I don't even bother to test new decoders with the DTK. I use it after the fact. If an installed decoder seems to fail for one reason or another, I pull it out of the loco and hook it up to the DTK to see if I get any sign of life.
Rich
Alton Junction
As I said way back when - none of the 'decoder testers' actually tests anything - they hook up LEDs to the functions, and a motor and/or resistors and LEDs to the motor, and in the case of the ESU one, a speaker. You connect your DCC system to it and then operate or program the decoder. A real test device would be proprietary to each decoder manufacturer - if you look at a non-shrink wrapped decoder, you may see some small contact points (not the through holes) that aren't for soldering additional functions to - those ma be test contact points for automated testing in manufacture, or connections to program the microcontroller.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Typical NCE "manual". All of 4 pages, and the first and last pages don't even contain any operational information.
After I bought mine years ago, I wound up on the NCE-DCC forum (Yahoo Groups) asking for help on how to use it. Then, I made a bunch of notes for myself which are more helpful than the manual.
The DTK is a fairly crude device, and it predates sound decoders so there is no way to test sound.
Hi Jim N:
Welcome to the forums!
You can find the Decoder Test Kit pdf on this page. Scroll down to 'DTK Drawing pdf' about 1/2 way down the page and to 'dtkman.pdf' about 2/3rds the way down.
https://ncedcc.zendesk.com/hc/en-us/articles/201565479-Mobile-Decoder-Manuals
To be honest, I have discovered the same thing as Randy - a Decoder tester is a waste of time. I went to the trouble of attaching the DTK to a board and connected an actual motor and speaker as well as buying all the leads needed. I used it once and I haven't touched it since, and I have installed a bunch of decoders since I bought the DTK.
Having said that, if you are planning on buying older MRC decoders that are prone to failure, using the tester might save you some headaches. For several years I have only bought ESU Loksound decoders (usually Selects) and I have never had a problem. If any of my older Soundtraxx, QSI or other decoders cause problems they will simply get replaced with Loksound Selects. It is definately worth sticking to one brand of decoder to reduce the amount of head scratching you have to do to remember which locomotive does what with which function button.
Dave
EDIT:
maxman beat me to the post of the links while I was babbling on about my opinion of decoder testers.
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
jnsdI have inherited an NCE decoder tester with no paper work. The pdf is no longer on their web site, at least I can't find it. Is there a possibility of your sending me the pdf file?
I found the instructions on the NCE site. Open this link: https://ncedcc.zendesk.com/hc/en-us/articles/200935515-Decoder-Test-Kit
You'll see a spot down toward the bottom left where it says dtkman.pdf Click there and the manual will appear.
I have inherited an NCE decoder tester with no paper work. The pdf is no longer on their web site, at least I can't find it. Is there a possibility of your sending me the pdf file?
Thanks,
Jim N
filmsnotdead at gmail dot com
Randy:
I think you hit the nail on the head when you describe what a 'true' decoder tester would do. I guess I was being naïve when I bought the NCE DTK. I was expecting a bit more.
Thanks as always for your input everyone.
Thing is, there's not much to one. I just read the instruction sheet, not sure what additional questions there would be? It shows you how to hook up a decoder, then tells you to operate it as normal - which is exactly all there is to it. There's an LED for F0F and F0R, and for F1-F4, plus the big light bulb that acts as a motor load - or you can connect a motor. Two wires to the track, and then there's an 8 pin connector and a 9 pin connector for various types of decoders.
Obviously needs clip leads (which they mention) for board repalcement type decoders than have neither an 8 pin or 9 pin connections. About the only thing the left out that would be handy is a full pinpout of the 9 pin and 8 pin connectors and the proper NMRA color code for them.
The big secret is that a decoder 'tester' doesn't actually 'test' anything, it just acts like a loco so you can run the decoder from your bench with nothing having to move anywhere. A true 'decoder tester' would be a device you attach the decoder to, and it would run through some basic programming, run the decoder forward and reverse, and activate each function, and then report pass or fail, or indicate what parts are working and which aren't. Perhaps load a speed table and veirfy both readback AND that it changes the output on the motor wires. Such a device is entirely possible to build, but would cost a LOT more than $24.95! I remember we used to have an IC tester that cost several thousand dollars, but you could plug in darn near anything from 8 pins up to 40 pins, and it would figure out what type of chip it was, (AND gate, OR gate, NAND, etc) and what family (TTLE, CMOS, LS-TTL, etc) and test it accordingly. Pretty darn neat, but for a home user - you'd have to buy a lot of (at the time) 75 cent (common TTL 14 and 16 pin) chips to make up the cost of that tester. I don't doubt the decoder makers have test equipment like that that can validate a decoder without having to use a throttle and issue commands.
I think my DTK might be headed in the same direction. I think all it does is point out the obvious.
Oh well, lesson learned! What did P.T. Barnum say? Something to the effect that "there is a fool born every minute".
OH, that's nasty! However, if NCE thought the DTK was worth the time, you would think that they would properly support it on their website with much more information.
ESU has one that has multiple types of connections, an actual motor, and also a speaker to test sound decoders.
I don;t have one yet. Not sure if I ever will. One fo the first things I built for myself after going DCC was a decoder tester, similar to the old Loy's Toys one. I used it once, to verify it worked. It's been buried in a drawer ever since. I've gone through a lot of decoers, and have yet to have one bad out of the package, and since I always test on a low current program track before putting the loco on the full power main, I have yet to smoke one.
Sounde decoders, especially since I decided to standardize on ESU, may be different, since I need to load sounds in them. But even so, using the subminiature clip leads, I can easily and quickly attach a speaker and connect the decoder to my program track that has the Lokprogrammer connected to load sounds, and you cna run through a test with it as well, even without a motor connected, to hear the sounds. I have a feeling that if I did buy the decoder tester, I would use it once or twice and it too would end up in the bottom of a drawer, unused.
Somebody on the NCE-DCC forum once told me that he had abandoned the DTK in favor of simply installing the decoder in the loco and testing it that way.
Aside from testing the higher functions, the DTK is a fairly crude device that I find mainly useful to confirm that the decoder is receiving power and transferring it to the motor, and that the function outputs that control the lights are working.
There must be a better decoder testing device out there.
Rich:
I guess if all the tester does is show that the decoder is supplying power to the various outputs then I have figured it out. Martin's method of testing functions higher than F2 is very useful.
Part of what threw me off was that my Power Cab needed to be reset, and I was trying to use the tester before I realized the reset was needed. When I first posted I hadn't figured out that the reset was needed so of course I couldn't get the tester to work, hence my confusion. Many of you will know already that I am easily confused!
I looked at the PDF and it shows me everything about the tester.
Knowing how decoders are used helped a lot.
I have used the grabbers as I started using the grabbers many years ago with the old style wire wrap electronic circuits.
I also keep a set of double clip leads from Harbor Freight.
http://www.ncedcc.com/images/stories/manuals/dtkman.pdf
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
That's exactly what I have.
Here is an eBay listing for the same clips. Note that you will need two sets to make up the cables and they do not come with any wire:
http://www.ebay.ca/itm/F01893-8-colors-SMD-IC-Single-Hook-Clip-Grabbers-Test-Probe-cable-for-multimeter-/261145238846?pt=Home_Automation_Kits&hash=item3ccd781d3e
Here is the wire I used. You won't need that much for the jumper cables but having a selection of coloured multi-strand wire on hand is not a bad idea:
http://www.ebay.ca/itm/10-ROLLS-1-0-AMP-STRANDED-EQUIPMENT-WIRE-100-mtr-DX1210-/390670376521?pt=Model_RR_Trains&hash=item5af5c4de49
Note that these are Canadian eBay listings but I'm sure those of you south of the border will be able to find the same thing.
I take it you mean something with ends like these:
Those are PERFECT for decoder testing - the clips are small enough to attach around the wires from a wired decoder, and big enough to clip through the holes usually present on board-style decoders. Only a little conductor is exposed at the tip, so they are fairly safe from shorting.
Dave, that was a good move purchasing that set of jumpers with the small spring loaded 'J' hooks. The fact that they are color coded so that they match the decoder wire colors does, indeed, make things easier. And, I agree, that they are insulated to offer maximum protection against shorts.
Martin:
Thanks for explaining how to test functions above F2.
I haven't gotten around to mounting it on a board yet but I will do so. That allows a speaker to be mounted so a sound decoder can be tested, and gives the option of mounting a motor instead of just using the light bulb supplied. Tony's Train Exchange has an article on how to upgrade the tester.
I have a set of jumpers with the small spring loaded 'J' hooks. There is very little exposed to allow for a short but care is still needed. They are colour coded so they match most of the decoder wire colours which makes things easier.
I will explore the NCE-DCC forum.
One thing I have discovered is that there are labels on the circuit board that identify the various inputs and outputs. However they are so faint that they are practically impossible to read. I didn't realize they were there until I was looking at the picture of the board on the front of the manual where the labels are at least somewhat visible.
I mounted mine on a board. Track is connected to the track connections on my booster. Since I'm N Scale and will probably never see a decoder that uses the 9 pin plug, I connected its leads to a barrier strip and plugged the other end into the tester. Wire color on the harness matches those of a decoder. Now I just connect the leads of a wired decoder to the terminal strip and test away. For test functions above F2, I disconnect the wire from F1 on the terminal strip and connect the function wire I want to test in its place. I use F1 because it is latching on my Digitrax system. F2 could also be used.
That's for testing. For programming<, I can leave it connected to full track power and program on the main or I can connect the two track leads to my programming terminals.
Martin Myers
Critter, my only comment is that I absolutely agree with you on the utter lack of any detailed instructions on how to use the DTK.
After I purchased this unit several years ago, I spent several hours back and forth on the NCE-DCC forum on the Yahoo web site getting help and advice on how to use it.
A few words of advice. Mount the DTK on a small board to make it easier to work with. Out of the box, it is nothing more than a circuit board with a whole bunch of loose hanging wires. And, head over to Radio Shack and buy some insulated alligator wire clips. I have damaged a couple of decoders testing things like light functions when exposed alligator clips shorted the decoder terminals by touching one another.
I have purchased an NCE Decoder Test Kit. Unfortunately it comes with absolutely lousy instructions. There is no explanation of what responses the decoder test kit should have to various inputs.
Can anyone connect me to a detailed explanation of what the tester should do when the decoder is working properly, and perhaps more importantly, what indications will it give if the decoder is defective?
Thanks
P.S. The NCE web site offers nothing more than a PDF of the manual that came with the unit. Tony's offers enhancement suggestions but not the information I am looking for.
EDIT: I just found out why I couldn't get any response from the DKT. I needed to reset my NCE Power Cab. Once that was done the responses from the DTK were fairly easy to interpret.
This is the second time I have had to reset the Power cab. It has only happened since I installed version 1.65 of the software a few months ago. Any comments?