User & Installation manual
VHF- Communication Transceiver
Doc.-Nr.:
DE-3000-800100e
KRT2, KRT2M, KRT2RC
Revision 13.0
Jul. 2016
44 / 67
6.6.2 Speaker & open microphone:
An installation with open microphone together with a speaker and intercom
is not possible.
Running a speaker together with an open microphone (goose neck) the
Intercom operation hast to be turned off by setting VOX=10 or opening the
intercom switch (indicatin
g “e”) otherwise a feedback from the speaker will
occur.
6.6.3 Earphone Connection
Several earphones of same type can be connected in parallel. The total
impedance should not be less than 60 Ohms.
6.6.4 External Audio Input
Audio alarms can be made available via the external audio input. When
this input is not used it must be connected to ground in order to avoid
noise. PIN5 must be connected to ground (GND).
6.6.5 Speaker Connection
The high output power for the speaker requires a differential
interconnection.
This does not allow for one side of the speaker wires to be grounded.
Both the wires have to be installed fully insulated.
Special intention has to be paid off at gliders after retrofitting on older
installations. Check with a meter the resistance between one of the
speaker wire and the case of KRT-2, it should be at high impedance.