Is it possible to have a non-rotary (i.e. blinking LED light) beacon on the tops of locomotives in N scale?
What peaked my curiosity was an advertisement for blinking LEDs that did not need an integrated circuit board to blink. You just hook them up to a power source, and you're golden.
How was something like this be hooked up to a Kato N scale SD40-2 with the DCC decoder?
The blinking LEDs are just regualr LEDs with a blinker circuit integrated into them. I haven't seen any that would be small enough for N scale, most of them are too big even for HO. A seperate blinkign circuit would allow uou to use tiny surface mount LEDs int he beacon, which are small enough for N scale - of cource you need to find room for the circuit.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
What is the prototypical size of a beacon in real life and in N scale?
Say I bought a very, very small surface mount LED. Where would I hook up the power wires in an N scale engine that has a drop-in DCC decoder? What about hooking up the wires to the black and red leads from the track pickup (i.e. 14.1V from the track in a DCC system)?
gatrhumpy What about hooking up the wires to the black and red leads from the track pickup (i.e. 14.1V from the track in a DCC system)?
What about hooking up the wires to the black and red leads from the track pickup (i.e. 14.1V from the track in a DCC system)?
The LED would make a very brief flash and be immediately destroyed. An average LED requires no more than 1.2 to 3 Volts at only 15mA or so. The 14 Volt square wave DCC track power would cause it to burn out instantly without a current limiting resistor in the circuit, usually in the range of 1,000 Ohms. I know of no surface mount flashing LEDs -- most are 3mm or larger. I've even known of cases where an LED would explode with a very loud pop and throw shards of plastic for a long distance when connected to the wrong voltage.
If the decoder inside your locomotive has the capability of connecting additional lights and can be programmed for a flashing beacon, an LED could be connected to the decoder's function output, but this, too, is going to require a resistor or you could destroy the decoder as soon as you turn on the beacon. In order to do this, you must determine exactly what type decoder is in the loco and then read through the decoder manual to see if it can be programmed for a flashing beacon and which function wire is available. You need to also be aware that an LED is a polarity sensitive device, and if you get the wires backwards it won't work.
Thanks for the reply.
I have the MRC 1806 sound and motor DCC decoder for the Kato N scale SD40-2. It's a board, so not sure where the hookups would be for extra lights and whatnot. Guess I'll have to check.
It can't be done -- the MRC 1806 does not have any light hookups other than the headlight.
You might want to take a look at what Ngineering has to offer.
What if I soldered the N8032 beacon simulator to the headlight LED connections on the board (i.e. in parallel)? Would that work?
Not exactly. It can be wired in parallel to the LED, but there will be a current limiting resistor on the decoder for that LED and the N8032 would have have to be wired in before the resistor.
I've never tried wiring two LEDs that way, but my opinion is that each time the strobe turns on or off the headlight LED would get dimmer and brighter due to the current being drawn away from it. This may also overload the headlight function output of the decoder and shorten its life.
This is copy and pasted from the above website:
Installing the N8032 is very straightforward. Its tiny size and thin construction will allow it to be placed in many spaces too small for even the smallest Z-scale decoder. Because the module has circuitry on both sides, care must be taken to be sure that the components or wires soldered will not make contact with any metal object (such as a locomotive frame) causing a short circuit. If the N8032 is to be used in a stationary (not track powered) application, it can also be powered by any well-filtered and regulated DC power source with an output of 6-18VDC. Included with the module are two 6” lengths of #32 insulated wire. If necessary, these can be used for power input wires. Most wired decoders have a blue wire which is the common connection for all wired functions (F0, F1, etc.). It is the + DC connection and will be connected to solder point #1 as shown in Fig. 1. If the decoder is a “drop-in” style without wires, consult the decoder manual and use the blue wire supplied to connect point #1 to the appropriate + solder pad.
Installing the N8032 is very straightforward. Its tiny size and thin construction will allow it to be placed in many spaces too small for even the smallest Z-scale decoder. Because the module has circuitry on both sides, care must be taken to be sure that the components or wires soldered will not make contact with any metal object (such as a locomotive frame) causing a short circuit.
If the N8032 is to be used in a stationary (not track powered) application, it can also be powered by any well-filtered and regulated DC power source with an output of 6-18VDC.
Included with the module are two 6” lengths of #32 insulated wire. If necessary, these can be used for power input wires.
Most wired decoders have a blue wire which is the common connection for all wired functions (F0, F1, etc.). It is the + DC connection and will be connected to solder point #1 as shown in Fig. 1.
If the decoder is a “drop-in” style without wires, consult the decoder manual and use the blue wire supplied to connect point #1 to the appropriate + solder pad.
Figure 1
If the solder pad has a resistor in series with it, be sure to connect the blue wire behind the resistor (see Fig. 2). This will ensure full voltage is supplied to the module.
Figure 2
Important note: A low-wattage iron with a pointed tip should be used for connection of wires. Too much heat or solder can easily damage the wires, decoder or module and void the warranty. Also, all connecting wires should be pre-tinned before soldering them to the module. This will make connection quick and easy and ensure excessive heat is not applied to the solder points. Next, choose the function you want to control the N8032 module and connect the appropriate function wire to solder point #2. For example: If you want F1 to turn on the Beacon, connect the green wire to #2. Again, if the decoder is the drop-in style, use the enclosed green wire to connect the appropriate function solder pad to #2. Make sure the pad chosen for this connection is not a “+” pad , but a function pad (– DC connection). Whichever function you choose, make sure it is programmed for On/Off control only. Do not program the function for special effects. The N8032 will control the special effects. Direct Track powering (without a decoder connection) All of our Simulators require a clean DC voltage of known polarity for their power source. Track power is typically provided in one of two forms. DC voltage (analog), or DCC. Analog track power has been around for more than 75 years. Simply put, a DC voltage is applied to the two tracks with one being +DC and the other, -DC. Increase the voltage and the electric motor in the locomotive spins faster making the train go faster. If the train is required to reverse, track polarity is reversed so the loco's motor turns in reverse. Also, what defines "forward and reverse" is dependent on which way the loco is facing when it's put on the track. Bottom line here is that track polarity is not fixed. Our Simulator needs fixed polarity. DCC track power is such that to devices requiring plain DC voltage, it looks like AC power. That is because voltage levels on each track go both + and – continuously. The DCC decoders in locomotives “descramble” the track signals and provide correct polarity so their motors can function normally. It is this process that will allow multiple locomotives to go in different directions on the same section of track, at the same time (a feature not available with analog track power). Once again, our Simulator needs fixed polarity and it needs to look like DC voltage. Due to our Simulator's very small size, there is insufficient space to include additional circuitry and components necessary for proper power conditioning when direct track pickup is to be used. There are two solutions to this problem and both are inexpensive: Discrete components The Simulator can be powered from the track with the addition of two readily available components: a bridge rectifier (our N301S or N302S will work just fine). If DCC operation is used, the addition of a filter capacitor (10μf or larger and minimum 16-volt) will be required. Figure 3 below is schematic diagram of the connections required. Figure 3 This is the least expensive solution, but is has a couple of minor drawbacks. First, the bridge rectifier (and capacitor, if needed) are not mounted on a circuit board so direct solder connection is required and you will need to ensure the pins on the rectifier and leads on the capacitor (depending on the type of capacitor) are organized so that they won't short out against anything. Second, depending on the physical size of the bridge selected (and capacitor, if needed) and the scale you're modeling, hiding these additional components so they're not noticeable can be a bit of a challenge. N8101 DC Power Source A more elegant, but very slightly more costly ($3.95) solution would be to use our N8101 DC Power Source. It has all of the components needed, includes a circuit board with solder points, is extremely tiny (1/2 the size of our Simulator), has the lowest possible voltage loss (important for analog operators). Click here for more information on the N8101. Figure 4 below is schematic diagram of the connections required. Figure 4 Connecting LEDs When connecting the LED, proper polarity must be observed. LEDs are “polarity sensitive” and will not function is connected backwards. The N8032 is configured to connect to a 20 ma LED with a device voltage of 1.85-2.0 VDC. This covers all of Ngineering’s Micro and Nano yellow and red LEDs, as well as many of the yellow and red LEDs available. Using wire appropriate for the size of the LED and its placement in the locomotive, connect the LED cathode (the – connection) to point #3 on the module and connect the LED anode (the +) to solder point #4. If desired, a series-wired pair of LEDs can be connected in place of the single LED (see diagram of our Early-era Alternating Flasher for an example here). By doing this, this module will support 2 LED beacons (flashing simultaneously). When using a series-wired pair of LEDs, the individual intensity (brightness) of these LEDs will be slightly lower than that of a single LED connected to the same solder points. This completes connection of the N8032 module. It is recommended that a thorough re-inspection of all connections and module placement be performed prior to applying power to the locomotive. We hope you enjoy the added realism our module provides.
Important note: A low-wattage iron with a pointed tip should be used for connection of wires. Too much heat or solder can easily damage the wires, decoder or module and void the warranty.
Also, all connecting wires should be pre-tinned before soldering them to the module. This will make connection quick and easy and ensure excessive heat is not applied to the solder points.
Next, choose the function you want to control the N8032 module and connect the appropriate function wire to solder point #2. For example: If you want F1 to turn on the Beacon, connect the green wire to #2.
Again, if the decoder is the drop-in style, use the enclosed green wire to connect the appropriate function solder pad to #2. Make sure the pad chosen for this connection is not a “+” pad , but a function pad (– DC connection).
Whichever function you choose, make sure it is programmed for On/Off control only. Do not program the function for special effects. The N8032 will control the special effects.
Direct Track powering (without a decoder connection)
All of our Simulators require a clean DC voltage of known polarity for their power source. Track power is typically provided in one of two forms. DC voltage (analog), or DCC.
Analog track power has been around for more than 75 years. Simply put, a DC voltage is applied to the two tracks with one being +DC and the other, -DC. Increase the voltage and the electric motor in the locomotive spins faster making the train go faster. If the train is required to reverse, track polarity is reversed so the loco's motor turns in reverse. Also, what defines "forward and reverse" is dependent on which way the loco is facing when it's put on the track. Bottom line here is that track polarity is not fixed. Our Simulator needs fixed polarity.
DCC track power is such that to devices requiring plain DC voltage, it looks like AC power. That is because voltage levels on each track go both + and – continuously. The DCC decoders in locomotives “descramble” the track signals and provide correct polarity so their motors can function normally. It is this process that will allow multiple locomotives to go in different directions on the same section of track, at the same time (a feature not available with analog track power). Once again, our Simulator needs fixed polarity and it needs to look like DC voltage.
Due to our Simulator's very small size, there is insufficient space to include additional circuitry and components necessary for proper power conditioning when direct track pickup is to be used. There are two solutions to this problem and both are inexpensive:
Discrete components The Simulator can be powered from the track with the addition of two readily available components: a bridge rectifier (our N301S or N302S will work just fine). If DCC operation is used, the addition of a filter capacitor (10μf or larger and minimum 16-volt) will be required. Figure 3 below is schematic diagram of the connections required. Figure 3 This is the least expensive solution, but is has a couple of minor drawbacks. First, the bridge rectifier (and capacitor, if needed) are not mounted on a circuit board so direct solder connection is required and you will need to ensure the pins on the rectifier and leads on the capacitor (depending on the type of capacitor) are organized so that they won't short out against anything. Second, depending on the physical size of the bridge selected (and capacitor, if needed) and the scale you're modeling, hiding these additional components so they're not noticeable can be a bit of a challenge. N8101 DC Power Source A more elegant, but very slightly more costly ($3.95) solution would be to use our N8101 DC Power Source. It has all of the components needed, includes a circuit board with solder points, is extremely tiny (1/2 the size of our Simulator), has the lowest possible voltage loss (important for analog operators). Click here for more information on the N8101. Figure 4 below is schematic diagram of the connections required. Figure 4
Discrete components
The Simulator can be powered from the track with the addition of two readily available components: a bridge rectifier (our N301S or N302S will work just fine). If DCC operation is used, the addition of a filter capacitor (10μf or larger and minimum 16-volt) will be required. Figure 3 below is schematic diagram of the connections required.
Figure 3
This is the least expensive solution, but is has a couple of minor drawbacks. First, the bridge rectifier (and capacitor, if needed) are not mounted on a circuit board so direct solder connection is required and you will need to ensure the pins on the rectifier and leads on the capacitor (depending on the type of capacitor) are organized so that they won't short out against anything. Second, depending on the physical size of the bridge selected (and capacitor, if needed) and the scale you're modeling, hiding these additional components so they're not noticeable can be a bit of a challenge.
N8101 DC Power Source
A more elegant, but very slightly more costly ($3.95) solution would be to use our N8101 DC Power Source. It has all of the components needed, includes a circuit board with solder points, is extremely tiny (1/2 the size of our Simulator), has the lowest possible voltage loss (important for analog operators). Click here for more information on the N8101. Figure 4 below is schematic diagram of the connections required.
Figure 4
Connecting LEDs
When connecting the LED, proper polarity must be observed. LEDs are “polarity sensitive” and will not function is connected backwards. The N8032 is configured to connect to a 20 ma LED with a device voltage of 1.85-2.0 VDC. This covers all of Ngineering’s Micro and Nano yellow and red LEDs, as well as many of the yellow and red LEDs available.
Using wire appropriate for the size of the LED and its placement in the locomotive, connect the LED cathode (the – connection) to point #3 on the module and connect the LED anode (the +) to solder point #4.
If desired, a series-wired pair of LEDs can be connected in place of the single LED (see diagram of our Early-era Alternating Flasher for an example here). By doing this, this module will support 2 LED beacons (flashing simultaneously). When using a series-wired pair of LEDs, the individual intensity (brightness) of these LEDs will be slightly lower than that of a single LED connected to the same solder points.
This completes connection of the N8032 module. It is recommended that a thorough re-inspection of all connections and module placement be performed prior to applying power to the locomotive. We hope you enjoy the added realism our module provides.
So I could use the N8101 circuit to connect to the track pickup wires. In other words, since N scale locos are a split-frame mechanism. I can solder a small red wire to one side of the chassis frame, and solder a small black wire to the other chassis frame. I can then solder the the red and black wires to the track pickups to the indicated leads on Figure 4 above.