To power down the transceiver, press and hold the power button, and a message will be
displayed showing a count-down to zero. At this point the display will clear, the backlighting
will be turned off, and the button can be released.
During the count down period the current user settings are being written to the EEPROM. If
the button is released during the count-down, it will be aborted, and the previous operation
will be resumed.
During normal operation, a brief press of the power button will toggle locking the VFO
frequency. Note that this simply disables the VFO tuning knob, the receiver frequency can
still be changed by pressing either the VFO button or using the Rapid Band Switch feature.
The power button is also used to acknowledge and cancel any alarms. If an alarm cannot be
cancelled, then press and hold the power button for 500 mSec and you will enter the
emergency shutdown mode. Release the button and the transceiver will immediately shut off.
In this mode it will bypass saving the user settings in favour of a rapid power down. For full
details of the alarms, please refer to Annex F.
If the power button is pressed and held whilst powering up, the system setup menu will be
selected. The various operations and settings are fully covered in the System Setup section of
this document. To exit the setup menu without making any changes, press and hold the power
button to power the transceiver down.
CW Speed
This knob controls the speed of the internal keyer, or, can be used as a receiver squelch
setting. The operation of this knob is controlled by a setting in the User Configuration menu,
which is covered in the User Configuration section of this document.
MIC
The microphone/PTT switch is connected to this socket by means of a 3.5mm stereo jack.
The wiring is:
Tip
: Microphone/Line input
Ring
: PTT switch
Screen
: Ground/Shield
The PTT switch requires a dry contact closure to ground, or an open-collector connection
capable of sinking 0.5mA from +5V.
The microphone is normally expected to be an electret, and there is a bias voltage of +5V via
a source resistance of 5.7K. If a dynamic microphone is used, a DC blocking capacitor should
be wired in series with the tip connection. Most dynamic microphones have an impedance of
about 400Ω, for optimum speech quality and low frequency response, a capacitor of at least
2µF should be used. If using an electrolytic capacitor, wire the +ve to the tip of the plug.
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