Note
The Ameritron AL-572 is a linear amplifier designed to provide 1000 watts CW and 1300 watts PEP nominal output power. It operates across all amateur bands from 160 through 15 meters, with support for WARC and 10-meter bands at reduced performance (export models cover 10 meters fully).
Key Features
– Dynamic Bias: An exclusive circuit that reduces idling current during low or no-signal periods, significantly decreasing heat generation and extending tube life.
– True ALC: A front-panel adjustable ALC circuit that samples grid current and power supply loading to maintain signal quality.
– Step-Start Circuit: Limits inrush current during startup to protect the filament and power supply components.
– Multi-Voltage Transformer: A "buck-boost" winding allows the user to select from 14 different primary voltages to optimize performance based on local line conditions.
– Dual Metering:
Left Meter: Provides continuous, simultaneous readings of grid and plate current.
Right Meter (Multimeter): Monitors peak RF power output, Plate Voltage (HV), Reflected Power/SWR, and ALC voltage.
Specifications
INPUT
– Circuit type: Pi-network, slug tuned coils
– Maximum VSWR at resonance: 1.3:1 or less
– Minimum 2:1 VSWR bandwidth: typically 15% of center frequency
– Maximum SSB drive power permissible: 110 watts PEP
– Typical drive for full CW power output: 75 watts
OUTPUT
– Circuit type: Pi-L, Pi-network
– Typical SSB PEP voice operation: 1300 watts nominal
– CW continuous operation: 1000 watts nominal
– 1/2 hour PEP two-tone test: 1000 watts
– 1/2 hour continuous carrier (RTTY): not rated, contact factory for specification
– Frequency Coverage: 1.8 to 21 MHz amateur bands. (Export models include 24.5 and 28 MHz at reduced power. WARC bands available at reduced power)
– Third Order IMD: -34 dB or better (below PEP at rated output)
EFFICIENCY
– CW: approximately 61%
– SSB: approximately 65% (envelope crest)
POWER SUPPLY
– Circuit type: Full wave voltage doubler
– No load voltage: 2900 V
– Full load voltage: 2500 V
– Full load current: 0.7 A
– NL to FL Regulation: 14% or less internal voltage drop
– Transformer: 21 lbs
– Capacitors: 26 mFd total, computer grade
Normal line current at rated CW output: 16 A at 120 Vac
Normal line current at 1300 watt PEP output: 8 A average at 120 Vac
Power line current in standby: 2 A at 120 Vac
TUBES: (4) 572B
– Continuous dissipation: 640 watts
– Warm-up time: 3 seconds
METERING
– Multimeter: Peak forward power (continuously). The second scale switches between peak reflected power (and SWR), ALC threshold, ALC output voltage, and high voltage.
– Current meter: Plate and grid current (simultaneously) on separate scales.
ALC: Negative going, 0 to 10 volts, adjustable.
RELAY: Requires contact closure or sink of +12 Vdc at 100 mA. Back pulse protected.
