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PTT TAB
DIGI KEYER II has three (3) PTT outputs: PTT, PA PTT and LNA PTT. PTT is brought out to the DB15 Radio
connector. PA PTT and LNA PTT are available on RCA connectors at the DIGI KEYER II rear panel.
PTT is normally wired to the radio Accessory jack and is
used to switch the radio into transmit.
PA PTT is present at the DIGI KEYER II 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
time selected for PTT Lead tail and will open at
the same time as the transceiver PTT.
LNA PTT is present at the DIGI KEYER II rear panel
RCA jack
and
is
designed for switching
(bypassing) a low noise preamplifier (LNA)
during transmit.
LNA PTT is enabled by
checking the LNA PTT box.
LNA PTT will close before the transceiver PTT
by the time selected for PTT Lead and and will
open after the transceiver PTT by the time
selected for LNA PTT Tail.
PTT output generally folows the PTT inputs (PTT port, PTT In, Soundcard PTT and WinKey PTT). However,
PTT behavior is configurable in CW Mode.
CW options are:
PTT (normal operation),
QSK (no transceiver PTT, PA PTT has no
release delay), and Semi Break-in (no
transceiver PTT, PA PTT includes release
delay).
PA PTT: Enables PA PTT
LNA PTT: enables NA PTT
Sound card PTT: Enables automatic PTT when the
sound card has been “opened” for output by
the operating system.
PA PTT tail: delay between release of transceiver
PTT and PA PTT.
LNA PTT tail: delay between release of transceiver PTT and PA PTT.
Invert: when checked, LNA PTT sense is reversed (closed in receive).
PTT lead: delay between closing PA PTT/LNA PTT and Transceiver PTT/CW output.
PTT tail: how long the transceiver PTT is remains closed following the last CW element. PTT tail can be a fixed
length from 10 to 2500 ms or proportional to the CW Speed.
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