Operation and Installation Manual
KRT2 VHF-Communication Transceiver
Doc.-No: KRT2.A-MAN.en
Rev. 0101
Page
24
Menus L and R:
By means of the turning knob the displayed microphone input channel amplifier gain (MIC-level 01 =
low gain, 09 =high gain) can be selected individually. The microphone signal level is dynamically dis-
played with a bar and a numeric value.
The initial MIC-level should be 0,5; the engine should be running, use a headset or earphone and
speak at a normal voice level to fine-tune the MIC-level. Whenever a new MIC level is selected, the
dynamic bar indicator should then be at about 50%.
Special hint:
During MIC-Setup activation, the speaker state will be taken into account (SQU on/off),
if the state is active an acoustic feet-back may be heard.
The range of the MIC-level for standard microphones is 1 to 9.
MIC levels 10 and 11 are special settings for low microphone levels like dynamic micro-phones often
used in gliders.
•
Level 10 is used for non-amplified Electret microphones with an 8 volt supply voltage.
•
Level 11 is for dynamic microphones only.
For high gain selection (> 9) the use of side tone can lead to a feed-back at transmission. In that case
the side tone should be set to SIT=01.
The new values will be stored upon exiting the microphone setup menu. AUTO must be selected in
order to activate the AUTO menu, else use L or R to activate the Left and & Right microphone menu.
Menu Auto
In the AUTO mode only the left microphone impedance is measured. When a dynamic microphone is
recognized, the left channel is switch to 11, the right channel is unaffected. When returning to the
standard configuration, the original L and R values are restored.
A simultaneous operation on Electret and Dynamic microphones is not possi-
ble (there is just one DC source for both ports). For dynamic mode this source
must be turned off automatically.