Installing wired decoders in latest Kato Shinkansen models

[Costas]

Hi everyone,

 

I'm considering purchasing some of the latter Kato Shinkansens eg: N700A, E6 etc and was curious as to how easy is it to fit non Kato DCC decoders [hardwired ie not PnP] into these models.

 

I am very comfortable installing [and have already done so] wired decoders into their erlier models such as their series 100, 500, 800 and early 700 series Shinkansens.

 

Due to the latter models being designed to specifically accept the appropriate Kato decoder - is it still feasible to disassemble the model and install a wired decoder in the model. What I am specifically looking for is an answer in regards to whether it is reasonably easy to still access [and isolate] the motor connections and still also have access to the main Copper strips providing power from the bogies.

 

I have quite a few small Digitrax decoders lying around looking for a home.

Edited January 24, 2014 by Costas

[Martijn Meerts]

In most cases it's actually easier to install wired decoders in the DCC-Friendly Kato trains. You can (in most cases) use the pocket meant for the Kato decoder to any other (small) decoder. Instead of sliding the Kato decoder in place, you can just grab a bit of styrene, cut it to shape, and fit that instead of a Kato decoder to isolate the motor. You can still isolate the motor the normal way too of course. The wires can be soldered as you would normally do.

 

I haven't installed a decoder into any of the newer Kato shinkansen, but I have done a wire install in their 151 series train, which is also a DCC friendly one, and it was no problem at all.

[Vato]

I have installed wired decoder in kato sunrise express old model, not a dcc friendly with no problem and it's work fine

[westfalen]

I've hardwired a decoder in my Marunouchi Line subway train because although it is set up for an EM13 and the catalog says so, the mechanism leaves no room for the docoder to fit. Hardwiring was easy enough and the FL12 still fits the end cars.

[Costas]

OK - Thanks, Looks like it should not be an issue.

[E6系]

Hello Mr Costas,

 

Could you please tell me why you do not wish to use the Kato decoders? 

 

You comment that you have some Digitrax decoders available.  The Kato decoder is actually made by Digitrax.  It even includes transponding.  My suggestion is to use your existing decoders on other models and purchase the purpose made decoders.

[Ochanomizu]

Hi Costas,

 

I swap Kato decoders between models.  Thus, I only need 6 sets of Kato decoders, even if I own more consists.  I think this is an economical solution.

[Costas]

I had given some thought to purchasing specific Kato decoders [much simpler to fit] for the models but it would seem wasteful in not utilising the relatively large number of spare decoders that I already have lying ariund.

 

I normally pull all my cars apart in that I usually modify the Head and Tail lights [brightness and colour] by replacing the OEM LEDs. I also fit my own design flicker free interior lighting kits to all the cars by utilising LED strips. Therefore while the cars are each disassembled - it usually presents no problem for me to also fit a small decoder in the requisite model - even if it requires hard wiring as my background is in electronics.

[cteno4]

Costas

 

Curious what your interior lighting design is.

 

Thanks

 

Jeff

[Costas]

Hello Jeff,

 

I purchase LED strips which work out as a relatively cheap interior lighting option. The strips come in many variants [LED sizes and colours] and in my case I purchase ones which have either COLD or WARM LEDs fitted. The warm led strips I use on my earlier trains and the cold white led strips on my more modern fleet to obtain my preferred look.

 

You can usually buy the led strips in sections of metres which can be cut to length. The only thing to be aware of is that I purchase strips which are designed to operate off 12v. The strips use very high efficiency LEDs and for 12v operation they normally wire three LEDs in series and power them via one resistor. You can cut the strips every 3 LEDs along and no shorter as the three LEDs must remain as one circuit. In the photo below you can see that a three LED section is 50mm long - So the minimum length we can use is 50mm.

 

This works out quite well as I normally utilise a 100mm length of LED strip [6 LEDs - as pictured below] for my end cars in Shinkansens and 150mm [9 LEDs] sections for all the other cars - They fit pretty much spot on. I have also used them in some of my US prototype diesel trains and they typically house a 150mm length as well.

 

The LEDs are extremely bright if run directly as they come supplied so I change the resistor that is fitted to every three led section with a much higher value. Typically the resistor value fitted as supplied is around 100 Ohms and I swap this out for either a 2.2K Ohm or even a 4.7K Ohm resistor to drop the brightness substantially.

 

There are two major benefits which occur when the resistor is changed to much higher value. First is the drop in brightness to a much more realistic value and second is the fact that the LEDs draw extremely low current with the higher value resistor [only 1 or 2mA per car] - This allows me to use a very simple yet very effective anti-flicker setup in each car.

 

Note that the LED strip has a stick on backing and it is simply a matter of peeling off the protective backing paper so you can stick the LED strip directly onto the interior of the rooftop within each car.

 

 

 

 

As most of us know, interior light flickering can be an issue yet it can be elliminated with two simple components when utilising the modified LED strips as I have mentioned above. Since they draw very little current, only a relatively low value capacitor is required to keep the voltage up to the LEDs when traversing a poor conducting spot on the track.

 

With my testing - I have found a that a SMD tanatlum capacitor of 100uF is adequate for the task and it will elliminate flicker caused by poor/dirty track pickup quite well. The only other component required is a small bridge rectifier which rectifies the incomming DCC square wave and allows us to connect the capacitor to DC rather than an AC waveform which would not be good...! I normally hide these two components under the floor pan in the majority of Shinkansen models - In some cases you can also easily mount these components in the main seating area of cars and you can usually hide them somewhere so they are not visible through any windows.

 

If there is enough interest, I can probably post a simple build thread on a typical Shinkansen car etc.

Edited January 30, 2014 by Costas

[E6系]

Hello Mr Costas,

 

Yes please, I would like to see a step-by-step conversion of your shinkansen car.

[Martijn Meerts]

Costas, sounds interesting.. The flickering interior lighting is on of the things that annoys me the most on a layout. Even with perfectly clean tracks and wheels, there's no getting rid of it just using the regular interior lighting kits ...

[kvp]

there's no getting rid of it just using the regular interior lighting kits 

If you are using conventional DC, then you just have to add a large enough bipolar (AC) capacitor parallely to the light board. Some manufacturers even put the mounting pads for it on the board. If you are usind DCC then adding the a rectifier bridge seriallly between the light kit and the pickups and any kind of large enough capacitor parallely to the kit after the rectifier will solve the problem. This will work better with low current leds, since the less the power consumption, the smaller the capacitor. The 3 led solution above works only with 12V DCC or PWM based DC controllers, but cutting the led circuit into 1 led pieces by disconnecting the middle stip and adding a resistor to each one (between the botton strip and the middle trace that remained with the led) would lower the turn on voltage to around 3.2V (+-0.2V). Since only the middle trace has to be cut, the whole strip could still be glued to the roof in one piece. If you are lazy to cut small sections out, just punch small holes with the right tool that brakes only the middle trace. Important to never use them on full power, since the heat from the resistors would melt the top of the coaches.

 

ps: I just happen to know a few things about these because last year i installed a few of these strips in the kitchen above the sinks on the bottom of the cupboard and checked the driver circuit and it's a 240V to 12V transformator, a rectifier bridge and a large cap to prevent flicker. With only 3 leds, the driver circuit that was designed for 2 meters would light them for many seconds after the power is turned off (and they turn off below 9.6V). With 2 meters the turn off is very fast, around 1 second.

[Costas]

The best way I found to elliminate flickering with a single standard LED and the Kato lighting kits is to first drop the incomming voltage [typ 12v for N scale] via a small 5v regulator and then power the LED via a resistor and suitable capacitor.

 

I have used this method in the past on a few of my models and it works very well - However I found that a reasonably sized capacitor is required to keep the flicker at bay mainly because the majority of single LED lighting setups use a standard LED which requires 20 or 30mA for full brightness. Due to the relatively high current being drawn, a physically small low value capacitor does not always work too well in keeping the LED powered during intermittent breaks in power. I found that values of 330uF or higher were required for optimum results which means either a single larger capacitor or multiple smaller capacitors [surface mount] need to be used - This can be a challenge in some installations due to space/size restrictions.

 

I have now moved over from utilising the Kato lighting kits and over to the LED light strips due to their very cheap cost. You can buy these LED strips on Ebay and many other places quite cheaply {i purchase mine from a local electronics shop]. The advanatge they offer is that they draw extremely low current [once resistors are changed to dim the LEDs] per car and a typical passenger car is fitted with 9 LEDs across the roof which reults in fairly even lighting of the interior. Being a very low current setup - It only requires two small additional components to make it a flicker free setup.

[Costas]

Here are a couple of quick comparisons of the interior lighting.

 

Left hand Shinkansen car is an 800 series fitted with LED strip [9x LEDs] and the one on the right is a 500 series.fitted with a Kato lighting kit [single high brightness LED].

 

It is difficult to capture the lighting differneces in a quick photo but i did I think these two photos show the differences the best.

 

If you look carefully you can see that the 500 series KATO equipped car on the right becomes brighter as we move from the left to right - This is due to the single LED arrangement of the KATO lighting kits and in this case the LED is mounted on the right side of the car. The 800 series car has much more even lighting spread due to the 9 LEDs which are fitted along the roof line.

 

 

First photo with no ambient lighting:

 

 

 

 

Second photo taken with a small amount of incandescent ambient lighting off to the side with camera viewpoint shifted slightly higher for a slight top down view of both cars.