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PTT OUTPUTS
MK2R has four (4) PTT outputs for each radio: PTT1, PTT2, PAPTT and LNA PTT. PTT1 and PTT2 are
brought out to the DB37 Radio connector. PAPTT and LNA PTT are RCA jacks for connecting to external
devices.
PTT1 is wired to the radio microphone
jack and is normally used to
switch the radio into transmit in
VOICE and CW mode.
PTT2 is wired to the radio Accessory
jack and is used to switch the
radio into transmit in DIGITAL
and FSK modes.
Note: PTT2 or "rear panel" PTT
is used by some radios to
automatically mute the
microphone and disable
microphone processing circuits
(audio equalizers, transmit
DSP, compression, clipping,
etc.) that can distort digital
modulation.
PA PTT is available at the MK2R rear
panel RCA jack and is designed
for switching a power amplifier.
PA PTT is enabled by checking
the PA PTT box. PA PTT will
close before transceiver PTT by
the amount of selected PTT
Delay and will open at the same
time as the transceiver PTT.
Note: PTT delay should be a
few milliseconds longer than the
T/R delay of the amplifier.
LNA PTT is available at the MK2R rear panel RCA jack and is designed for bypassing a low noise
preamplifier (LNA) or disabling receive antennas during transmit. LNA PTT is enabled by checking
the LNA PTT box. LNA PTT leads the PTT1 and PTT2 by the PTT Delay value and opens after the
transceiver PTT by the same amount.
ENABLE is an optional signal available on the ACC jack. Enable may be used to prevent RF output until
the amplifier and/or LNA switching is complete, on transceivers that support inhibit.
MK2R can independently select the active PTT output for each transceiver based on the mode, and
optionally frequency, reported by the transceiver in response to polling by the application (logger) and/or
Router. If Router is not able to read the operating mode from your radio (radio does not have computer
control port or does not report usable mode information), you can select one of four fixed “no radio” modes
or one “no radio” mode with manual (keyboard/keypad) mode selection.
Router recognizes four operating modes for the radio: CW, VOICE, DIGITAL and FSK (RTTY) with three
selections for PTT: CW, Voice and FSK/DIGITAL.
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