AL-800H Instruction Manual
1
Features
•
The AL-800H uses two reliable
high gain 3CX800A7
tubes
.
•
A
time-delay circuit
provides a 180 second warm-up to eliminate potential damage to the tube
cathodes.
•
A
grid overload circuit
quickly disables the amplifier if the grid current becomes excessive. This
feature prevents excessive grid current from causing distortion or damaging the tubes or other
components.
•
A
thermal overload
automatically disables the amplifier if excessive heating of the power transformer
occurs.
•
A
multi-voltage heavy-duty transformer
with a unique "buck-boost" winding allows adjustment of
the primary voltage to 14 different voltages centered on 115 and 230 volts. This versatile Ameritron
feature allows the user to select the optimum primary voltage for maximum performance and life.
•
The tuning and loading controls have
vernier 6:1 reduction
drives for smooth tuning. Logging scales
allow quick and repeatable control adjustment for rapid band changes.
•
The AL-800H has two
illuminated cross-needle panel meters
. the left meter provides a continuous
reading of grid and plate currents. the right meter reads peak RF power output on one scale and Plate
voltage (HV), Reflected power and SWR (REF), ALC detector voltage (ALC), and ALC adjustment
level (ALC SET) on the other scales.
•
Heater and plat voltages are maintained using the
"STBY/OPR"
switch. This allows the amplifier to
be conveniently bypassed for "barefoot" operation.
•
A front panel
"ALC SET"
control
allows convenient adjustment of the ALC threshold. The unique
ALC circuit samples the grid current and power supply voltage.
•
"XMT"
and
"OL"
LED's on the front panel indicate proper operation of the amplifier.
•
A rear panel
12 volt auxiliary output jack
provides up to 200 mA at 12 Vdc for accessories such as the
ART-15 Antenna Tuner.
•
A
step-start circuit
limits the inrush current to the power supply and tube heater. This circuit extends
the life of the amplifier components.
