terminate bus ends for DCC

[cmrproducts]

Digitrax has never stated in any of it’s manuals about terminating the track Buss nor the Loconet that I have read. It was on the NCE forum that I read about this problem with their system and began to investigate the reasoning behind it.

It seems that Digitrax’s system is somewhat different in this respect than others especially with the Loconet.

Now as I stated above I ran into the problem and this is only on the Track Buss that this noise is causing problems.

Remember that the terminator is just an RC filter and it is passing the high frequencies (noise) to ground (for lack of a better term – I really do not want to get into a bunch of electrical theory here). But it worked in my situation. Your mileage may very.

As far as my Loconet, it is working fine as I use Radio almost exclusively and it is working great in all of the other sections of the layout. It was just these two areas that were the furtherest from the power boosters (of which I have 3) that gave the problem.

BOB H – Clarion, PA

[NZRMac]

QUOTE: Originally posted by MisterBeasley

My Lenz system came with resistor, and instruction on where to put it to terminate the bus. I did as I was told. Before I did it, though, I tried the system out and it did not behave itself. That bus was only about 20 feet long, but it did make a difference.

So, consult your manual, and do as it suggests.

Is that what the resistor was for?

I just re-read my Set 100 instructions, the resistor I got with the set is for putting in series with the programme track. Does your instructions say different?

Thanks, Ken.

[MisterBeasley]

My Lenz system came with resistor, and instruction on where to put it to terminate the bus. I did as I was told. Before I did it, though, I tried the system out and it did not behave itself. That bus was only about 20 feet long, but it did make a difference.

So, consult your manual, and do as it suggests.

[cmrproducts]

There is no need to terminate the Buss wires usually, until they reach over 50 feet in length.

I finally ran into the probleThere is no need to terminate the Buss wires until they reach over 50 feet in length.

I finally ran into the problem on my layout. And the only way I really understood what was happening was I could no longer control certain engines at the far ends of the layout. They would unexplainably lose control. At first I thought that it was the Radio signal loss that was causing the problem but when I plugged the keypad into the layout I still could not control the engines. So I just changed out the engines and then some worked while others still would not run right.

After the OPs session I made Buss terminators and tested the layout and trains at the same spot that I had trouble during the OPs session I had and the same engines were acting up. This time though I was the only one running a train so this eliminated any interference from other trains on the layout.

I added the terminator to the end of the Buss wire in the problem area and then tried the engines again. Suddenly they were back under full control. They responded to any changes in the speed and directions that they were given.

So I then put another terminator at the other end of the layout which was also having the same problems and the OPs session we had last night (Thursday) there were no reports of run away trains.

So I must have gotten the problem under control.

BOB H – Clarion, PA

[martin990099]

thanks guys[8D]

[simon1966]

Nothing special at all. Wrap them round a nail, just to keep them neat. Make sure they are insulated so they can not short together.

[NZRMac]

You really don't need to terminate the power bus. Just insulate the ends and it's done. Don't loop the throttle bus either if you have one.

Ken.

[martin990099]

I have a 3x6 layout and am making bus wires in an "U" shape, and was reading the other day to terminate them for DCC. My bus wires are about 12' and I am using a Digitrax Zephyr.

So can anyone tell me what that is and how to terminate the bus wires on my layout. [%-)]

Pictures would be really helpful.[:D]