Operation Manual

Page 10 VL-1000 Operating Manual
Operation
Preliminary Checks
Before switching on power, recheck all in-
terconnections. Be certain that the ground, RF
input, and ALC connection cables are all se-
cure.
If using a Yaesu FT-980 transceiver for ex-
citation, set the L
IN AMP switch on the rear panel
to the (upper) Position 1. If using an FT-
757GX(II) or FT-767GX, ensure that the L
IN or
L
INEAR switch is depressed (Position 1). Other
Yaesu transceivers do not require special
switch setting on the transceiver prior to com-
mencing amplifier operation
Band Changes
By now, you have noticed that there is no
“B
AND” switch on the VL-1000. Selection of the
frequency band is accomplished in one of two
ways:

If using a Yaesu transceiver with a BAND
DATA control cable, band selection and an-
tenna rematching will occur automatically
whenever you change bands on the trans-
ceiver. Similarly, the antenna last used by
the VL-1000 on each band will be reselected
when that band is recalled on the trans-
ceiver.

If you are using a transceiver without a band
control cable, injecting a carrier from the
exciter for few seconds causes the VL-
1000’s microprocessor to count the input
frequency and automatically set the ampli-
fier up for operation on the appropriate band.
Here are the appropriate procedures:
1. Set the M
ODE switch of the exciter to CW,
and the D
RIVE or RF PWR control of the
exciter so as to provide 50 Watts of less
of drive power to the VL-1000.
2. Press the F SET key on the VL-1000 mo-
mentarily, then press the P
TT switch of
the exciter to activate the transmitter. If
necessary, close your key to allow a car-
rier to be transmitted for a few seconds.
3. The microprocessor of the VL-1000 will
now detect the frequency of the input sig-
nal, and the amplifier will then set itself
to the matching band.
4. When the correct band appears on the
VL-1000 display, release the exciter’s
P
TT switch so as to return to the receive
mode. Preliminary band setup is now
complete.
If you attempt to transmit on an improper
band (for example, at 6.2 MHz), the VL-1000
will automatically be placed in the “THRU”
mode, and no amplification will take place.
Antenna Selection
Pressing the ANT switch repeatedly causes
the VL-1000 to “toggle” between the rear panel
antenna jacks. Just remember to select the
correct antenna when making band changes
during initial operation, and the VL-1000 will
thereafter remember which of ANT 1 through
ANT 4 should be selected when you return to
that band.
When the amplifier is turned off, the default
antenna selection is ANT 1. You may wish to
consider putting a grounding-type coaxial
switch in the coaxial line connected to the ANT
1 jack, so as to shunt static electricity or nearby
lightning pulses to ground.
Fan Operation
The cooling fans for the amplifier and power
supply are both thermostatically controlled. The
thermostats are set to activate well before “dan-
gerous” heat has built up inside the cabinets.
It is quite normal for the fans to cycle on and
off, occasionally, even during receive opera-
tion. The fans also may continue to operate
after the front panel power switch is turned off,
this feature allows the complete dissipation of
heat so as to ensure long life of the compo-
nents.
Important Note
The VL-1000 requires input drive power of
50~60 watts. Please ensure that the trans-
mitter used with this amplifier is capable of
producing at least 60 Watts of drive power
so as to ensure full output from the VL-1000.
When driving the VL-1000 with a transceiver
which includes a built-in antenna tuner,
please turn the transceiver’s antenna tuner
off when using the VL-1000.