10
High Voltage Section
The high voltage section of the ALS-600PS uses a full wave bridge rectifier. DC filtering
is accomplished with a large swinging choke (T1) and a high quality computer grade
capacitor (C5). A pair of 100 ohm resistors (R5,6) absorb enough bleeder current to
prevent the output voltage from soaring under low load currents. The output voltage and
current of this section are monitored by a illuminated dual needle meter (M2a/2b).
Primary Circuit
10 ohm resistor (R602) limits the line current during the filter capacitor charge time to
lower the stress on the power supply components. When the 14 volt control line
approaches full voltage relay (RLY601) bypasses the 10 ohm resistor (R602) and applies
full line voltage to the transformer primary. The 10 ohm resistor is protected from supply
shorts by a 2 amp slow-blow fuse (F601) during the start-up.
A separate 10 volt transformer winding can be connected to either oppose or add to the
power line voltage. This allows the 115 volt maximum voltage primary windings to be
adjusted to provide the proper voltage. Use of the buck-boost winding allows maximum
primary voltages of either 100, 110, and 120 volts maximum voltage or 210, 220, and
230 volts maximum voltage at either 50 or 60 hertz.
The primary circuits are fused by two fuses (F1,2) that are rated at 15 amperes at 100
volts, 12 amperes from 110 to 120 volts or 8 amperes from 220 to 240 volts. Since the
current demand and the power factor of this supply are so low Ameritron does not
recommend operating this supply on the higher voltage lines (210 to 240 volts) unless
lower voltages are unavailable.
Low Voltage Circuits
The low voltage power supply sections supply 14 volts positive at 2 amperes maximum
with a full wave grounded center tap supply for
'
control, lights and also to power the bias
voltage regulator and the circuitry of the Bias/Wattmeter board in the ALS-600. This low
voltage circuit is protected by a 2 ampere fuse (F602) located on the power supply
printed circuit board.
A separate half wave rectifier supplies the low current necessary to operate the ALC
circuitry in the ALS-600. This circuit is protected by a 10 ohm 1/4 watt resistor (R601).
SWITCHING POWER SUPPLY CIRCUITRY (ALS-600SPS)
Line Voltage
The input AC line for the ALS-600SPS can be change by moving jumpers on the AC
input terminal block. The ALS-600SPS is factory wired for 120 Vac operation unless
otherwise indicated.
