AMERITRON ALS-606S User manual

Version 0A 2
Notes:

Version 0A 3
Contents
Introduction ................................................................................................................................................................... 5
Amplifier Features......................................................................................................................................................... 6
Quick Start..................................................................................................................................................................... 7
Installation and Operation .............................................................................................................................................7
Power Line or Mains onnections............................................................................................................................ 7
ALS-600SPS ........................................................................................................................................................ 7
ALS-600PS .......................................................................................................................................................... 8
Radio and Antenna onnections ................................................................................................................................... 9
Operation ................................................................................................................................................................ 10
Alerts.................................................................................................................................................................. 10
General Operation ....................................................................................................................................................... 13
Power Supply and Power Requirements...................................................................................................................... 13
ALS-600PS ........................................................................................................................................................ 13
ALS-600SPS ...................................................................................................................................................... 13
Power Line Requirements....................................................................................................................................... 14
Power Supply Location...................................................................................................................................... 14
Amplifier Overview..................................................................................................................................................... 15
Installation ................................................................................................................................................................... 16
Installation learances............................................................................................................................................ 16
Installation Warnings.............................................................................................................................................. 16
Accessory Equipment and Devices.................................................................................................................... 16
Installation, Wiring, and onnections................................................................................................................ 16
Station Ground ................................................................................................................................................... 17
Safety and Lighting Grounding.......................................................................................................................... 18
oaxial Line Isolators ........................................................................................................................................ 18
Operating Frequency Range ................................................................................................................................... 19
MARS or AP Operation .................................................................................................................................. 19
Warning Lights ....................................................................................................................................................... 20
Interconnection Wiring................................................................................................................................................ 21
Front Panel ontrols...............................................................................................................................................22
Back Panel onnections ......................................................................................................................................... 23
Initial Operation .......................................................................................................................................................... 25
AL Adjustment..................................................................................................................................................... 26
Power Supply Line Voltage Settings........................................................................................................................... 27
ALS-600PS Voltage Settings.................................................................................................................................. 27
ALS-600SPS Voltage Settings ............................................................................................................................... 28
ALS-606 Functional Overview ................................................................................................................................... 28
General Operation................................................................................................................................................... 28
ATTENUATOR BOARD.................................................................................................................................. 29
PA Amplifier...................................................................................................................................................... 29
1KWF6 Low Pass Filter Assembly.................................................................................................................... 30
ontrol and Protection Logic.............................................................................................................................30
SWR Directional oupler .................................................................................................................................. 30
ircuit Boards......................................................................................................................................................... 30
1KWF6 ..............................................................................................................................................................30
BSW3................................................................................................................................................................. 30
B2.................................................................................................................................................................... 31
MB2 ................................................................................................................................................................... 31
PAM-606 ........................................................................................................................................................... 31
PD8m ................................................................................................................................................................. 31
RJ45 ................................................................................................................................................................... 31
RLY ................................................................................................................................................................... 31
SWR................................................................................................................................................................... 31
Schematics................................................................................................................................................................... 32

Version 0A 4
Filter 1KWF6..................................................................................................................................................... 32
Bandswitch BSW3............................................................................................................................................. 33
SWR Directional oupler Board ....................................................................................................................... 33
ontrol Board B2 ............................................................................................................................................ 34
Metering Board MB2......................................................................................................................................... 35
PA Module PAM-606 ........................................................................................................................................ 36
Power Attenuator PD8m .................................................................................................................................... 36
Interface onnections RJ45 ............................................................................................................................... 37
Relay Board ....................................................................................................................................................... 37
ALS-600PS Power Supply................................................................................................................................. 38
ALS-600SPS Switching Power Supply ............................................................................................................. 40
ALS-606 Limited Warranty......................................................................................................................................... 44
Tables
Table 1 Quick Start Fault Alarms................................................................................................................................ 11
Table 2 Band Frequency Ranges ................................................................................................................................. 19
Table 3 LED Alarm Indicators .................................................................................................................................... 20
Table 4 ALS-600PS Voltage Settings ......................................................................................................................... 27
Table 5 ALS-600SPS Jumper Settings ........................................................................................................................ 28
Figures
Figure 1 Quick Starts Typical Wiring .........................................................................................................................12
Figure 2 Amplifier Interconnection............................................................................................................................. 21
Figure 4 Front Panel .................................................................................................................................................... 22
Figure 3 ALS-606 Back Panel..................................................................................................................................... 23
Figure 5 ALS-600PS Board......................................................................................................................................... 27
Figure 6 ALS-600SPS Board Diagram ....................................................................................................................... 28
Figure 7 1KWFL6 Filter Board ................................................................................................................................... 32
Figure 8 Bandswitch BSW3 ........................................................................................................................................ 33
Figure 9 SWR Power Sensor Board ............................................................................................................................ 33
Figure 10 ontrol Board B2 Part 1........................................................................................................................... 34
Figure 11 ontrol Board B2 Part 2........................................................................................................................... 34
Figure 12 Meter Board MB2 ....................................................................................................................................... 35
Figure 13 PA Module PAM-606 ................................................................................................................................. 36
Figure 14 Attenuator PD8m ........................................................................................................................................ 36
Figure 15 TR Relay Board .......................................................................................................................................... 37
Figure 16 ALS-600PS Power Supply .......................................................................................................................... 38
Figure 17 ALS-600PS Board....................................................................................................................................... 39
Figure 18 ALS-600SPS Main Wiring.......................................................................................................................... 40
Figure 19 ALS-600SPS A /D Section ..................................................................................................................... 41
Figure 20 ALS-600SPS Board Driver Section ............................................................................................................ 41
Figure 21 ALS-600SPS Board A /D Section 2 .......................................................................................................42
Figure 22 ALS-600SPS Board D /D Section .......................................................................................................... 42
Manual Version 0A 04/12/17

Version 0A 5
Introduction
Thank you for purchasing this amplifier system.
The ALS-606 is a compact 600-watt nominal PEP output amplifier. It uses an e ternal
power supply system. This amplifier covers 160-6 meters. Nominal drive power is 75-
watts or less. NOTE: This amplifier excludes all operation between 25 and 28 MHz
The ALS-606 interfaces with most modern amateur radio transceivers. Supported band
data input includes ICOM compatible analog voltage, Elecraft and Yaesu BCD band
data, and Kenwood serial data. With proper interface cables and data, this amplifier will
automatically change bands in step with transceiver band changes. Automatic band
selection using a band data port or band decoded bus requires purchasing an Ameritron
interface cable for your radio.
Carefully unpack this amplifier and power supply. Please inspect everything for physical
shipping damage; this includes cabinets and chassis. Ameritron does not package
dented or damaged units. Cabinets and controls can be broken, bent, or dented with
rough handling. If a new unit arrives mechanically damaged, including broken knobs or
switches, it is always from handling somewhere between Ameritron and the end user. In
the event of cabinet damage or broken controls, please contact the dealer immediately.
To permit claim processing, retain all bo es and packing materials.
The Ameritron ALS-606 is 600-watt nominal output, 160 through 6 meter amateur radio
band, solid-state amplifier. The ALS-606 uses four 50-volt linear RF MOSFETS. These
MOSFET’s are specifically designed for linear power amplifier applications, rather than
non-linear or pulse service. They provide lower SSB distortion when compared to non-
linear application solid-state devices in SSB service. Fan speed is regulated by
temperature sensors; assuring conservative cooling with minimal noise.
Nominal driving power is 75-watts for 600-watts output (appro imately 9 dB gain) on
most bands. The compact 9-1/2” wide by 7” high amplifier package (depth only 14”) fits
nearly any station configuration. This attractive desktop amplifier unit weighs
appro imately 15 pounds.
An e ternal 50-volt 25-ampere CCS power supply powers the ALS-606. Two different
supplies are available. The ALS-600SPS switching regulated supply and the ALS-
600PS unregulated supply. These supplies operate on all standard residential power
line voltages.
Caution: This amplifier has an FCC mandated automatic disconnect and other features
preventing 27-MHz operation There is no available circuitry or control provision to
circumvent this lockout
Please read the manual completely and understand the operations before trying
to operate this amplifier

Version 0A 6
Amplifier Features
This amplifier provides the following standard features:
ɀ 160 through 6-meter operation, full-power on si meters.
ɀ Four conservative linear-service rated 50-volt MOSFET transistors.
ɀ New push-pull stripline PA layout with e ceptional VHF performance.
ɀ Energy-efficient solid-state design greatly reduces heat, <100-watts power line
draw on receive.
ɀ E ceptional harmonic suppression.
ɀ Operational in a few seconds, no long filament warm-up time.
ɀ Clean layout with easy-to-service modular construction.
ɀ Quiet variable-speed forced-air cooling system.
ɀ Power module current and voltage meters with LED illumination.
ɀ Accurate PEP Forward and PEP Reflected output power metering.
ɀ Reflected power protection.
ɀ Thermal overload protection.
ɀ Bandswitch error protection.
ɀ Easy to understand front panel LED indicators for rapid fault-error diagnosis.
ɀ Standard negative-going ALC output with front panel adjustment.
ɀ ALC metering and ALC LED indicator.
ɀ Fully-regulated e ternal switch mode power supply, or linear unregulated supply.
ɀ Compact size 14” deep 7” high 9.5” wide.
ɀ Weight amplifier section 15 pounds.

Version 0A 7
Quick Start
Installation and Operation
WARNING: Do not block ventilation holes. Do not expose to moisture,
water, or external heat.
This power amplifier system consists of two units, a power supply and an amplifier
section. The amplifier section has metering and operator functional controls. Locate the
amplifier section at a convenient place with proper space for airflow, within the
operator’s reach and view. The power supply can be placed anywhere within cable
length limits. Do not e tend the amplifier power supply dc power cable.
Power Line or Mains Connections
There are two distinctly different power supplies available for the ALS-606. The ALS-
600PS is more basic unregulated choke input supply. The ALS-600SPS is a state-of-
the-art regulated switching mode supply. Please read the appropriate sections below.
For non-e port use, each supply comes with a standard NEMA 5-15P two-blade 120V
15A plug with round safety-ground pin.
Overall amplifier operation remains similar with either supply; e cept the linear supply
has a RTTY and Normal voltage switch. The RTTY position allows higher amplifier
efficiency at reduced power. See the power supply details included with the particular
power supply for details specific to each supply. This includes operation on various line
voltages, power supply operation, fuse selection, location, and power supply trouble
shooting.
Non-e port versions of Ameritron ALS-600 series power supplies are wired and fused
for 120Vac USA power mains, but all are modifiable to other standard power mains
voltages.
AL -600 P
The USA standard version ALS-600SPS is supplied wired for 95-135 Vac, 50-400 Hz,
15-ampere or larger electrical service. Reconfiguring internal jumpers on the power
supply board will allow 185-260 volt operation.
The ALS-600SPS is internally regulated. Beyond 120 or 240V concerns, the ALS-
600SPS does not require voltage tap changes. There should be very little change in
HV1 (PA voltage) with amplifier power and line voltage. Less than 3 volts change from
the 50Vdc nominal voltage is acceptable.
Do not operate with line voltage below 95 or above 135 volts when wired for 120 volts,
or below 185 or above 260 volts when wired for “240 volts”.
Unless power mains fall below 100 volts, the ALS600SPS switching supply provides the
same performance on 120-volts as on 240-volts. The only function reasons for 240-volt
power mains are light dimming and unintentional circuit breaker opening. If outlet wiring
is already loaded heavily, or if house wiring is sized too small for the distance to the

Version 0A 8
mains supply, you may have to use a dedicated 120-V amplifier line, or rewire the
supply and use 240-volt mains.
With 120Vac mains at 600-watt nominal RF output, current draw is appro imately 12
amperes on steady carrier. Peak line current is typically much less than 8 amperes at
600 watts PEP on SSB voice.
The ALS-600SPS can be located anywhere, within reach of interfacing cables,
convenient to your operating setup. The location must be dry, airflow must not be
restricted, and outside temperature must not be over 120F (49C). You must not e tend
or shorten the amplifier to power supply cable.
E ceeding safe power supply load current forces the switch mode supply into shutdown.
Restore operation by turning the main power switch off for a brief time. If the power
supply detects a permanent overload or the supply has failed, the supply will not reset.
AL -600P
The ALS-600PS uses a standard transformer with choke input filter system. It weighs
significantly more than the ALS-600SPS, and is not voltage regulated.
The ALS-600PS requires a 100-130 Vac, 50-60 Hz, 15-ampere or larger mains supply.
This supply is reconfigurable for 210-250 volts by moving internal jumpers. The line cord
uses a standard USA NEMA 5-15P two-wire male plug with safety ground.
This supply is unregulated. Voltage range includes all typical residential power line
voltages, but the internal buck-boost winding must be reconfigured if output voltage is
more than 58 volts no load. Operation with no load voltages over 58 volts can
compromise FET reliability.
With 120Vac mains, current draw with steady 600-watt carrier is typically around 12
amperes. Line current is typically less than 8 amperes at 600 watts PEP SSB voice.
The ALS-600PS normally provides the same performance at 120-volts as at 240-volts,
unless the power mains have e cessive voltage drop. If you e perience light dimming or
line breaker opening, move the supply to a dedicated 120-V line, or reconfigure the
supply for, and use, 240-volts.
This supply does not have overload protection, other than standard fuses.
See the “Power Supply Line Voltage Settings” starting at page13 for changing the line
voltage settings.

Version 0A 9
Radio and Antenna Connections
WARNING: Forcing connector engagement can result in permanent connector
damage. Solder on the outside of center pins or bent pins are primary causes of
female connector damage. E ternal solder or bent center pins can permanently
damage the female.
Do not use Line Isolators on amplifier RF cables. The chassis of the amplifier should
be at the same RF potential as all other desk equipment. Shield isolators allow
equipment to float to different RF chassis potentials. Different chassis potentials are
e actly what we do not want, and isolators on desk coa ial cables encourage differing
enclosure RF voltages. It is better to cure RF problems outside the operating position.
RF connections are through standard UHF female connectors. Use 50-ohm coa ial
cables with quality, properly soldered, UHF male (PL259) connectors. The output cable
must safely handle at least 600 watts.
E amine the RF connectors. Female SO-239 UHF connectors have notches on the
outer threaded-area edge. PL259 UHF males have protruding tabs on the metal outside
the center-pin insulator. These tabs and notches prevent unwanted connector rotation.
The male tab or tabs must align and fit into female notches. This interlocking prevents
connector rotation. It is best achieved by slightly wiggling or rotating the cable while
hand-tightening the male’s shell to seat the male tab into the female notch.
With a firm handgrip, while making sure the PL259 male connector tab interlocks with
the amplifier’s SO-239 chassis connector notch, gradually tighten RF connectors. Do
not use e cessive force on connectors. Check for proper tightness and seating by
wiggling and fle ing the cable and watching for any male connector movement on the
female. Properly seated, connectors will be solidly locked without use of pliers or tools.
ALC and Relay (keying or TX line) connectors are standard phono females. Phono
males from e ternal cables should push directly in with a snug, but not overly tight.
The Relay line operates with low voltage (<12V) and low current (<20 mA). Transmit is
enabled by pulling the Relay line to ground with a relay contact or transistor. Read your
radio manual. Unless you have a very unusual radio, your radio should directly key this
amplifier. Avoid using e ternal interfaces with relays. Amplifier relay switching time is
appro imately 10-12 mS.
The remote and radio band data connectors are specialized connections. They are for
use with Ameritron supplied cables only.

Version 0A 10
Operation
Before attempting operation:
This amplifier is optimized for 50-ohm loads. Be sure your antenna system 50-ohm
SWR is as low as possible. As SWR increases from 1:1, either heat or distortion will
increase.
Be sure your antenna system, including any switches, baluns, matching circuits, or
lighting protection devices, are in good condition and will safely handle high power.
Connectors, cables, and antennas must not have loose connections or insulation
failure issues.
Your e citer must be adjustable to significantly less than 100-watts output. Start at 50
watts ma imum drive power and increase or decrease drive to reach desired power.
Do not e ceed 25 amperes or 600 watts, and do not drive into non-linearity on SSB. A
trapezoid scope pattern is recommended for drive adjustment. Overdriving results in an
e cessively wide signal, and overdriving can damage the amplifier.
Power mains should be reasonably stable and match power supply voltage wiring.
The low pass filters cut off just above the traditional primary amateur bands. A primary
band’s filter is used on the ne t lower WARC band. For e ample, the 20-meter low
pass filter is used on 30 meters. Some radios do not supply enough band data to know
the e act band. With these radios, amplifier band data displays the next higher
primary band above the radio’s WARC band. If you are using such a radio, do not be
alarmed if 15 meters illuminates when the radio is on 17 meters. This is still the correct
filter.
The amplifier will automatically attempt to reduce power if it appears thermal limits will
be reached.
The amplifier will shut off with an incorrect band selection, high antenna SWR (even for
an instant), if safe thermal limits are reached, or with catastrophic failures.
The ALS-606 reads peak envelope power on forward and reflected RF power scales.
Alerts
This amplifier has front panel alert codes using the SWR, PA, TX, warning LED’s and
bandswitch band indicators. When a fault code appears, the amplifier is disabled. When
an operating problem is corrected, operation is restored and alerts canceled by moving
the front panel Standby/Operate switch to Standby.

Version 0A 11
The following table applies to faults:
Warning
light Steady
Warning
light Flash
Fault Cause or Cure
SWR TX Antenna Reflected
Power
High antenna SWR or
intermittent antenna or feed line
connection
SWR, PA Band Wrong filter
Filter input SWR
E citer or amplifier on
incompatible band, filter failure
PA, TX PA FET too hot E cessive power for duty cycle
or SWR, lack of proper airflow
10M, PA,
TX
Illegal 11 meter E cessive 27 MHz signal level
REM, PA No data or bad band
data when on remote
Defective or improper remote
cable, or bad radio band data
information
Table 1 Quick Start Fault Alarms
With proper station installation, and with low antenna SWR, amplifier operation is
straightforward:
Set the bandswitch to the desired band. This happens automatically in the REM position
with a suitable radio interface cable. Set ALC full clockwise. Turn the amplifier power
switch ON, but leave the amplifier in STANDBY.
Set the e citer or transceiver to 50 watts carrier power. This power should show on the
amplifier’s FORWARD POWER meter. REFLECTED power should be very low.
Move the amplifier standby-operate switch to OPERATE.
Transmit while watching the Forward Power reading, quickly adjust e citer power for
less than 25 amps Id current, or less than 600-watts power output.
For high duty cycle modes and long transmissions, or if linearity is a problem, reduce
power. The amplifier has overload protection circuits, and will also attempt to reduce
power if the FET’s approach un-safe limits, but it is best to not rely on protection.
Adjust ALC to limit either forward power or amplifier PA current to a desired value at or
below ma imum ratings, counterclockwise reduces power and current. The ALC light
should just flicker if ALC is limiting power properly. If the ALC light is on almost
continuously, reduce the transmitter’s power output setting.

Version 0A 12
Figure 1 Quick Starts Typical Wiring

Version 0A 13
General Operation
Power Supply and Power Requirements
AL -600P
Power Supply Features
Normal operating range is from 100 volts up to 130 volts 50/60Hz (12-amperes
typical full carrier power) or between 200 and 250 volts, 50/60Hz (6 amperes
typical at full carrier power).
A unique "buck-boost" winding allows compensation for up to si different power
line voltages centered on 115 and 230 volts. This versatile Ameritron feature
maintains optimum voltages on the amplifier components for ma imum
performance and life
The ALS-600PS standard power supply uses an input choke to provide low
power factor loading on power lines. This reduces the peak currents drawn from
the line and improves the voltage regulation of the supply. This makes the ALS-
600PS generator and inverter friendly within the acceptable power line frequency
range of 50 to 60 Hz
Step-start to limit stress on power supply components
An illuminated cross-needle meter monitors 50V line output voltage and current
Weight 33 lbs.
AL -600 P
Power Supply Features
Efficient operation from 100-130 volts ac (12 amperes typical at full output power)
Low standby and receive power drain, typically less than 100-watts
Generator and inverter friendly with acceptable power line frequency range 40 to
400 Hz
Fully-regulated current-limited outputs
E cellent voltage regulation
E ceptional filtering and RFI suppression eliminates receiver birdies common to
most SMPS
Light weight 13 lbs.
Inrush protection
An illuminated cross-needle meter monitors 50V line output voltage and current.
The ALS-606 e ternal power supplies contain 14-volt positive and negative supplies, as
well as a 50-volt 25-ampere continuous (30-ampere peak) main supplies. The ALS-606
PA (power amplifier) module operates from 50-volts, giving a total dc supply rating of

Version 0A 14
1250 watts average power and 1500 watts peak dc power. The 12-volt supplies are for
illumination, bias, and control functions.
Power supply to amplifier interconnections are through a heavy-duty cable using reliable
Cinch Jones connectors.
Power Line Requirements
This amplifier ships wired for a nominal mains voltage of 120 Vac with either supply.
Ma imum power line current at full power output is 12 amperes at 120 volts. 250-volt
rated 15-ampere fuses protect the power line. Always use 125V or 250V line fuses.
The linear supply requires changing taps for different line voltages. The switching power
supply is voltage regulated, current limited, and automatically adapts to any mains
voltage between ~95 Vac and 135 Vac. The ALS-600SPS switching supply does not
require adjustments or voltage tap changes.
See the “Power Supply Line Voltage Settings” starting at page13 for changing the line
voltage settings.
Note: 240-volt power mains operation is possible. This will not normally increase power.
Because average power is very low, SSB operation is generally unaffected by 120- or
240-volt operation. 240-V fuse size is 8-amperes ma imum, fast blow only. The fuse
must have a voltage rating of 250VAC
Power upply Location
Locate the power supply in a ventilated area convenient to the amplifier location. Avoid
placing the power supply ne t to sensitive equipment, such as audio processors,
transceivers, or microphones. For safety, ground the wing nut stud on the supply rear to
the station ground buss. The station ground buss should comply with National Electrical
Codes. NEC safety and fire protection codes mandate direct bonding of station grounds
to the home power line entrance ground. Station ground rods not directly bonded with a
low impedance connection to utility entrance grounds will increase equipment or
property damage, and increase personal risk, significantly.

Version 0A 15
Amplifier Overview
The Ameritron ALS-606 is a solid-state, 600-watt nominal RF output power, 1.8-54 MHz
amplifier. The ALS-606 meets or e ceeds all FCC requirements governing amateur
radio e ternal power amplifiers.
The ALS-606 uses four low-distortion MRF-150 (or equivalent) SSB RF power
transistors in push-pull parallel. Ameritron recommends running 600 watts or less peak
power for ma imum linearity and component life. It is always a good idea to use an
oscilloscope to verify proper linear SSB operation.
Protection circuitry reduces power as transistors approach conservative thermal limits,
and disable the amplifier before e ceeding safe transistor operating temperature limits.
(See warning table.) A fan speed-control system monitors heatsink temperature.
Room temperature amplifier bias is nominally 250 mA per FET, or appro imately 1-
ampere total. Amplifier supply voltage is nominally 50-Vdc. Ma imum allowable voltage
is 58 volts.
Harmonic suppression comes from push-pull operation of linear devices, followed by 5-
pole low-pass filters. This amplifier uses modern multi-layer high voltage chip capacitors
where applicable. Chip capacitors, due to low internal inductance and higher Q, offer
significantly improved harmonic suppression. Harmonic and spurious suppression is
e cellent; e ternal low-pass filters have minimal effect on TVI. The most likely cause of
any RFI or TVI will be fundamental overload from inadequate consumer device RFI
immunity.
Relay switching time is appro imately ten milliseconds. Radio adjustable TX delay
should be set to 10 mS.
The T/R “Relay” control jack is well within the range of almost any transceiver or radio.
The “Relay” jack has an open circuit voltage of appro imately 12 volts, and closed
circuit current less than 15 mA. Virtually any modern amateur radio will directly key this
amplifier.
This amplifier includes full metering using large easy-to-read conventional cross-needle
panel meters. The meters read all critical parameters, including Forward and Reflected
peak envelope RF power.

Version 0A 16
Installation
Please look your amplifier and power supply over carefully. Observe the air inlet and
outlet ventilation holes. Facing the amplifier front panel, the cooling air inlets are on the
top left and lower right side, including the right hand side cabinet bottom. Warm air e its
vents at the cabinet rear.
While outlet air will not be particularly hot, it is never a good idea to have warm air blow
into heat sensitive equipment, such as transceivers or other power amplifiers. Have the
same consideration for your new amplifier and power supply. Be sure air inlet
temperature is not substantially above normal room temperature. Ideally, the air inlet
temperatures should be below 32° C or 90° F, although temperatures up to 41° C or
106° F are permissible. Should ambient temperatures e ceed these limits, it might
become necessary to reduce duty cycle or power.
Warning: Do not block cooling air inlets and outlets!
Ne er expose the amplifier to excessi e heat, dirt, water, or mist.
Installation Clearances
The amplifier must have a clear area to the bottom, both sides, and top for proper
airflow and to the rear for e haust air and interconnection wiring. It is especially
important to avoid obstructions that block the air inlet on the top left, as well as both
lower sides. One to two inches clearance is normally adequate for full ventilation. Keep
any papers or loose objects that might impede airflow away from the air inlets and
outlets.
Locate the amplifier and power supply away from sensitive equipment such as
microphones, audio processing equipment, or low level audio or radio frequency
amplifiers. Generally, the best location for the power supply is below the operating desk
and away from antenna feedlines. This will minimize unwanted mechanical, acoustical,
and electrical coupling.
The power supply produces very little heat, but the air inlet and outlet must remain open
to normal room temperature air.
Installation Warnings
Accessory Equipment and Devices
Second to operator error, the most common amplifier failure or erratic fault protection
shutdown is from antenna switches, lightning protection devices, or baluns with lightning
spark gaps in high SWR coa ial lines. Do not use 50-ohm lightning protection devices
on lines with high SWR, such as between and antenna and antenna tuner. Be sure any
lighting protection devices are in working order.
Installation, Wiring, and Connections
The ALS-600SPS switching power supply is factory wired for 100-130 Vac. The linear
ALS-600PS is prewired for 120-125 Vac nominal voltage. Both use standard NEMA-5-

Version 0A 17
15P 15-ampere 120-volt plugs. The round center pin is the safety ground. Do not
remove the safety ground.
CAUTION! Before connecting the power supply to an electrical outlet, always be sure
you have completed the following four steps:
1 Insert the 15-ampere 250V fuses into the two black fuse caps
2 Insert the fuse and cap assemblies into the power supply’s fuse holders
The fuses lock in place with a push and slight turn
3 Connect the power supply to the amplifier
4 Be sure the amplifier power switch is off
Caution! Fuses ha e both oltage and current ratings. Use only 250V rated
fuses in this de ice. The oltage rating is generally marked on fuses. DO NOT use
automoti e-type low oltage fuses in any power line application. See power
supply instructions.
Warning: Ne er insert the power supply cord into the outlet until you ha e
completed steps 1 through 4 abo e!
Position the amplifier at or near the desired location on your operating desk so you have
access to the rear panel, and connect the rear panel cables. Do not connect the
power mains at this time!
tation Ground
Common rumor is a station equipment ground reduces RFI (radio frequency
interference), reduces lightning damage, or improves signal levels. Generally, changes
in RFI or signal quality, with the addition or removal of a station ground, indicate an
antenna or feed line installation problem. Typical problems causing desktop RF
problems include the following:
ɀ Lack of suitable baluns.
ɀ Improper feed line routing near antennas, or improperly designed antennas.
ɀ Antennas too close to the operating position.
ɀ Poor equipment cabinet design, such as non-bonded or grounded equipment
covers or panels.
ɀ Poorly designed low-level audio line shield entrances, such as shields allowed to
enter cabinets instead of grounding at the enclosure entrance.
ɀ Improper antenna feed line building entrance, lacking a properly grounded
entrance panel.
ɀ Rather than patching a system problem at the desk, it is much better to correct
the actual problem source.

Version 0A 18
afety and Lighting Grounding
The power supply cabinet grounds through a safety ground pin on the power plug. This
system depends on a properly wired power outlet.
Lightning protection grounds do very little good at the operating desk. Lightning
protection grounds belong at the antenna cable entrance to the building. Station ground
rods must always electrically connect through low impedance and resistance
conductors to the power line entrance ground. The national electrical code in the USA
prohibits isolated ground systems at dwelling entrances. Isolated ground rods or
systems connected to conductors entering a dwelling increase damage likelihood during
storms, and increase fire hazard and shock risk.
RF grounds generally belong at the antenna or at the feed line entrance. With the
special e ception of a small floating counterpoise grounds, RF grounds at or very near
the dwelling should bond into the mains ground outside the dwelling. This is especially
true with earth contact grounds.
There is a ground lug on the amplifier rear panel. This ground lug provides a convenient
chassis connection for operating positions with ground bus on the desk. A station
ground bus helps ensure desk area equipment cabinets are close to the same electrical
potential for radio frequencies and lower. Equipment ground lugs are NOT for
independent wires or connections to e ternal ground rods or ground systems from each
piece of equipment. They are for connection to a desktop ground bus system common
to all equipment, if you prefer to use such a system.
Independent ground wire connections are counterproductive. Never use RF isolators
between the amplifier and radio. Never use long independent wires to e ternal grounds.
Never connect desk equipment to ground rods that do not bond into the mains entrance
ground rod.
Coaxial Line Isolators
The goal of every operating position is to maintain all equipment cabinets and housings
at the same RF potential. Never install coa ial line isolators between desktop radio
equipment. Isolators on or near the desk are contrary to this goal, and actually promote
or encourage RF potential differences between different desk equipment. If an RF
problem appears at the operating position, correction, repair, or replacement of
defective equipment is in order.
Proper line-isolator installation points are either just outside the operating room entrance
and/or close to the problem’s actual source. If the antenna system has e cessive
common mode current on feedlines, the desktop has defective cables or connectors, or
if equipment has poor equipment cabinet design such as poor cover bonding to chassis,
locate and correct the actual problem.

Version 0A 19
Operating Frequency Range
This amplifier covers all Amateur Radio frequencies below 54 MHz, as restricted by
FCC or your local governing authority. Once you have established proper connections,
please set the amplifier BAND SELECT control (Fig. 2, ref 3) to one of the following
bands:
Band Frequency
Range
Notes
160 1.8 - 2 1 MHz
80 3.2 - 4 2 MHz
40 6.0 - 7 5 MHz
30 7.5 - 14 5 MHz USA 30-meter power limit currently 200-watts
20 7.5 – 14 5 MHz
17 14.5 – 22 0
MHz
15 14.5 – 22 0
MHz
12 22.0 – 30 0
MHz
Amplifier automatically disables above 25 MHz
10 22.0 – 30 0
MHz
Amplifier automatically disables below 28 MHz
6 50.0 – 54 0
MHz
Table 2 Band Frequency Ranges
Caution: This amplifier has an FCC mandated automatic disconnect and other features
preventing 27-MHz operation There is no available circuitry or control provision to
circumvent this lockout
MAR or CAP Operation
For licensed amateur radio operators participating in Military Affiliate Radio Systems or
CAP, this amplifier is suitable for use on all frequencies between 1.8 and 54 MHz with
some precautions. The upper frequency limits are in bold type in the table above. Do not
operate above the bold-type frequency limits in the table above or PA (power amplifier)
or filter damage may occur.
This amplifier has significantly cleaner output purity than FCC part 97.307 requirements
(January 2016) when operated inside all amateur bands listed in the table above.
Ameritron does not guarantee harmonic suppression or operation in applications outside
standard amateur radio bands.

Version 0A 20
Most non-amateur services prohibit use of non-commercial radio equipment. This
amplifier automatically prevents operation between 25 and 28 MHz. Operation in the 25-
28 MHz range is not available with this product, irrespective of licensing or end-use.
Warning Lights
The ALS-606 has two primary warning lights in the center of the front panel, SWR and
PA. When SWR or PA warnings illuminate from an operating fault the amplifier defaults
to a forced bypass mode. Operational faults and the forced bypass reset by placing the
amplifier in standby.
ALC: The yellow ALC light is at the far left of the warning light cluster, ne t to the ALC
control. The yellow ALC light is not a fault indicator. The ALC light indicates ALC output.
Occasional flashing is normal with properly adjusted ALC. An almost steady ALC light
generally indicates too much ALC.
TX: The TX indicator illuminates steady green when the amplifier is “keyed” or in the
transmit mode.
The SWR and PA indicators serve e clusively as warnings. The SWR and PA, in
conjunction with TX and Band indicators, flash in certain “codes” to indicate severe
operational problems.
The following table applies to faults:
Warning
light Steady
Warning
light Flash
Fault Cause or Cure
SWR TX Antenna Reflected
Power
High antenna SWR or
intermittent antenna or feed line
connection
SWR, PA Band Wrong filter
Filter input SWR
E citer or amplifier on
incompatible band, filter failure
PA, TX PA FET too hot E cessive power for duty cycle
or SWR, lack of proper airflow
10M, PA,
TX
Illegal 11 meter E cessive 27 MHz signal level
REM, PA No data or bad band
data when on remote
Defective or improper remote
cable, or bad radio band data
information
Table 3 L D Alarm Indicators