review is from O Gauge Railroading, January 2000. Reprinted with permission of
Myron J. Biggar Group, Inc..
Atlas O AEM7/ALP44 Electric
Review by Barry Lewis
Atlas O seems to believe "less is more." The
company doesnt treat us to a barrage of new products each year, but it does try to
make each release stunning: A prototype thats never been modeled in O gauge, superb
detailing and pushing the envelope in a few ways. The AEM7, Atlas Os first road
locomotive, satisfies those criteria.
The AEM7 is the prototypical "little engine that could,." Created as
Amtraks successor to the GG1, it had mighty big shoes to fill. The Gs were
legendary. Born in the Depression and still running after four decades, they had
epitomized the "Pennsylvania Railroad of the World" (modesty being on eof the
few virtues the Pennsy did not claim). Inside an 80" exterior styled party by famed
industrial designer Raymond Loewy, the Gs had the guts to deliver 4,620 continuous
horsepower, or more than 8,000 horsepower short term.
By the late 1970s, however the gg1s were showing their age and Amtrak was looking for a
replacement. It already had one failure with the General Electric E60CP, which had a
propensity for derailing. Bear in mind that, unlike a diesel, a mainline passenger
locomotive that runs from overhead wires was not something that could be bought off the
lot, then or now. Low demand dictates that such an engine could be custom-designed and
So Amtrak looked to Europe, where mainline electrification is more common. In the
Swedish Rc4 made by Allmanna Svenska Elektriska Aktiebolaget (ASEA), it found the basis of
a solution. Amtraks AEM7 is outwardly similar to the Swedish engine and is
manufactured collaboratively by ASEA and the Electro-Motive Division of General Motors
(EMD). Packed into a 50 framejust over half the size of a GG1is an
engine that easily rivals the G in horsepower (7,000) and sustained top speed (125 mph).
until Amtraks Acela enters service between Washington and Boston, the AEM7s are the
fastest engines on American rails.
About the only thing the AEM7 lacks is the styling genius of Raymond Loewy; rail fans
have dubbed the engines "toasters" for their boxy appearance. The real name, by
the way, stand for ASEA ("A"), EMD ("EM") and 7,000 horsepower
Amtraks original orders for AEM7s were delivered between 1979 and 1982.
Witnessing the success of the engines in high-speed Northeast Corridor service between
Washington and New York, several commuter operations decided to order the engine as well.
MARC purchased engines in 1986 for service between Baltimore and Washington, and SEPTA
took delivery of AEM7s in 1987 for Philadelphia area service. Amtrak bought additional
engines in 1988.
A similar engine, the ALP44, is owned by the New Jersey Department of Transportation
(NJ TRANSIT). Arriving in three orders between 1990 and 1997, these engines were
manufactured wholly in Sweden by ASEA Brown Boveri (ABB). the major external difference
between an ALP44 and an AEM7 is the larger vents along the top of an ALP44s sides.
According to Jim Weaver at Atlas O, Amtrak AEM7s have occasionally doubleheaded with
MARC and SEPTA units, and he has the photos to prove it. NJ Transit has also borrowed
SEPTA units on occasionso theres certainly a prototype for modelers wishing to
mix paint schemes.
Atlas Os version of the AEM7 is a superb model, built to prototype dimensions and
featuring virtually all the external features of the real engine. As with all of Atlas
Os models, both the body casting and the added-on details have the delicate look of
a true scale model, while being durable enough to take repeated handling.
On the plastic body casting, the grille work along the tops of the sides is especially
well done. All of the prototypes grab irons are reproduced as separate metal pieces,
although strictly speaking the grab irons should be the same color as the body paint
beneath them (white, blue and black on the Amtrak model, for example), rather than all
being chrome. The windshield wipers are also metal for durability.
Although you have to look closely to see it, both cabs have full interior detail:
seats, control handles, an electrical cabinet at the back and gauges back-lit by the same
bulb that illuminates the headlight. The front cab has a nicely painted figure in each
seat. (The front cab on these double-ended locomotives designated by a tiny "F"
on the lower side of the car body, under the cab window.)
As with many electric locomotives, the really interesting details are on the roof.
Atlas has done fine job of duplicating the maze of electrical conduits, insulators, radio
antennas and other gear on the top of the prototype. The white boxes on the roof of each
cab are air conditioners, similar to those found on the roof of motor homes. Turns out it
was somewhat impractical for Amtrak engineers to open the windows for cooling at 125 mph!
At least some MARC and SEPTA engines do not have this feature, although its on all
of the Atlas O models.
The pantographs are lacy, accurate models of the versions used on the AEM7 as
originally delivered (some engines received modified plans in later years). Although they
may seem to reach rather high in the "up" position, the up-height of Atlas O
pantographs compares perfectly with prototype photographs. Pantographs on the MARC, SEPTA
and NJ TRANSIT molds are prototypically painted red. Some Amtrak engines were later
equipped with red pans also; Atlas O has these available as spare parts for owners wishing
to modify Amtrak engines.
A solder lug at the base of each pantograph, inside the engine body, allows them to be
used for actual current pickup. To do that, one must disconnect the wires to the third
rail rollers and very carefully solder the same wires to the pantograph lugs to avoid
melting the plastic body, Atlas O will be providing instructions for this conversion in
the future, and phone support from Atlas O technicians is also available.
my friend Marty Fitzhenrys layout features working catenary made from Marklin
components, and we found the Atlas O pantographs tracked perfectly on the overhead
(although we didnt rewire them to actually pick up current.) Marty says these are
the first pantographs hes found that had sufficient tension for reliable current
pickup right out of the box. With pantographs from MTH, Williams and others, he has needed
to add extra springs to provide sufficient upward tension.
The underside of Atlas Os model also features much better-than-average detail.
The unique trucks are accurately reproduced with see-through areas around the journals.
Theres a separate brass-colored bell and nice detailing in the area between the
trucks. And the pilots on each end include separate steps, air and signal lines, and
coupler lift bars.
Paint work on the Amtrak and other MARC samples we examined was extraordinary. I would
think painting Amtraks lettering and stripes on the AEM7 would be a painters
nightmare, but Atlas O carries it off perfectly. The borders between Amtraks red,
white and blue stripes were absolutely crisp on our sample, without even the faintest hint
of overspray between the colors. The white edging around the engine numbers on the
corrugated sides and around Amtraks name on the ends was flawless. And the large
Amtrak lettering on the sides was applied beautifully. The striped paint scheme on our
MARC sample was just as neatly applied, and featured minute, legible (with a magnifier!)
EMD logos on the lower sides. A difficult part of the MARC scheme is the orange panel
around the headlights, which was crisply done on the Atlas O model with no overspray.
Removing the body shell from one of our sample engines, we found a neatly laid-out
interior. All electronics are on a single printed circuit board fastened to the roof;
theres none of the spaghetti of wires found in some engines loaded with electronics.
The die-cast chassis holds a large Pittman motor with two big flywheels mounted
horizontally and driving a gear tower on each truck. Above each truck is a large metal
weight. As with the Atlas O earlier switcher, the AEM7 is put together with easily
accessible screws to make light repairs simple.
Performance: Conventional Mode
Pushing the envelope electronically, this engine introduces LocoMatic, a control system
developed by Atlas O and Dallee Electronics that offers push-button operation of several
engine features, plus a form of command control compatible with Lionel TrainMaster
command. However, the engine is fully compatible with all current transformers and runs
fine without the LocoMatic control box. To evaluate the AEM7s performance,
well look first at how it operates with conventional transformers, then at operation
with conventional transformers plus the Locomatic box, and finally at performance in
LocoMatic command mode.
Our test transformers in conventional mode included an elderly Lionel 125-watt LW, an
ALL Trol, an MTH Z4000, a Right-of-Way and a Lionel CAB-1 TrainMaster system. With all
transformers, the AEM7 responded smoothly and consistently to speed and direction
controls. When running the first Atlas O engine, the SW8/9, one has to have just the right
touch on the direction button or the engine is sometimes difficult to reverse; that was
not the case with the AEM7. In our tests, the new engine reversed absolutely reliably with
either the direction button or up/down movements on the throttle, on all of our test
transformers except the CAB-1. With the latter, the best procedure is to lower the
throttle until the engine stops, then use the DIR button to change directional states.
This is due to the way the CAB-1 functions, not to any oddity of the AEM7.
When throttled up from a dead stop, the sound system of the AEM7 comes alive at about 2
to 3 volts. Just before 5 volts, a brake release sound of escaping air indicates that the
engine is about to move and the motion begins at about 5 volts. A neat feature of the
Atlas engine is a slight amount of built0in momentum; no matter how fast the throttle is
advanced, the engine will accelerate somewhat gradually to the speed youve set. Once
we got the hang of it, we found a good way to get a smooth start was to advance the
throttle just slightly after we heard the brake release, wait a bit for the momentum
feature to start the train and then advance the throttle to road speed. With our
throttles, that started at zero volts (all except Lionel LW). This proved to be a great
way to smoothly start a train. If you ignore the wait, however, youll miss out on
what momentum can do. Even with the Lionel LW, which started out at nearly 8 volts, the
momentum feature prevented jackrabbit starts. However, to get the best out of this engine,
it should be run, with a transformer that ramps up gradually from zero.
the momentum feature does not appear to work on deceleration. When power was cut or the
throttle slammed shut, our test engines came to a very abrupt stopnot quick enough
to derail the train, but nearly so. I found this rather surprising, given the
engines two good-sized flywheels. A nice improvement on future engines might be to
apply the momentum feature on both acceleration and deceleration.
Speed range on the AEM7 is very good. Since this is a road engine, purposely geared
higher than a switcher, it wont absolutely creep with a load, but it will maintain a
very smooth low speed. Traveling light, the top speed of the AEM7 is almost fast enough to
derail on O72 curves. Adding a load of three to size Atlas passenger cars brings the tope
end down to about that of the prototype.
Using our standard test train of 72 MTH aluminum passenger cars, we found the
AEM7 could pull a maximum load of 15 cars. At that load, starting voltage increased to
nearly 18 volts and top speed was markedly reduced. With its single motor, this model
willof coursenot pull as strongly as a twin-motored engine, but it does have
all the power almost any operator would need. Pulling the Atlas O cars designed for it,
the AEM7 easily walked away with a six-car load. That' nearly 11'of train, as
much as most folks would probably want to run on their layouts.
The couplers on the AEM7 stayed firmly closed even when pulling the 15car maximum test
load. As delivered, the AEM7 starts in the "forward" mode when power is first
applied. However, the startup mode can be set to "neutral before forward" by
changing one of a series of six tiny dip switches located under the rectangular housing on
the roof. (The housing is easily removed by gently squeezing its sides.) Another dip
switch allows the engine to be locked in forward.
Performance: Conventional Mode with
Like most modern 3-rail locomotives with sound systems, the AEM7 has a small computer
aboard. And, like anyone designing a computerized sound system, the Atlas and Dallee
designers wrestled with how to allow the operator to access that computer. The folks at
QSI and MTH took one clear direction by limiting the operators input to throttle,
horn and bell controls; Lionel went another way with TrainMaster command, in which the
CAB-1 throttle allows input through an entire keypad of buttons, but only in command mode.
The Atlas O/Dallee LocoMatic control system occupies something of a middle ground
between. The LocoMatic box is connected into the two wires from any conventional
(non-command) transformer to the track. It acts as a passive "pass-through" box,
meaning it does not effect current or signals from the transformer to the track. However,
the box ads the capability of one-or two-button control of several features of the AEM7.
Most of its 10 buttons have a primary function as well as a secondary function when the
button is pressed at the same time as the "ALT" button.
Some LocoMatic features can also be controlled by the transformer, but other can only
be controlled by the box:
Sound functions include bell and horn, just like the transformer, and the ability to
turn off the main blower sound.
Lighting functions allow manual control of the front strobe lights of the normally
directional headlights and marker lights.
Coupler controls allow operation of either the front or rear coil coupler; this is the
only way to operate the couplers on the AEM7.
Direction controlsforward, reverse, slow and stopallow you to override the
normal forward/neutral/ reverse sequence and change direction or stop the engine from the
Speed, however, is still controlled from the transformer, in conventional mode.
How useful is all this? Direct control of the couplers using only one or two buttons is
a nice feature. I liked being able to turn on the strobeswhich are really
niceat will, rather than their normal method of operating only when the bell or horn
is sounded (which, however, is prototypical). I found independent control of the
headlights and red marker lights of doubtful use.
Push-button direction control is definitely more convenient than going through the
forward/neutral/ reverse sequence. However, since speed is still controlled by the
transformer, youve got to coordinate between the box and your transformer. In sum,
the LocoMatic box adds some useful features to conventional control, but its most exciting
features dont become apparent until you use it in command mode.
Performance: Command Mode with LocoMatic
From the beginning, Atlas O has explored the possibility of making its motive power
operable with TrainMaster command. The problem has been the limited interior space of the
engines Atlas has chosen to model: first the EMD SW8/9 switcher with its short, narrow
hood; now the AEM7. Remember that the Atlas O modus operandi is to stick to absolutely
prototype dimensions and offer cab interiors filled with engineers and interior details,
not can motors.
The AEM7 is about the same size as an F-3 diesel, but the AEM7 has two cabs and a much
shorter wheelbase, having precious little interior room for electronics. Although they
havent been able to fit a full TMCC system into the AEM7, the folks at Atlas O and
Dallee Electronics have, with LocoMatic, designed a system that fits on a single
electronic board and allows the AEM7 to operate as a full command engine on a TMCC layout.
In command mode, the LocoMatic box takes full control of the locomotive. Track voltage
is set at a constant 18 volts; changing two of the dip switches in the AEM7s roof
tell the engine to respond to command rather than conventional signals.
Now the Forward, Reverse and Slow buttons on the LocoMatic box act much like the
notches on a real locomotives throttle. Each momentary push of the Forward button,
for example, increases the forward speed a notch; each brief push of the Slow button
decelerates the engine a notch. Holding down a button moves through several notches
quickly. For panic stops, you press both Alt and Slow. This takes some getting used to,
but we found that with some practice, very smooth operation is possible. like a real
train, you can notch up to get the train moving, and then throttle back a bit to avoid
accelerating too quickly. Since this is a road locomotive with higher gearing than a
switcher, its easier to get smooth operation with a load than with the engine alone.
In command mode, all the other LocoMatic features operate as mentioned before. The
lights and sound system are always powered since theres constant voltage on the
The real fun of LocoMatic, however, is operating the AEM7 with other command-equipped
locomotives. We tested our AEM7 with a UCUB-equipped MTH F-3 including QS-3000 sound
system and found the units to be fully compatible. We were able to control the Atlas O
engine with the LocoMatic box and the UCUB-equipped engine with a Lionel CAB-1, completely
independently of one another on the same track.
For more information, on the Train America UCUB, which allows Installation of TMCC in
many locomotives, see review in Run 166 (June 1999). Also see the review of the QS-3000
sound system in conjunction with the UCUB in Run 169 (December 1999).
One caveat is that all command locomotives and all lighted cars on the same track as
the AEM& must be equipped with a small electrical device called a choke. About
1.75" long and .5" in diameter, the choke is inserted into either the hot or
ground line going into the engine or car. We found it a simple procedure to install a
choke in the hot line from the pick-up rollers to the UCUB and lighting boards in our test
Atlas O will be making the chokes available in two-packs with installation instructions
for $4.95, and customer support for installations will also be offered on the phone. In
our tests, we did find that a Lionel Command-equipped GP-9 without a choke,, when placed
on the same track as the AEM7, did seem to prevent the AEM& from receiving command
signals from the LocoMatic box.
Atlas tells us that a LocoMatic upgrade board, offering command control as well as
remote coil couplers , will be made available as an upgrade for its NW8/9 switchers. This
board will be standard equipment on future runs of the switcher.
Sound and Lighting
Recorded from the actual locomotive, Atlas AEM7 sound system has plenty of
volume, even when hauling a long train. The volume control is easily accessible by
removing the same housing on the roof that conceals the previously mentioned dip switches.
The bell sound is one of the nicest Ive hared on a modern locomotive, but the
horn is annoying, sounding shrill and electronic. The brake release sound, which signals
the engine is about to move, seems to be lacking bass, it may be that the speaker in this
engine needs better response at the low end. The blower sounds are accurate background,
but since we often think of electrics as virtually silent locomotives, the AEM7 sounds
right without the blowers as well.
The LocoMatic box nicely allows one to turn off the blower sounds. But unfortunately,
this also cuts out the bell and air brake release, leaving only the horn. Id have
preferred the ability to cut off only the blower, leaving the bell, brake release and
The Dallee-designed sound system relies on capacitors rather than a battery for power
when track voltage is cut, as when shifting between directional states. This eliminates
the problem of dead or low batteries, while still allowing the sounds to continue for
Lighting effects on this model are ver handsome. The constant voltage directional
headlights are nice and bright, and triple red directional markers illuminate the tail
end. Number boards are not illuminated because there was not sufficient space above the
cab to light both the boards and the markers. The strobes are particularly effective. In
prototype fashion, they go into action when either the horn or the bell is activated.
However, as mentioned earlier, the LocoMatic box can be used to activate them at any time.
Only the front strobes are illuminated; rear units are dummies. While some AEM7s had
ditchlights added in recent years, the Atlas O model with strobes only is accurate for
these engines as delivered.
Following the prototype, Atlas O illuminates its cabs only by the glow of the
instrument dials, which are back-lit by the headlight bulb. However, the cab detail in
this model is so good that some of us may want to add an extra bulb to show it off.
In sum, Atlas O has once again moved the ball forward with a very exciting product, and
had the guts too approach an important issue compatibility with Lionels
command systemin a new way. What a great combination for us to have in the hobby: A
parent company with 50 years of experience in HO and N scale manufacturing backing a young
O gauge division willing to take chances. This is good for the hobby, and we should all
wish them success. If we can keep generating that kind of excitement and new ideas, maybe
the next generation will be attracted to O gauge.
Prototype information on the AEM7 and ALP44 came from an article by Keith Thompson
in the June 1993 issue of Model Railroader, as well as from Jim Weaver at Atlas O. Thanks
also to Marty Fitzhenry, John Hughes and my son Nicholas Lewis for help in track testing