Review of MRC's #1907 DCC decoder with sound for the Atlas S2/4
By Mark J. Redmond with Jay Scott
May 24, 2012
Well, my attempts to do some overhauling of my Atlas S2, putting in a new motor, resulted in me putting the motor in upside down (YES you can do that) and I shorted my old #1607 MRC decoder and ruined it. This actually turned out to be a good thing because since I did my last review of the 1663 decoder, MRC came out with their 16 bit version #1907 and WOW they hit the mark.
Installation
I am again going to refer you to Jay Scott's review of the old MRC #1663 which was excellent in helping with installation. Click here for Scott's page. His review made an easy installation even easier. It took me about an hour to complete the installation. (Since I already did the modifications, it took me less than 30 minutes to install it this time.) You will have to do some milling of the top weight but it is very easy. One thing to take note of is MRC does not give you everything you need for the decoder installation. (This has not changed.) You will need to find some Kapton tape and a 2-56 nylon screw so you can insulate the motor. You will need a fair amount of Kapton Tape as you have to tape almost all of the upper weight. I strongly recommend Kapton tape over electrical tape. Kapton tape is very thin and leaves no sticky clue residue when removed. I happened to have these items at work but any large electronic warehouse type store should carry these items. Radio Shack does not carry these items.
One item I did do differently and recommend is to use electrical tape of black shrink tubing to cover all but the end of the rear LED. This makes the rear light more realistic.
Here is a picture of the rear LED covered in electrical tape. Note I did not yet crimp the bad end which you need to do. The excess in the front acts as a light pipe keeping the light beam focused.
Like the #1663, the #1907 MRC decoder only makes a click so you know it has power. The locomotive does not turn the sound on until you select it.
Operation
Yes, MRC DOES indeed listen to its customers. Many of the issues I had with the #1663 decoder were GONE! When you start up the locomotive the very first thing you notice is you do not need ear plugs. Note, if the locomotive is the locomotive you last used, you may get locomotive sounds on system power up. Although the factory default for volume is at the highest, it is noticably quieter than the #1663.
Other changes I noted were;
You now have a choice of two prime mover sounds and they are closer to the real locomotive now.
You have a master volume control. No more having to adjust every sound.
You have 22 horn sounds (17 on the 1663) and 8 bell sounds (7 on the 1663)
The horn still works better than my Tsunami decoder. Pressing the horn button on and off, you get the exact time. No delayed off or fixed minimum time. Just like a real locomotive.
The decoder now comes with the adjustable back EMF closed loop speed control. (momentum) I asked MRC about this and they replied, "There is factory momentum programmed in to protect the decoder and gear train from abrupt direct movements. So this cannot really be turned off, unless you play with the adjustable back EMF, (not recommended). Make sure CV's 3 and 4 are zeroed out. While I am not crazy about it, I listened to them. I have gotten used to it. One nice thing about it is when you are switching and need to change direction, just press the direction button, the locomotive slows, stops and goes the other way in one motion.
I have done a video and you can check it out on YouTube here.
Consisting
As I am not planning to do any consisting please see my findings from the #1663 review. MRC also provided me with a PDF file on how to program your MRC decoder for consisting on the main. Click here for the PDF.
Conclusion
Pros
Price - A very inexpensive way to get started in DCC using some of your older locomotives.
Installation - Very easy.
Customer service - Top of the chart. Quick informative responses and most importantly they listen to their customers!
Cons
Kit not complete - Still did not add the Kapton tape and nylon screw! Add a couple bucks to the price. It's worth it to make your easy install even easier.
I have to say that frying my old #1663 turned out to be a blessing. This new decoder is worlds apart better than the #1663. The #1907 should now be considered a 'buy it' rather than the 1663's 'no other choice'. I am very pleased with the changes and if you have an older locomotive and want to get DCC, check out MRC. The cost is low so if you do make an error you do not lose a lot of money.
