9 Jun 02
The ART-5490 is a Train Engineer receiver that is
intended to be mounted on board in a locomotive, tender, or trail
car to allow direct radio control of that locomotive. The receiver
works in much the same way as the trackside version of the TE
receiver, but it is much smaller which makes installation inside a
locomotive practical. The receiver can be powered from an onboard
battery, from constant DC track power, from PWC track power, or
from DCC track power.
The 5490 is rated at 2.5 amps continuous output current. I tested a recent production 5490 (Mar 99) and found that it would supply 5 amps into a 3 ohm resistive load. However, after about a minute it began to protect itself by intermittently shutting down. I decreased the throttle to 4 amps output and it ran steadily, although it did get quite hot. On the recent unit, there is a lead marked FAN coming from the unit which I suppose could be used to power a small fan to cool the unit. The instructions showed the fan wires, but failed to elaborate on the fan's necessity or specifications.
The 5490 accepts 12 to 22 volts of either polarity at its input and provides PWC power to drive one or more motors at its output. Unlike the 5471 trackside receivers, there is no linear output mode so that the 5490 MUST NOT be used with "coreless" motors such as in the LGB Chloe. It will work fine on most Large Scale locos.
The 5490 (at least the recent version) has a scanning receiver so that it will work on all 10 RF frequencies with the new 10 Frequency Train Engineer system.
The 5490 is about 1" by 1" by 3" without the optional external capacitor.
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One serious problem with conventional track power is that only one train can be run on one electrical block at a time. Over the years, many schemes have been devised to allow multiple trains to run more or less independently, but most of these schemes involve a lot of wiring and usually flipping a lot of switches to keep power routed properly.
A system called Digital Command Control (DCC) was developed where both power and control signals are delivered through the track to a locomotive equipped with a DCC decoder so that each locomotive could be powered and controlled independently on the same track. DCC has been pretty successful indoors. DCC is migrating outdoors as well.
The main drawback with DCC is that it is still pretty expensive. If you have a lot of locos, you can figure that you'll spend a couple of thousand dollars on a full up multiple cab radio walk around DCC system. Until just recently, DCC didn't include a wireless walk around control option. Some units are just becoming available, but they are really expensive, on the order of $200 to $500 per radio control link.
Using a 5490 from constant track power provides some of the functionality of DCC at lower initial cost. Track power has the advantage of being relatively inexpensive and provides nearly unlimited power and endurance capability. Lights and smoke can be run with no problem. In benign environments such as Southern California, track power works fine. Track cleaning is occasionally required, but it is really no big deal. In other environments, track power can be a major hassle which is why many outdoor railroads run from onboard battery power.
A loco converted to run on track power with a 5490 can later be converted to battery power without abandoning anything. A DCC equipped loco is going to run on track power only for a long time.
An example of a track powered installation of a 5490 in an FA/FB set can be found in my FA Tips page.
Using the 5490 with track power has some limitations.
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The 5490 is well suited for battery power operation. Most trains will run well at 12 to 18 volts which is in the range of the 5490's power input and that of readily available batteries. If the engine is large enough, both the battery and the 5490 can be mounted in the engine. A trailing box car is certainly large enough to hold a battery capable of several hours of operation and the 5490 receiver. Trail cars have the advantage of flexibility in that they can be hooked to several different locomotives. The downside is that you have to haul around a heavy car that cannot be cut.
The 2.5 amp capability of the 5490 is well aligned with battery power operation because a locomotive that draws more than 2.5 amps won't run long on batteries anyway.
There are no power interruption issues with battery operation so that the large storage capacitor is unnecessary.
There is
one issue that should be considered when installing a 5490 with
battery power. The 5490 uses a relay for reversing. It takes about
50 mA to hold the relay closed. If the motor is wired so that the
relay is held closed when the locomotive is moving forward, this
extra 50 mA will drain your battery faster. If you define "forward"
as the direction that you engine goes with the left button on the
TE transmitter pressed, the idle current of the 5490 will be
higher. At input voltages lower than 7.2 volts, the 5490 drops
out.
With the newer version 5490, the idle input current to the 5490 drops abruptly above 13.5 volts. If you run from a 12 volt gel cell battery, the 5490 will draw about 170 mA more idle current than if you use a 12 cell NiCad pack. I haven't formally measured idle current on an old version, but I don't recall it being that high at low input voltage.
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The mechanics of installation of the 5490 will have to be worked out for each different locomotive to determine where it will fit along with anything else that you want to cram in there. In any case, the motor leads will have to be isolated from all other wiring and connected directly to the 5490 motor terminals.
In both cases, you will want to suppress motor noise by installing a 0.1 micro farad capacitor across the motor leads and installing the Aristo supplied chokes in the motor output leads of the 5490.
Also, you will need to mount the code set button somewhere where you can get at it. For testing purposes, it is handy to mount the button and LED somewhere that you can see it from a distance.
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The 5490 programs similarly to the trackside versions, see my Programming the Train Engineer page for general programming information.
The 5490 differs a little in that the reversing delay can be set also. Once the receiver is linked as described in the programming tips page, you can press the A through E button within 3 seconds to set the delay.
Like the ART-5474 Remote Accessory Panel, the 5490 is sensitive to the distance between the transmitter and receiver during programming. If you hold them too close, the 5490 will overload and not receive properly. If the LED does not hold steady when you are pressing the code set button, move the transmitter away from the receiver. Full arm's length is usually good enough.
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The performance of the early versions of the 5490 is primarily limited by its range, which often isn't as good as I expected. There appear two major factors that limit the range, antenna placement and internal interference. Aristo and I agree that antenna placement is crucial in obtaining adequate performance from the 5490. On the internal interference issue, Aristo and I have agreed to disagree. Aristo claims that internal interference is not a problem, I claim that it is a major problem.
This internal interference problem was especially severe with the older units. The newer units seem to exhibit the same effect, but only to a minor degree.
Multiple engines each with 5490's installed can run in either direction on the same track. However, when two locos are linked to the same transmitter for use in an MU consist, special considerations must be made to run one of them backwards, such as in a typical double ended A-A consist. If you want a particular engine to run "backwards" then you must wire it to run backwards. The motor leads must be reversed. If you intend to run a consist together all the time, then this works ok. However, if you want to run an engine independently sometimes, then it would be better to install a DPDT switch somewhere to reverse the motor leads when needed.
The antenna wire of the 5490 must be left at its full length, stretched out as much as possible, mounted as high as possible and should not be folded back on itself. If there simply isn't room to stretch it out, excess wire should be coiled around a piece of 1" wide piece of cardboard. Proximity to the ground seems to have a significant effect. An engine that seems to work OK on the bench, often won't work well when set down on track that is on the ground. Route the antenna as high in the engine body as possible. A wire whip improves operation significantly but is visually unattractive and won't fit through tunnels.
With the newer 5490's it is possible to wire the antenna to a power pickup in either a battery powered to track powered installation. The antenna is DC blocked and filtered so that power pack and motor noise do not jam the receiver. With the antenna wired back to the track, the range of the unit is improved. In the battery powered case where I tried it, the range went from less than 15' to more than 50'. This is NOT an AristoCraft recommended procedure. Mine didn't blow up, but if your unit does, it'll probably not be a warrantable repair.
Note that when the antenna is wired back to the track in a track powered installation, the track noise more directly connected to the RX than in a battery powered installation. The radio range may actually be degraded over a regular antenna. In the battery powered configuration, the range has improved in every case that I have tried it (3 times so far). In the two "tri-modal" configurations where I could check the range in both battery power and track power modes, the range was good when using battery power and marginal to poor in the track powered configuration. I assume that this is because in the battery power case, there is only one connection to the track and the track noise is not actually impressed ACROSS the RX. In the track powered case, the internal ground of the 5490 is connected (through a couple of diodes) back to one rail. The antenna may be connected to the same rail or the other rail. In this case, the track noise may be impressed between the antenna and the 5490's internal ground and couple more strongly into the RX.
It may or may not be possible to do this with the older 5490. I don't have one handy as I write this to examine the RF input circuit. If you try it with an older unit (one with out the connectors for a fan and 5495), you do so at your own risk.
In my tests, I have determined that the older 5490 tends to jam itself. The receiver will receive commands reliably from 50' (as indicated by a steady indication on the LED) as long as the locomotive IS NOT MOVING. This is true no matter how I hold the transmitter or even if it is sitting right on the ground. As soon as I press the Fast button once so that the older 5490 starts making output power, the reliable control range reduces to less than 20'. This isn't motor noise because it will do the same thing when a power resistor is substituted for the motor. This will happen also with the 5471 receiver and the newer 5490, just not nearly as badly.
The newer version of the 5490 seems to have reliable control at 50' (the entire width of my backyard). I had an RS-3 splayed open waiting for a replacement DCC decoder after the original had been fried. I just connected the wires that went to the decoder to the 5490 without even using the Aristo supplied chokes. The antenna wire was just laid out on the walkway looping around the engine. The difference is control reliability between an old unit and the new unit was striking. If the original units had worked like this one, I would probably have stuck with them and not dabbled in DCC. As it is, I can use both systems together.
My definition of "reliable control" is that the receiver properly decodes EVERY command as indicated by a steady LED indication when a transmitter button is pressed. Flickering of the LED indicates that the receiver is missing commands. A few dropped commands are not much of a problem for single locomotive operations, unless you need to do an emergency stop in a hurry. I've experienced cases with the older 5490 where a loco would travel 10' or more before executing an emergency stop command.
In MU operation, dropped commands are disaster. If one locomotive in a consist gets a speed change command and the other does not, then the two locos will tend to run at different speeds. The only way to fix this is to bring all the locos to a full stop and try again. My net experience was that MU operation was not practical with multiple older 5490's due to unreliable commands.
I have been able to test MU operation with two FA's each with a new 5490 installed. With the newer units, I found that MU operations worked fairly well. As I ran the engines up and down in speed many times over a period of half an hour or so without actually stopping, they eventually started to buck each other just a little. Slowing to a stop and restarting resynchronized them.
This limitation is partly due to the fundamental design of the TE system. The TE system uses "relative" commands. This means that the transmitter issues a "faster" or "slower" command not knowing how fast the engine is really going. The receiver, however, remembers its last speed setting and increments or decrements speed as it gets commands. If multiple receivers are linked to one transmitter (as in an MU consist) and one misses a command, it'll remain out of sync with the other receiver until reset at a stop or until the other one misses a command too. This relative command method is necessary to limit the battery drain on the handheld transmitter so that the transmitter only draws power while a button is being pressed.
DCC systems get around this problem by issuing absolute speed commands. When you want to go speed 27, that command is continually issued to all decoders that are currently being addressed. If one decoder misses an absolute command, it'll hear it again in a few milliseconds or so and resynchronize to the other decoders before the impact is even noticed.
MU operation with 5490's is not as flexible as with DCC. The engines have to be wired to run in the right direction with respect to each other. With DCC, an engine will be added to a consist in the same direction as it was running when it was added. Two speed mismatched engines will not MU well with 5490's. DCC systems allow programmable speed tables such that every engine on the layout can be made (with some considerable programming hassle) to run at the same speed over the entire speed range.
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It is possible to control accessories, such as bell and whistle with the 5490. However, to do this with the older version requires that you dig inside it to pick up the control signals and build your own signal converter circuits. The work is not difficult, but doing so will ABSOLUTELY VOID your warranty and you do so at your own risk. If you are not electronically inclined it might be better to wait until Aristo begins shipping production quantities of the ART-5495 accessory board which can be connected to recent ART-5490's.
Headlights can be controlled with the 5495, but they will NOT be directional. If you want directional lighting, then the lighting will have to be wired from the motor terminals and then it will not be constant intensity.
This is the new 5490 attached to a 5495
accessory board. There is a 6" pigtail lead on the 5490 that
connects the two. The 5495 consists of five reed relays and the
necessary driver circuits. External connections are via the blue
screw terminal blocks down one side. These relays respond to the A
through E keys of the TE transmitter on the same address as the
5490. The A and B relays are momentary, the relay contacts are held
closed as long as the buttons are pressed. These would be
especially good for horn and bell control. Since they are reed
relays, there will be no interface problems with any sound system
that I know of. The C, D and E keys latch. Press the button once
and the relay closes, press it again and the relay opens. These
would be best used to operate lights, smoke or other accessories
that need to be turned on and left on.
Note that the relays used on the 5495 have reed contacts and cannot deal with very much current. There is no rating on them, but I would suspect that anything over 100 mA or so will weld the contacts together. If you want to switch a high current load, use an accessory relay with heavier contacts.
If you
have an old 5490 and want to use the accessory outputs, you can use
these diagrams to access the connections. This is a view of the
component side of the lower board in the 5490. The accessory
terminals are in a row down the right side of the board. The
letters correspond to which terminal is activated when a
transmitter button is pressed. If your unit has a storage
capacitor, its probably wired across the two lower terminals
labeled GND and +18VDC OUT.
The signals present on these terminals are commonly called TTL logic levels. This means that the voltages are near zero or near 5 volts and the terminals can source or sink only a few mA. To drive an accessory circuit, you MUST isolate the signals and possibly convert them to handle a little more current.
In the older units, the A and B outputs generate a pulse when activated. The C output toggles between logic high and logic low when activated. The D and E outputs stay high as long as a button is pressed. Note that on my two units, the D output didn't work. Since both units responded the same, I assume that this was a design problem, however since the old 5490 was never claimed to even have these outputs, the fact that one of them didn't work is not surprising or upsetting.
You can use one of
these two circuits to adapt the older 5490 control output to do
something useful. The top circuit is adequate to trigger a sound
system that might normally be activated by a reed switch. Note that
if it doesn't work the first time, try reversing the leads to the
sound system as the circuit is polarity sensitive. This circuit
would be useful on the A, B, D and E outputs.
To operate something that needs some current capability, use the relay driver circuit in the lower part of the diagram. This would be useful on the C output to activate smoke or lights that you would like to stay on until you turn them off.
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Since the
5490 can accept bipolar track power or DCC power at its input, it
is possible to wire an engine so that can run as a straight R/C and
battery powered engine, a straight track power engine, or a track
powered R/C engine. One way to do it is shown in the schematic.
The Power Source switch determines where the 5490 gets it power, either from the track or from a battery. The Motor Source switch determines where the motor gets its power, either from the 5490 or straight from the track. The Accessory source switch determines where the rest of the stuff in the loco (lights, smoke, sound etc) gets its power, either from the selected power source or from the 5490. The switches can be flipped in any order and nothing will blow up. On some locos, it may be difficult to find a spot to install 3 different DPDT switches. If you don't think that you'll ever use one of them, just leave it out and wire around it.
If the accessories are run from the track (with constant track voltage of some kind) or from the battery they will run at constant intensity, BUT, the headlight will be non reversing. If it was a reversing headlight anyway, it'll may either be on or off depending on the polarity of the voltage on the track or battery. If the accessories are run from the 5490, they will behave as they do with regular track power, the reversing headlight will work, but none of the lights will be constant intensity.
If you use "center off" type switches, then you can shut entire systems down. The power source switch then becomes a main power cutoff switch too. The motor switch can be set to disable to the motor only so that a sound system could be charged if it didn't run off the main battery.
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I had two early 5490's that I tried to use with constant track power. They didn't work out to my complete satisfaction in that application so they became surplus. I found that the 5490 makes a fine trackside receiver in lieu of a 5471 where the 2.5 amp capability was adequate. On the GIRR Mountain Division, I now use 5490's to power the inner and outer lines with excellent results. In this application, I can extend the antenna wire and I can't get more than 20' or so away anyway so that control reliability is excellent. The 5490's run from the fixed DC output terminals of MRC power packs. The packs are only 17 and 30 VA, but either one and it's 5490 runs a Shay with smoke just fine.
Note that if TE receivers of any kind are used for track power operation, there are some isolation issues that need to be considered. Multiple TE receivers can run from one DC supply ONLY if the outputs of the TE's are completely isolated. If you use a common rail power return, then EACH receiver MUST run from its own power supply. If you violate this rule, you will have short circuit problems.
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There were some problems with very early production versions of the 5490. Perhaps only a hundred units or so were affected and most of these were caught and fixed before they got into distribution. However, there is a possibility that if you got an early one, it might be affected.
This page has been accessed times since 30 Oct 1999.
