ATLAS O Home Page


This review is from O Gauge Railroading, January 2000. Reprinted with permission of Myron J. Biggar Group, Inc..

Atlas O AEM7/ALP44 Electric Locomotives

Review by Barry Lewis

Atlas O seems to believe "less is more." The company doesn’t treat us to a barrage of new products each year, but it does try to make each release stunning: A prototype that’s never been modeled in O gauge, superb detailing and pushing the envelope in a few ways. The AEM7, Atlas O’s first road locomotive, satisfies those criteria.


The AEM7 is the prototypical "little engine that could,." Created as Amtrak’s 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 built.

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. Amtrak’s 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’ frame—just over half the size of a GG1—is an engine that easily rivals the G in horsepower (7,000) and sustained top speed (125 mph). until Amtrak’s 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 ("7").

Amtrak’s original orders for AEM7’s 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 ALP44’s 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 occasion—so there’s certainly a prototype for modelers wishing to mix paint schemes.


Atlas O’s 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 O’s 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 prototype’s 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 it’s 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 Fitzhenry’s layout features working catenary made from Marklin components, and we found the Atlas O pantographs tracked perfectly on the overhead (although we didn’t rewire them to actually pick up current.) Marty says these are the first pantographs he’s 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 O’s model also features much better-than-average detail. The unique trucks are accurately reproduced with see-through areas around the journals. There’s 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 Amtrak’s lettering and stripes on the AEM7 would be a painter’s nightmare, but Atlas O carries it off perfectly. The borders between Amtrak’s 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 Amtrak’s 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; there’s 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 AEM7’s performance, we’ll 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 you’ve 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, you’ll 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 stop—not quick enough to derail the train, but nearly so. I found this rather surprising, given the engine’s 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 won’t 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 will—of course—not 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 LocoMatic

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 operator’s 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 controls—forward, reverse, slow and stop—allow you to override the normal forward/neutral/ reverse sequence and change direction or stop the engine from the LocoMatic box.

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 strobes—which are really nice—at 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, you’ve 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 don’t 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 haven’t 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 AEM7’s 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 locomotive’s 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, it’s 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 there’s constant voltage on the tracks.

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 F-3.

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 I’ve 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. I’d have preferred the ability to cut off only the blower, leaving the bell, brake release and horn.

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 several seconds.

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 Lionel’s command system—in 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 these locomotives.

Now Shipping || Locate Dealer || Online Catalog
Contact Atlas O || Forum || Layouts || Product Reviews
Order Catalog
|| Become A Dealer || Atlas O Home Page

All information 1998 Atlas O, LLC