Bachmann Online Forum

Discussion Boards => Large => Topic started by: Mr. T. on February 08, 2010, 12:32:38 PM

Title: DCC decoders for Big Haulers?
Post by: Mr. T. on February 08, 2010, 12:32:38 PM
Excuse the questions of a DCC Newbie and G scale Novice.

Most DCC decoders I see out there have a maximum current capacity of 1 - 1.2 amps for motor control.

That's no doubt adequate for handling HO and smaller stuff, but is it enough to control a Big Hauler's motor?

What decoders are others using successfully for G scale locos?

Thanks!
Title: Re: DCC decoders for Big Haulers?
Post by: Nathan on February 08, 2010, 01:36:23 PM
There are several manufactures that make Large Scale decoders.

Just a quick list, by no means all:

NCE DS408 and DS808 series
MRC AD322, AD324, 0001817, 0001818, 001819
Lenz Gold Maxi
Digitrax DG383 and DG583 series
QSI

Title: Re: DCC decoders for Big Haulers?
Post by: tlnibert on February 09, 2010, 01:16:40 PM
I purchased an HO layout that has Digitrax system. What would I need so I could use it on my g scale layout?
tom
Title: Re: DCC decoders for Big Haulers?
Post by: Nathan on February 10, 2010, 01:24:24 PM
Tom,

You might go to the Digitrax web site and give the people there what model system and accessories you have.  They will be the best ones to ask.
Title: Re: DCC decoders for Big Haulers?
Post by: Mr. T. on February 13, 2010, 03:42:03 PM
Thanks for the responses!   :)

I came into a bargain on several Lenz LE 102 and LE 103 decoders...  which are now sort of useless for my purposes. I might try one of them on my 0 4 0 Porter, to see if they can handle that load without blowing.

In any case...  I also managed to get my hands on three MRC AD324 decoders which will surely handle the current of the 4 6 0 locomotives (8 amp rating).

This is my first excursion into DCC...  so I got hold of an older, discontinued system that is simple and cheaply available, but IMHO is adequate for Big Haulers; an MRC Command 2000.

To take care of the current requirements of G scale, I also got hold of the AD600 buss extender (necessary if you want to connect a booster), and I've exercised my skills as an engineer to construct a regulated, 10 amp DC supply (variable, 18 - 25 volts, based on an LM338T regulator chip and an MJ2955 pass transistor). Right now I'm debating if I should mount this beast on a 19 inch rack panel to make it look more professional (aesthetics are important), and allow for possible future consolidation and expansion of electronics.

Personally...  I'm wondering why commercially made boosters are SO damned expensive. The technology in them doesn't seem all that complex, and by scrounging, virtually all of the components can be had for next to nothing; the booster parts all came out of the "junk box" of my ham station...  cost = zero, except for a few hours to put it together!

Oh well...   looks like I'll find out about this technology.

Again, thanks for the responses.


Mr. T.
Title: Re: DCC decoders for Big Haulers?
Post by: Peter O on February 14, 2010, 09:06:26 AM
You might be able to get away with an HO decoder in the smallest o G scale locomotives if you run short trains, but why bother?

There are plenty of reasonable prices alternatives. One of my favorites is the MRC 1819 which has 5 amp capacity, a wide selection of steam effects and can be had for about $70. If you want to retain the chuff sync then I would recommend the QSI Magnum. more expensive but you get what you pay for.

Good luck

Peter.
Title: Re: DCC decoders for Big Haulers?
Post by: Jim Banner on February 14, 2010, 07:08:22 PM
Quote from: Mr. T. on February 13, 2010, 03:42:03 PM

Oh well...   looks like I'll find out about this technology.
Mr. T.


Might  I suggest that doing some reading on the subject will help you find out about this technology much quicker and more cheaply than simply trying decoders until one works?  Instead, you will be able to use your new found knowledge along with your ham radio and engineering skills to measure current requirements and predict which decoders are suitable and which are not without ever having to burn one up.  Your reading may help you understand the difference between a digital booster and a regulated dc power supply and may even help you accept why boosters are so damned expensive when you have to pay for all new components, labour, marketing, distribution and after sales service while power supplies can be so cheap if the parts and labour are free and those other costly considerations are non existant.  Reading about this technology will also help you avoid buying unnecessary items such as a bus extender for a command station with no bus.

A good starting place would be the NMRA website.

Jim
Title: Re: DCC decoders for Big Haulers?
Post by: rperego on March 07, 2010, 05:55:56 PM
I have 7 various Bachmann locos converted using NCE D13SR decoders (1.3 amps continuous, 2 amps stall) - less than $20 each.  The most draw I've measured is .7 amps pulling 4 to 5 cars, on the flat, around 5' curves.  I've also had stalls due to collisions and have yet to damage a decoder.