LDG Z-817H Operation Manual - page 12
PAGE 12
Finishing Up FT-817 Installation
If it is desired to operate the FT-817 via computer control, connect a Yaesu CT-62 cable (not
supplied) to the jack on the Z-817H marked “
PC
”. The Z-817H will automatically feed through
any CAT commands coming in over this port to the transceiver and vice versa. Note that any
software used to control the transceiver will have to be set for 38,400 baud while connected
through the Z-817H.
Hookup For Radios Other Than FT-817
If using the Z-817H tuner with a radio other than a Yaesu FT-817, the hookup is the same as
for use with the FT-817 (with or without amplifier), but the CAT radio interface cable is not
used. Tuning operation with a non-FT-817 radio is slightly different; see the section on
Using
The Z-817H With Other Radios
.
OPERATION
Power-up
The Z-817H is powered by internal batteries. Each time the
TUNE
button is pressed, the Z-
817H first checks the connection to the transceiver. If an FT-817 radio is detected, the
SWR
LED will flash briefly before continuing on with normal operation. If an FT-817 radio is hooked
up, but the SWR LED does not flash briefly each time the
TUNE
button is pressed, then the Z-
817H has not properly detected the attached radio.
Possible causes for failure to detect the radio properly are: an improperly seated CAT cable,
a damaged CAT cable, incorrectly selected CAT baud rate, FT-817 not turned on, or plugging
the CAT cable into a radio other than an FT-817. If checking all of these things does not correct
the situation, try turning the radio off and back on again.
Basic Tuning Operation, Using With The FT-817 Radio
The Z-817H is operated from the front panel
TUNE
button on the Z-817H. Two types of
tuning cycles are available; a memory tuning cycle and a full tuning cycle.
The
memory tuning cycle
attempts to tune quickly based on having previously tuned on the
present frequency selection. If the tuner previously was successful in tuning on the currently
selected frequency, the settings for that match will be loaded into the tuner relays, and checked to
see that an acceptable SWR match is found.
A
full tuning cycle
“starts from scratch” and begins a fixed tuning sequence where the Z-
817H rapidly tries varying combinations of inductance and capacitance values, and then zeroes-
in on the best match possible. When the tuning cycle is complete, if an acceptable match was
found, the inductance and capacitance settings are saved in a memory associated with the
selected frequency, so that they may be recalled quickly in the future via a memory tuning cycle.
In this manner, the Z-817H “learns”; the longer you use it, the more closely it adapts itself to
the bands and frequencies used. Most users will probably use memory tuning most of the time; it
takes advantage of any saved tuning settings, but automatically defaults to a full tuning cycle if
no stored data is available.
In both cases, at the end of the tuning cycle, the carrier is held for 1.5 seconds after tuning is
complete, so that the final SWR may be read on the transceiver’s internal SWR meter or another
inline SWR meter, and the front panel LED will indicate the status of the tuning cycle.