# MRC Decoder for KATO Problem?



## Texas Hi-Railer (Jan 28, 2015)

Howdy All, I'm new to this forum & I've looked around for this subject & didn't find it so, please excuse me if this is a repeat thread? I purchased an MRC #1802 Sound Decoder for my KATO SD40-2 BNSF locomotive that I received for Christmas which was DCC equipped but did not have sound. 

Being very new to DCC after 30+ years of DC operation, I finally decided to try DCC after fighting it for a few years simply because I'm an "old school" kind of guy & I don't do well with modern day technology. In fact, I had to take a community college class several years back before I purchased my first computer simply because technology frightens me, lol. I made the decision to go with MRC simply because they are much cheaper than other DCC decoders plus, I'm still not sure of myself with this DCC & didn't want to spend a lot of money if I don't like it?

Anyway, I purchased the MRC #1802 decoder for my KATO locomotive & the sound is amazing, no complaints there of any kind. I am very, very impressed with this whole sound idea & I am getting use to DCC operations however, the lights on this decoder are very dim & difficult to see in the daytime. The factory decoder from KATO had beautiful bright lights before I replaced the decoder with this MRC & in fact, I re-installed the KATO decoder to see if perhaps I did something wrong & all was well, bright lights & all. I re-installed the MRC decoder once again & am right back to dim lights again?

I checked on a few other forums & noticed this was the #1 complaint with this particular decoder but, nobody mentioned how to correct the problem? Is anyone familiar with this issue & is there a fix for this problem? At first I thought perhaps I purchased a bad decoder until I saw this issue on other forums. Can anyone assist me with this issue? Thanks in advance & I look forward to being part of this forum... it came highly recommended.


----------



## CTValleyRR (Jul 26, 2014)

Well, I'm not really good with all this electronics stuff either, but hopefully one of the real smart guys on here will jump in and help. Meanwhile, my limited knowledge would suggest thst the MRC decoder is providing less voltage to the lights than the factory one. You should be able to verify this in the manuals for the two decoders.

So if I'm right how do you fix it? Short of swapping out the bulbs / LED's for lower voltage ones, I have no idea, unless there is a CV (configuration variable -- basically a short programming setting) on the decoder to change the voltage output on the lighting.


----------



## Texas Hi-Railer (Jan 28, 2015)

Howdy & thanks for the quick response. The one thing I noticed right out of the gate is, with the factory KATO decoder the lights are bright white in appearance where with the MRC decoder the lights are a yellowish, almost an amber look to them? They appear to be just as bright voltage-wise however, when you place the shell back on the chassis the lights are barely glowing. At night they are there but, they look like they are in the dim mode or even maybe lower than that?

I've looked at both the manuals, the one that came with the KATO loco which doesn't say much about the decoder & the MRC says very little when it comes to lighting. It talks about the ditch lights & how to program those to flash but, nothing about making the lights brighter, at least not in the manual? I was hoping someone might know a trick to this decoder or might know how to program it so the lights are brighter.

The lights look like little diodes, or whatever you call them on the decoder circuit board & are not actually bulbs as we know little candescent bulbs like we're use to???


----------



## CTValleyRR (Jul 26, 2014)

Now you're really getting out of my comfort zone. Maybe a whiz kid will jump in here. 

The little diodes, as you call them, are LED's. You change the color of them either by putting a colored lens on them or by using a different color LED. Just changing the voltage doesn't change the color. That said, an LED is generally designed for a specific voltage, and you generally add a resistor to step the input voltage down to the required level. If your input voltage changes, the amount coming out of the resistor does, too, and your LED isn't getting the voltage to operate correctly.

The right answer is to change out the resistor. And that pretty much finishes my ability to help.

Looking back, are you saying that the LED's are actually on the decoder?


----------



## DonR (Oct 18, 2012)

Most DCC and Sound decoders light terminals provide 12 V DC.

You might see if that is what is going to your lights. If it is,
there must be some resistance in your original light circuit.

A lower voltage does dim LEDs and sometimes results
in a somewhat yellowish glow. That is apparently what
you are seeing.

Don


----------



## wvgca (Jan 21, 2013)

I looked at the mrc pdf on that decoder, and it does mention a 'dim/bright/off' cycle available on the lights .. cv117=1 ... for normal [maximum brightness] cv117 should be set to 0 ... on another forum a user mentioned that the lights on the new mrc board are not properly aligned with the light tubes in the shell, however I find that unlikely as the new pcb fits into the same mount tabs as the old one ....it may just be that the mounted led /on board smd resistor used on that pcb may not be putting out the same brightness as the stock board .. and that is fixable, but not easily .. as leds and drop resistors are mounted directly on that pcb, I have changed the smd mount leds and dropping resistor mounted on HO scale 'drop in' decoder boards, but I'm not sure if my eyes [even with magnifier lenses] are good enough to do that on N scale pcb's ... you may just be stuck with dim lights ...


----------



## Brakeman Jake (Mar 8, 2009)

Fix is easy...get a good decoder.MRC sell cheap...that's what they are.


----------



## D&J Railroad (Oct 4, 2013)

Brakeman Jake said:


> Fix is easy...get a good decoder.MRC sell cheap...that's what they are.


Ya get what ya pay for. The TCS WoW decoder is one spectacular sound decoder. If ya think the MRC was good, you will be blown away with the TCS.


----------



## Fire21 (Mar 9, 2014)

I saw the same thing with my Kato N-scale PA-1 and an MRC sound decoder. I was told by one of our members here shortly after I joined up that the yellow LEDs are cheaper than white ones, so that's why they use the yellows. I have not yet replaced my yellow with white, so cannot speak whether it's a cure or not.


----------



## DonR (Oct 18, 2012)

Looks like WVGCA has nailed it.'

Set CV 117=0 for maximum brightness.

Don


----------



## Texas Hi-Railer (Jan 28, 2015)

Yeah, I located that info as well & was able with my limited knowledge to set the CV so the lights dim/on/off but I couldn't find anything on making the lights brighter? I'm not real good with understanding all of this new technology which was my biggest fear in going with DCC in the first place. When it comes to modern technology with computers & electronics, I don't mind saying I'm dumb as a rock!


----------



## Texas Hi-Railer (Jan 28, 2015)

Brakeman Jake said:


> Fix is easy...get a good decoder.MRC sell cheap...that's what they are.


Well, that's what I'm thinking myself. I called MRC tech people & they were no help at all basically. They told me to send the decoder back to them & they would replace it free so, that's exactly what I did & I have the same problem? I'm thinking it's a cheap decoder as you say & I learned from my mistake.

Like I said in the original post, I simply bought the MRC because it was much cheaper & I was new to DCC at the time & didn't want to spend a lot of dough if I wasn't going to be happy with this operation. What I've recently done was simply install the original pcb back into the locomotive without sound until I can get a better decoder. Living on a very limited budget I don't have the luxury of buying expensive toys which was another reason I've been avoiding DCC all this time.

I have three other locomotives that came with factory DCC & Sound and I love those! I'll look into this TCS decoder to see what that's all about. My problem again is understanding this stuff & when looking over all these different decoders out there... I have absolutely NO idea what I'm doing, plain & simple! LOL

I appreciate all the input guys, really.


----------



## Texas Hi-Railer (Jan 28, 2015)

wvgca said:


> I looked at the mrc pdf on that decoder, and it does mention a 'dim/bright/off' cycle available on the lights .. cv117=1 ... for normal [maximum brightness] cv117 should be set to 0 ... on another forum a user mentioned that the lights on the new mrc board are not properly aligned with the light tubes in the shell, however I find that unlikely as the new pcb fits into the same mount tabs as the old one ....it may just be that the mounted led /on board smd resistor used on that pcb may not be putting out the same brightness as the stock board .. and that is fixable, but not easily .. as leds and drop resistors are mounted directly on that pcb, I have changed the smd mount leds and dropping resistor mounted on HO scale 'drop in' decoder boards, but I'm not sure if my eyes [even with magnifier lenses] are good enough to do that on N scale pcb's ... you may just be stuck with dim lights ...


Warren, are you telling me I need to set CV 117 to "0" value to brighten the lights? Am I understanding that correctly above where you say CV 117 = 1 is "normal brightness" or is that "Normal operation" as in no dim/bright/off? Thanks pard, Bo.


----------



## wvgca (Jan 21, 2013)

cv117 set to zero [0], will give maximum brightness , two steps [on or off] ... set to 1 will give dim / bright / off when you push the function button for lights .... three steps, , and set cv117=2 for rule 17 lights, maximum brightness in direction of travel, dimmer on opposite end.. unfortunately from what I can tell, these come from the factory pretty dim ... and a yellow tinge .. which is supposed to be more 'prototypical' ... in general yellow / warm white / daylight leds are a little more money than standard 'bright white' , real low cost leds will have a 'blueish' tingle, ... on my layout the era is 1890, and lights were generally oil burners, so I buy cheap 3mm flat face bright white leds, run 5k to 8k resistors so they are fairly dim, I don't want leds to light up 10 feet of track in front, and I also coat them in Tamiya clear yellow translucent paint to get a closer appearance to 125 year old loco lights... personal preference


----------



## Texas Hi-Railer (Jan 28, 2015)

Well it must be the LEDs on this MRC decoder because this is my 2nd decoder (factory sent me a new one free) & I have the same dim, yellowish lights. I had thought about perhaps the LEDs weren't lining up like someone had mentioned on this thread but that doesn't seem to be the problem? I even attempted to buy new plastic lenses in a kit made by KATO for this specific locomotive but, they are completely sold out & I got an email back from KATO saying they have no plans to restock those parts at this time? Why do these guys build & sell these things, then only sell a limited supply of parts? I hate that of many companies. They never think people need more parts???

Well, either I'm going to have to just spend more dough to buy a better decoder or simply put up with what I have, which I am not happy with at all. I just expected more for my $75 but I guess that was asking too much? Now I have to figure out which company makes a decoder for this particular model? I've tried twice now typing in a sound decoder for the KATO SD40-2 locomotive & it keeps showing MRC's decoder like that is the only company making them for after-market decoders? I asked KATO about it & they claim they don't make a sound decoder for that locomotive. If I had known that at the time I purchased the locomotive, I would have bought something else!

Thanks my friend, I truly appreciate it pard.


----------



## Brakeman Jake (Mar 8, 2009)

I sure wish it keeps up for you...MRC decoders have a pretty high failure rate so might upgrade sooner than you'd wish.Sorry to say this...

What's your Kato loco stock number?Soundtraxx likely makes a decoder for it....


----------



## Texas Hi-Railer (Jan 28, 2015)

Brakeman Jake said:


> I sure wish it keeps up for you...MRC decoders have a pretty high failure rate so might upgrade sooner than you'd wish.Sorry to say this...
> 
> What's your Kato loco stock number?Soundtraxx likely makes a decoder for it....


You're right on target there Jake as I just located a decoder from that very company for my KATO mid-production SD40-2 loco. After briefly communicating with the tech dept. there, they suggested the decoder I want for that specific locomotive is the SoundTraxx TSU-KT1000 decoder.

I've decided I'm just going to pull the MRC decoder & go ahead with the SoundTraxx decoder. As the old saying goes, "you get what you pay for" so, no more cheap MRC decoders for this oldman, lol. Thanks a bunch guys, I really do appreciate all the input.


----------

