Frequently asked questions


My locomotive stalls intermittently. What should I do?

Most stalling issues and resulting loss of power is caused by dirty tracks or equipment. Microscopic dirt, debris and corrosive forces of nature over time can cause your track and locomotive wheels to gather grime and loss of contact for short periods, resulting in less than optimal performance of your locomotive. LocoFi™ decoders are equipped to help you tide over the smallest of these issues, with the help of an on board capacitor that keeps the decoder "alive" during such short interruptions. However, to avoid the longer power interruptions causing the board to cut out, here'a list of few recommendations we have gathered over time to help with such issues:

  1. "Dirty" the track some more. While we all know keeping the tracks clean using various methods like rubbing alcohol, cleaning car, etc., it eventually becomes a regular maintenance routine. What we have found instead is that the conductivity improves far more by spreading a conductive material like fine graphite over tracks than actually cleaning them! Further, once it's all over the tracks, the tracks are prevented from getting oxidized by air, micro sparks, etc. leading to a longer lasting effect such that you don't have to do it again and again that often. See the links below for more info:
  2. Make the wheels smooth and shiny. This is especially true with sintered wheels of Athearn BB types. Read the following wonderful link (there's a link to even more wonderful video in there by the author) and run your loco on graphited track (see above) for ultimate results:
  3. If you are still having issues, the next weak chain in the link is the pickup wipers or the contact points from the wheels all the way to the soldered wire joint. For such cases, the best solution is to use a drop of conductive lube at such joints after cleaning them thoroughly. This will ensure that even if there is something loose in that assembly, the conductive lube will keep it conducting.
We plan to offer our holy grail to the problem by offering Amrit™ very soon. Until then, commercially available backup power solutions will work well as well. Please see our other FAQ -> General -> 05 for details.

I get loud static buzzing from speaker as soon as power is connected. What is going on?

Are you using an older DC power pack? Some older power packs put out what is called "rectified AC" which is not pure or "clean" DC. We highly recommend using a high amperage "clean" voltage regulated power supply to achieve maximum performance. Alternatively, a suitable electrolytic capacitor at the output of the "rectified AC" power supply can filter out most of the "noise". Please watch this video to learn more on how to do this. WARNING: Please heed all precautions while working with high capacity high voltage capacitors. Connecting them with incorrect polarities can lead them to vent off gases and splatter liquids, sometimes even causing explosions. Capacitors are energy storage devices and their improper use can lead to serious injury. We recommend connecting a bridge rectifier rated for suitable voltage and current (e.g. KBP310) and 4700uF 50V electrolytic capacitor. See schematic below.

I have tried multiple times but can't add my loco to the network. Why?

There can be several reasons for this. Please download our Android Connectivity Issues guide that will help you get past these.

Why did my sounds stop working suddenly after a 'Factory Reset'?

While we have not seen it, but because a couple of customers seem to have reported this issue, especially after a 'Factory Reset', here's how to get the sounds back.

  1. Take the microSD card out. See how to here: Replacing microSD card. WARNING: Please make sure that the module is not powered during the entire time working with the microSD card. Please power off the module before taking the card out and power it back up only after the microSD has been properly seated and its cover locked in place.
  2. After plugging it into the computer (you may need to use the supplied SD card adapter), copy the contents of the microSD over to a temporary folder on your computer.
  3. Download the SD Formatter software from here: Use ' Overwrite format' option while formatting the microSD.
  4. Copy the files from the temporary folder back onto the microSD.
  5. Replace and lock the microSD back on the module.
In case the sounds don't start working again, it maybe that the sounds files themselves are possibly corrupted. Please copy the original sound files onto the microSD. If using factory default sounds, please contact us and we will be happy to provide the original sounds again. In the rare event, it's still not fixed and the module is under warranty, it may need repair/replacement. Regardless of warranty, please contact us to see if any more troubleshooting needs to be done in your unique case to fix the issue.


How do I find out the polarity of a LED?

Scenario 1: Included LEDs - LocoFi comes included with some spare LEDs with leads. There's two ways to identify the polarity (see picture below)
1. The longer lead is positive (anode).
2. If viewed from top, the flatter side is negative (cathode).
Scenario 2: Pre-wired LEDs - If your loco comes pre-wired with LEDs, connect a 3V battery (a 3V coin cell or 2 AA or AAA in series), (see picture below) across the LED terminal wires briefly. If it lights up, the battery + is the anode. If it doesn't light up, it's the cathode. In the latter case, try reversing the battery polarity to double check if it indeed lights up and is not a result of poor connections. NOTE: Please note that the LED terminal wires have been desoldered from the light board / DCC ready board and not part of any other circuit. You don't need to take out the LEDs themselves from their sockets. Also, if the LED being tested is RED or GREEN in color, it may be a good idea to put a small resistor (about 100 ohms) in series to avoid burning it out.

How do I isolate the motor?

Let's start by answering a few questions. What is motor isolation?
DC powered locos get their power directly from the track to the motor. The locomotive speed is controlled by varying the voltage/current on the track. This is evident in the brigtness of the ligts that changes when the speed varies. Motor isolation is essentially cutting off the power to motor going from the tracks. Why is it important?
When we install LocoFi™ decoder module, we are handing over the motor control to it. The decoder module will in turn get the power from the tracks / rails and the motor will be programatically controlled by the microcontroller unit present on the baord. This opens up a whole set of possibilities the way you can make your locomotive run. How do I do it?
There's many ways do it depending on the wiring inside the locomotive. First step is to find out how the current is flowing all the way from right track to left track passing through the motor. Second step is to determine which point the power to the motor be cut off. This may involve some out of the box thinking. It must be done in a manner so that the track power can susequently be easily fed into the decoder and the motor output wires from the decoder easily feed into the motor. While there may be patterns around doing it for each locomotive type manufactured in a particular era, it is next to impossible to document all the various types. We strive to produce video content demonstrating the same as and when possible. Please check out videos section to see how this is done in some most pupular types e.g. the old blue box Athearn, Tyco, etc. Also, please check back regularly or subscribe to our YouTube channel to get periodic updates as and when new content is published. PRECAUTIONS: Once motor isolation is done, please ensure by double checking that there is no power whatsoever being fed to the motor directly from the tracks. Otherwise, it may result in shorting the circuitry of the decoder and render it unusable. This is not covered under warranty. One way to check this is to do the continuity test with your multimeter all the while turning the trucks around in all directions (up, down, right and left) to ensure that all paths are open. If in doubt, please do not hesitate to contact us at any time during installation. We will do our best to help you out.

LocoFi™ Technology

How is LocoFi™ different from DCC?

LocoFi™ and DCC are completely different technologies as explained below: 1. Power: DCC equipped locomotives run on DCC powered tracks only. LocoFi™ equipped locomotives can run on
a. DC powered tracks (9V – 24V “clean” DC).
b. DCC powered tracks.
c. Battery power whether onboard (dead rail) or powering the track. LocoFi™, using what today’s latest technology allows us to do, is designed from the ground up to fit into your world, instead of offering just another “technology solution” which comes with its own set of limitations that you have to work around or eventually compromise with. 2. Control mechanism: DCC equipped locomotives can be controlled by proprietary DCC controllers only. Some DCC manufacturers are, finally, offering smartphone apps to control their locomotives. However, that still requires the purchase of “command station” at least, and the wiring to go along with all of that to begin with. LocoFi™ equipped locomotives on the other hand are controlled by the controller that you already have, i.e. your smartphone, using the LocoFi™ app available for download on Android play store. iPhone app is on the roadmap. Again, one of the key driving principles behind LocoFi™ is to fit into your current technology world, by leveraging the existing hardware and computational power already ubiquitous in all of our lives, instead of offering another "technology solution" that is not agile enough to evolve with the changing technological landscape. 3. Communication mechanism to exercise Control: DCC equipped locomotives use a very specific, but standard and openly available protocol. This protocol is quite similar to a Morse code mapping of pulses of current. These pulses of current are analogous to 0s and 1s used in micro-computing, and hence the “digital” in DCC. LocoFi™ equipped locomotives use WiFi as the radio wireless local area networking standards to control locomotives. WiFi powers and supports many key components of today's technological landscape, including the internet - be it at home, work or club. By using WiFi as the key communication protocol, LocoFi™ is able to offer a mature and robust technology platform, while weaving into your existing technology infrastructure.

How does LocoFi™ work?

LocoFi™ is an ecosystem that consists of:
a. LocoFi™ modules with powerful hardware and firmware with onboard customizable sound that you install in your locomotive, and
b. LocoFi™ app that you run on your smartphone to control the locomotive
Simply install the LocoFi™ module in your locomotive and control it with your smartphone or tablet as a throttle.

What do I need for the set up?

  1. Install the LocoFi™ module in your loco. You will need to solder 7 wires (or get them done). Detailed instructions and install videos are provided. We are always available via e-mail/chat for any further help. Bonus: you don't need to wire your layout.
  2. You will need power for your locomotive, clean (NOT pulsed) DC, DCC track power or battery. See our other FAQ -> Troubleshooting to learn how to clean "pulsed" power.
  3. (Optional) An access point (or home router) if you want to set up a network of locomotives or need extended range ( internet connection not required). For a single loco to be managed from one device, you can go direct WiFi i.e. straight from your smartphone to your locomotive (no router needed). In case you don't have one, most can be purchased for less than $25.
  4. Your smartphone or tablet as a throttle. Again, in case you don't have one, most Android or FireOS devices can be purchased for less than $50. No cellular connection required.
  5. Occassional internet connection to only download the app ( FREE) and subsequent updates ( internet connection NOT required to run the trains).

Is LocoFi™ a proprietary system?

We'll answer this with another question. Can a system based on open standards, open source platform, that runs on millions of devices, that does not require custom setups, custom equipment or even custom power supplies, is based on ubiquitous 802.11 standards AND runs on most layouts supporting multitude of voltages be called proprietary? You can answer it yourself. Did we mention that LocoFi™ does not tie you up with its own proprietary sounds either. To put it in other words, LocoFi™ does not require custom equipment to operate and that is where interoperability standards come into picture. The LocoFi™ app can run on literally millions of devices that is most likely already in your pocket (no separate purchase necessary; trying to use existing powerful hardware at hand). LocoFi™ does not need custom power supplies. Any clean DC power supply with a wide range of choice of voltage will do (even your old laptop power supply will do; again FREE). You can even use your old DC power pack/throttles with some modifications (see our other FAQ under Troubleshooting). Again, so much to choose from. The same goes with WiFi router or the access point. Use any brand of WiFi router out there and again most likely in your home/club setup without a need for internet connection. Bonus: Setup your LocoFi™ module to act as an access point to form a network of upto 8 devices OR use your smartphoen itself to act as an access point (aka portable hotspot) and use it to run trains too! Can a smartphone operate LocoFi™ and say a DCC decoder equipped train? Yes. Can a DCC throttle operate LocoFi™? No. However, we provide APIs that anyone is free to implement to operate LocoFi™. The only requirement is that device should be WiFi capable and that is a capability present in many more devices (including the newly released DCC throttles if you REALLY want to go that route).

You need a $1,000 phone to control trains! What a bargain!

:-) We keep emphasizing it, that a "smartphone" is a (handheld) computer with maybe a phone functionality built into it (without phone it is called a tablet). With that said, they do come in various shapes, sizes and prices. They can cost for less than $50 (mostly Android and FireOS devices and cost less than a handheld throttle or even a power pack in some cases) to (yes) upwards of a $1000. It's up to you how fancy you want to go. You only need a $50 one run trains. But if you're looking for NPU (Neural Processing Unit) in a "smartphone", it will cost you more. So, you pick your bargain. BTW, whatever the cost, most likely it's in your pocket so you don't have to really spend even the extra $50 :-). To summarize, smartphone was invented because it was possible to miniaturize computers to handheld devices to carry out various tasks through programs called apps, pack in features of a camera, ability to make phone calls and other sensors that could provide useful information on the go.

A phone is a phone! You can't replace a handheld train controller with a phone.

Yes. Finally you can! First, as we mentioned earlier, a "smartphone" is a powerful computer (packed with more than 6 billion transistors, it's more powerful that the mainframes of the '70s). It may or may not have a SIM card to make cellular calls and we don't even need that to run trains. With LocoFi™, smartphone app is the controller. The SmartThrottle™ as it's called is unlike any other throttle app you may have used before. With features like haptic controls, you just notch up and down the throttle without having to look at your phone (unless of course you want to see the speedometer :-) to keep a check on the speed). The throttle slider on the screen will vibrate and/or sound (as if you're in a real loco cab) for each notch up and down just like you're in a loco cab. You can always turn these settings off. It's time to quit the knob and hit the notching that is customizable with number of speed steps of your choice. A smartphone is integral to how LocoFi™ enables wireless control and is the only controller you will ever need.. It all comes down to software. A touch screen based device packed with all kinds of sensors cannot be compared to a handheld throttle. Audible cab sounds for features like light switches, reverser, throttle, etc. give you close to a real feel. Apart from the haptic controls, there are control buttons that are customizable to activate only on applying certain pressure, sliders and toggle switches to configure and customize the app and/or the locomotive. With all these features you will not go back to handheld throttle again. Moreover, LocoFi™ app is available for FREE download for Android and FireOS devices. That makes millions of devices as potential candidates for a controller. Of course, if you have had experience with a poorly designed app software in the past that is non-intuitive with clumsy touch screen buttons and requires you to constantly look at your screen, it's no surprise you will think twice before trying another app based train control.


Why WiFi (and not Bluetooth)?

The decision about using WiFi vs Bluetooth for communication was the first in the early design phases of LocoFi™. In fact, Bluetooth solutions were already available while we were still working on WiFi based LocoFi™.

  1. WiFi and Bluetooth are two wireless technologies that both operate on the 2.4GHz spectrum but the underlying protocol is very different.
  2. Bluetooth was invented specifically for exchanging data over short distances while WiFi was intended as a replacement for wired LAN (Local Area Network or Ethernet).
  3. Bluetooth is meant for exchanging small amounts of data only.
  4. Bluetooth speeds are much slower than WiFi. Think video transfer (Bluetooth can't support it).
  5. Since WiFi is a wireless extension of the internet, it seamlessly ties into IoT. Think about cloud and the ability to run your trains on a remote layout (even across the world) or stream your cab video to the world.
  6. Only WiFi can handle a large network (think internet) of locos very easily (though you can run direct WiFi too that feels like Bluetooth but with much higher speeds).
Bluetooth is essentially useful to connect nearby devices to exchange small amounts of data for example in your car or your headset. Still not convinced. Google "WiFi vs Bluetooth". You will find plenty of information with pros and cons of each technology. It will be easy to see why WiFi is better suited over Bluetooth for model railroading operations.

Can I use battery (aka deadrail) to power LocoFi™?

Yes. Absolutely. Since the LocoFi™ module can be powered by DC, a battery qualifies as a very good source of DC. While we do not sell batteries (at least not yet), if you have a battery pack rated for anywhere between 9V - 24V powering the module directly, the LocoFi™ module will perform flawlessly without even any concerns for dirty track. In fact, minimum operating voltage for LocoFi™ 2 - Next Gen (DDLLHB) is 7V and can easily run off of 2S LiPo. Please check out our videos of a LocoFi™ equipped locomotive operating with power from an onboard battery and another video showing a track powered by a battery.

Why are LocoFi™ NMRA color coded wires not DCC compatible?

DCC was invented as a standard for compatibility among DCC equipment manufacturers. LocoFi™ is NOT DCC. DCC ready boards are just that, "DCC Ready" only. It's a clever way to let a locomotive run on DC when the DCC decoder isn't installed. To make LEDs functional on DC, we need resistors and that is pretty much the DCC ready light board does. That means the LED resistors can't be onboard the DCC decoder to make in plug'n'play or you would be desoldering the SMD resistors from the light board. In an ideal world, an 8 pin connector would be just that, an "8-pin connector". You plug in anything into it, be it a DCC decoder or a LocoFi™ module. Alas, with pretty much only DCC around until now, the choice for model locomotive manufacturers was obvious. That is, to design a DCC ready board in a way that runs on DC power as well. The 8 color coding scheme only specifies "common". It's the DCC standard that specifies that "common blue" should be positive. How does it impact LocoFi™? Well, not much in a way. The LEDs are diodes meaning they conduct electricity in one direction only. Hence, all we need to do it feed the blue wire on the LocoFi™ module to negative side of the LED instead of the positive. Worst case (opposite polarity), the LED won't light up. Please note that a module is complete in itself by having resistors onboard or else you need external circuitry to light your LEDs which in the case of DCC is provided by locomotive manufacturers. Still confused? Questions? Please feel free to Contact Us.

Why can't LocoFi™ modules plug into the 8 pin connectors on the DCC ready boards?

LocoFi™ modules can operate on voltage as low as 7V (for DDLLHB) and as high as 24V. That's a lot of flexibility. Much more types of power supplies to choose from. Sometimes, no standards is the best standard. To make LocoFi™ modules compatible with DCC ready boards, we'll be giving up this flexibility to "run anywhere". We'll have to get the onboard resistors out and for those folks with DC only locomotives who have been waiting for this revolutionary technology to arrive would be soldering the resistors as well, not to mention that they won't be able to use the variety of voltages to run on or risk burning out the LEDs. Other than that, switching around the comomn blue to positive isn't a big deal. We just don't want to give up the power we want to give to our users. Simplicity and flexibility! Please note that we don't provide the 8 pin connectors or else it may be mistaken for DCC plug compatibility and risk destroying the LocoFi™ module. We do hope that in future, model locomotive manufacturers will provide more generic 8 pin adapters that can take in "any" module.

Can I use LocoFi™ for any other scale but HO?

Let's look at a LocoFi™ modules as a devices with different sizes and capabilities especially the motor current rating. Please check out the technical specs of each module for details. Then look at your requirements. If you find a LocoFi™ module that matches your requirements (size, current rating, etc.), then it's good fit. It's true that we mention "for HO" in some of our product titles but that's just there to emphasize the best suited size and current rating for a typical HO scale loco. Obviously, a smaller size can always fit inside a larger scale loco and vice versa too in some limited cases. In fact, LocoFi™ powers our customers' equipment of all scales from N, HO, OO, On30, S, O and G. As we release more optimized versions for other scales, they will have their own specific "best suited for" scale mentioned in the product title. Also note that barring things like dimensions, current rating, sound output volume, etc., all LocoFi™ products still work on the same underlying technology with a single application controller app. You may as well be operating a G scale and an HO scale loco running on two different layouts at the same time as long as they are added to the same network!

Can LocoFi™ work with AC?

Most electronics need DC power supply. Even a DCC decoder rectifies the DCC signal to draw power for its operations. So, yes, AC can be rectified, filtered and fed to the LocoFi™ module. There are two ways this can be achieved. One, put the bridge rectifier and the filter capacitor with the LocoFi™ module in the loco shell. However, the filter capacitor is usually a large component that may not fit inside the shell of a HO scale loco. It may be more feasible in S scale and O scale (or any larger scale). The other way is to rectify and filter the AC power supply before it's fed to the tracks. That way, it's very similar to running on older "pulsed" power supplies (see our FAQ -> Troubleshooting). This means that no other AC only operated trains can be run simultaneously on the same track.

Can commercially available supercapacitor solutions work with LocoFi™?

Yes. While the much awaited Amrit™ is delayed, currently commercially available 3rd party "charging from the track" can work equally well. Be it a battery based or supercapacitor based, as long as you put them in series at the output of a bridge rectifier and ensure that the rated voltage at the track isn't exceeded, they can do the job. Please see the wiring diagram below for reference.

What's the range of the WiFi signal?

The range of the WiFi signal is determined by the transmit power, the receiver sensitivity and any RF signal attenuating obstacles in its path. FCC regulates the transmit power while the receiver sensitivity can be increased by adding external antenna. Clear line of sight can easily give range upto 300 ft. But hey, why bother with these worries when you can simply setup a mesh network of access points and take the signal with you wherever you go. It's that simple! Really!

Will LocoFi™ work inside a metal enclosure?

Short answer. Yes but the range might be limited. Long answer. As long as there is some opening where the RF signal can leak through, there will be no issues. However, the range may be limited. It's similar to how much your eye can see sepending on the amount of light available or just like when talking on your phone your cellular signal drops when you walk inside some buildings. We've performed laboratory tests by enclosing the entire module in aluminium foil based containers and as we created small openings, it worked just fine. In fact, the WiFi microcontroller itself is enclosed in a metal case (to avoid external RF interference) and only the PCB antenna is exposed for transmission and receiving data. See below:

Does LocoFi work with Amazon Fire devices?

Yes. It is supported on all compatible versions of FireOS that is supported in Android. For Android, we currently support 5.0+. Please see Fire Tablet Device Specifications to see compatible Fire devices and FireOS versions.