Kessler AT-AUTO Operating Manual page 22

External Tuner Handshake
For those Icom and Kenwood radios that provide for control of external tuners, the AT-
AUTO is designed to utilize the transceiver's external tuner interface. This is normally via
(tm)
a button on the transceiver labeled, TUNER. During Automatic mode operation, whenever
the radio's TUNER button is depressed, the radio signals the AT-AUTO
tuner) which then automatically coordinates with the transceiver to produce a CW carrier for
tuning. The net effect is that the amount of time that the transceiver is required to produce
a carrier for tuning is greatly reduced, thereby minimizing potential for QRM. Here is how
it works: When the operator presses the TUNER button on the transceiver, the transceiver
signals the AT-AUTO
transceiver to produce a 10W CW/FM carrier at which time the AT-AUTO
the SWR and counts the frequency. This process takes approximately
SWR exceeds the "Tune Start SWR" threshold, the AT-AUTO
settings for the Capacitor and Inductor from memory and positions them accordingly.
Once the positioning of L and C are complete, the AT-AUTO
transceiver to produce the 10W CW carrier. If the SWR is still excessive, automatic tuning
begins. The moment a good match is found, the AT-AUTO
cease transmitting and the AT-AUTO
When using Smart QSY and External Tuner Handshake modes together, the entire au-
tomatic tuning process is greatly streamlined. As the user returns to previously-matched
frequency/antenna combinations, the AT-AUTO
matched settings, without requiring an RF carrier, and often without requiring subsequent
re-tuning.
Note: External Tuner Handshake is implemented for Icom and Kenwood radios only.
Fine Tuning
There will be occasions, when the SWR is well below the "Tune Start SWR" threshold, but
the operator may wish to improve the match. This may occur when the operator decides to
QSY away from the previously matched frequency, but remain in the same band. Rather than
repositioning L and C positions from memory, all that is required is for the AT-AUTO
to perform fine adjustments of L and C from their present positions.
Fine Tuning is commanded by momentarily pressing the Tune-Select rotary knob, when
in Automatic mode. If the AT-AUTO
with the transceiver, the entire fine tune process will complete automatically without further
intervention (presently only Icom radios support this feature), and the new match settings
will be stored in the AT-AUTO
If External Tuner Handshake is not established, the AT-AUTO
that tuning is requested. The AT-AUTO
(tm)
(tm)
has been configured for External Tuner Handshake
(tm)
memory.
(tm)
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(tm)
automatically stores the match settings.
precisely recalls and returns to those
(tm)
(the external
(tm)
then signals the
(tm)
samples
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1
second. If the
2
then recalls appropriate
(tm)
again signals the
(tm)
signals the transceiver to
will prompt the oper-
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14
(tm)