a
voltage of +12 V is applied, configure "Keying Logic" to "Active High" and "Internal Relay Control" to "Off".
If the external linear amplifier that is being connected does not support full break-in and takes time to switch the internal
relay contacts, such as the TS-922, configure to "Tx Delay Time (CW/FSK/PSK)" or "Tx Delay Time (SSB/FM/AM)" in the
linear amplifier menu. This configuration extends the duration of time from when the transceiver is placed in the transmit
state until radio waves are practically transmitted so that the linear amplifier relaying will switch and then transmit the
radio waves. If full break-in is active in CW mode, the duration of time prior to a transmission is not extended.
Note that configuring to "Tx Delay Time (CW/FSK/PSK)" or "Tx Delay Time (SSB/FM/AM)" extends not only the duration
of time until a transmission starts but also the duration of time until reception begins, and this helps to reduce the click
noise at the moment of switching to reception.
Fig. 17 Linear Amplifier Control Settings Menu Screen
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