Bachman DCC Decoder Installation

[buzzard975]

I'd like to install a decoder in an older Athearn Pa-1, but I don't have a programmer.  If I install the "Bachmann�44913 EZ Command Decoder/Harness", can I program it with just my  Bachmann EZ command controller?   Here is a link to a place that sells them.

http://www.modeltrainstuff.com/Bachmann_DCC_Decoders_s/2209.htm

Thanks

[Yampa Bob]

Hi Buzz
The Bachmann 44913 decoder is fully compatible with the EZ Command controller, so the simplest answer is; if you can correctly install the decoder in your locomotive, your EZ Command will control the decoder within the limits of EZ Command's programming capabilities.

Please refer to the EZ Command FAQ for more information.

http://www.bachmanntrains.com/home-usa/ezcommand.php?ezpage=4

Regards 

[buzzard975]

Thanks for the quick response! I'm new to the hobby, but I am pretty good with a soldering iron and know some electronics basics.  The trick with the Athearns is the frame is part of the circuit so you have to isolate the motor from the frame if you install an encoder.  Should be an easy install.

One more question about the Bachmann decoder, if I get more involved in the hobby (which is looking likely as it has been a great stress reliever!), and if I buy an NMRA compliant programmer, will I be able to change the CVs on this decoder?  At some point I'd like to run my Athearns in consist with my Bachmanns, but I have a feeling that at the same speed step they will be running at different speeds.  I'm guessing you shouldn't put trains in consist if they are not matched as far as speed.   If I can change the various CVs with a programmer I would be able to get the speeds to match a little better, right?

Thanks!

[SteamGene]

I don't know if JMRI will work with the Bachmann EZ-Command.  If it does, that's probably what you want.  Hardwiring an Athearn diesel will take at least an hour.  Make sure the motor is isolated.  There are some nasty springs.  Watch for the suckers.  Dissassembly is easier than assembly.
Gene

[buzzard975]

My Athearns is the older style (pre '89 I think) PA-1.  It doesn't have any springs....or wires for that matter.  It's a very simple design, so I figured it would be a good candidate for my first decoder install.  Yep - I understand that a decoder is supposed to isolate the motor from the power, and since the Athearn PA-1 get's power through the trucks and into the frame, I will have to make sure to isolate it.   Thanks for the reply.

[Tim]

Buzzard975

The springs Gene is talking about are the motor brush springs
that are retained by the copper strips on the top and bottom of the motor.

You will need to remove the bottom one and modify it to isolate the motor electrically.

The bottom retainer has two projections that make contact with the frame, they need
to be removed to isolate the motor.  Just putting tape under them is not sufficient.
They will in time penetrate the tape, good-by decoder.

The orange and gray motor leads will be connected to these copper strips.

The easy command can program a number from 0 - 9 to any decoder but cannot program "CV's".

Tim Anders
Souderton, PA

[buzzard975]

Awwww, I see.  Ok, that makes sense.  Yep - you're exactly right - I see those 2 prongs and the look like they would eat through tape in time.  I will Dremel them away.

I know the EZ command can't progam the CVs, what I meant is if I bought a programmer, would it be able to program the Bachmann decoder I mentioned.

Thanks a lot for the help!   

[buzzard975]

BTW, I found that just switching the lower and upper copper strips on the motor works great.  that way I get a perfectly smooth one on the bottom what I can easily isolate, and the metal prongs on the top should easy to solder wires to.

[Tim]

Buzzard975

The Digitrax PR-3 will connect to your computer and with JMRI decoderPro
software you can program any CV you want and print out a hard copy
for future reference.

PR-3:  http://www.digitrax.com/menu_computercontrol.php

DecoderPro : http://jmri.sourceforge.net/

Have fun

Tim Anders
Souderton, PA

[buzzard975]

Cool!  This stuff looks fun.  I'm total computer nerd (IT analyst) and this DCC stuff is a great way to combine my love of trains with my love of 1s and 0s. 

Thanks everybody for the info! 

[Jim Banner]

The Bachmann 44913 decoder does not have the necessary CVs for speed matching.  CV2 (start voltage) is implemented but CV5 (maximum voltage) and CV6 (midpoint voltage) are not.  Nor does it support a speed table.

Depending on the age of your Athearn PA-1, the decoder's current rating may be inadequate unless you install a later motor.  The PA-1 with a gun metal coloured, oval motor has a stall current approaching 2 amps.  The PA-1 with a gold coloured, flat sided motor is probably okay but be sure to check the stall current (as you should with all decoder installations.)

You can view the 1 amp decoder specs by clicking on the link below:
http://www.bachmanntrains.com/home-usa/ez_content/1_Amp_Decoder_Instr.pdf

Unfortunately, you cannot program anything except address and normal direction of travel with the E-Z Command.  Fortunately, your E-Z Command's range of controls is not limited by its programming capabilities.

JMRI (Java Model Railroad Interface) will NOT work with your E-Z Command but the PR-3 programmer will work with Bachmann and many other brands of decoder in addition to Digitrax.  As far as Decoder Pro goes, I am not sure if the definitions for the Bachmann decoders have been written yet.

It has just been pointed out to me that in fact the defintions are available at :
http://jmri.sourceforge.net/xml/XSLT/pages/decoderIndex.html

[buzzard975]

Glad you mentioned the stall amps Jim.  Again, being a newbie I assumed they were a bit overbuilt and would handle any loco.  Mine is the gold, flat-sided motor, so hopefully 1 amp will be enough.   I got one for $17  including shipping, so I won't have a lot at stake, which is good because I don't have a way to measure the stall amperage.   I guess if I hold the loco back and hit the throttle, and the decoder starts to sizzle and smoke, it's drawing more than 1 amp.   

I'm learning as I go, and these posts have been really helpful. 

[Rangerover]

The Bachmann 44913 decoder does not have the necessary CVs for speed matching.  CV2 (start voltage) is implemented but CV5 (maximum voltage) and CV6 (midpoint voltage) are not.  Nor does it support a speed table.

I received my Digitrax PR3 and I am using it with JMRI Decoder Pro and finding out that there are not many cv's changes you can make with the cheaper Bachmann decoders. More for the Spectrum though, am I doing something wrong or is that the way it is.

The more expensive loco's like Atlas, Athern, Broadway Limited, Proto and Stewart and especially those with sound seem to have many more cv's.

I did install a digitrax decoder in a 70 ton Bachmann Switcher and that seem to have most of the cv's the more expensive loco's have excluding of course those with sound.

Funny I just got into this more out of curiosity about cv adjustments, but I love it. I feel a little disappointed with not being able to do anything more with Bachmann, but after considering the cost of a DCC Bachmann engine for under $50.00, it's still a bargain. Bachmann, because of the price of an operating DCC simple system, started me in DCC.

I would think I could replace some  decoders in a few of my Bachmann Loco's with better decoders, some are great runners and I may try  sound decoder in a few of them.

[jward]

buzzard,
some notes from my experience with older (1975-1995) athearns......

first, it is unnecessary to remove the prongs on the bottom motor clip if you switch the clips. use the top motor clip on the bottom and vice versa. then all you will need to do is cover the bottom clip with electrical tape. i had many athearns so i had a spare clip to keep everything together.

about the motor brushes and springs.... the motor brush is shaped to fit around the spinning part of the motor. getting the brush out of this alignment will detract from the performance of the locomotive, so be very careful of the alignment of the brushes. on some athearns, the top of the brush has a little slot in it so that you can align it with a screwdriver. the slot should be in line with the motor shaft.

athearn wheels are sintered metal. as with the rest of the athearn pickup system, it works well on dc bot is finicky on dcc. you may want to replace the wheels with nickel silver ones from nwsl or jaybee. the pickup from the trucks to the motor uses a metal clip from the top of the motor to the tops of the trucks. don't try to modify the clip. solder directly to the contact bars on the top of the trucks. the trucks also use the pivot point on the frame and a hole in the truck bolster for the other side of the circuit. this pivot point is another weak link in the circuit when using dcc. you may want to bypass it by soldering directly to the metal plate in the truck that picks up power off the wheel bearings.

note that athearn's electrical contacts in the trucks are of a metal which is not easy to solder to. before attempting to do this, completely disassemble the trucks and use a couple of alligator clips as heat sinks so that you don't melt the plastic parts of the truck. an alternate method would be to drill and tap those contact plates to accept a small brass screw, and solder your wires directly to the screw.

as far as adjusting cv's goes. if your decoder supports speed tables, you can tweak those to get your locomotives to run together. i did mine by timing the locomotives over a 6 foot (2 lengths of flex track) section with a stop watch, calculating the speed difference as a percentage, then adjusting the speed table of the faster locomotive by that percentage. you always want to match your locomotives to the slowest one that you intend to use in a consist.

the athearn dcc conversion isn't the easiest if you want good reliable performance. but if you have the time and patience, you can make a decent  dcc locomotive out of them.

[Jim Banner]

jward, may I add a few comments to your excellent advice to buzzard.
- after soldering the decoder wire to the top clip on the motor, do not reinstall the long bar that went from the front truck to the top of the motor to the rear truck.  Seems obvious, but an earlier poster burned up several decoders just this way.
- do not connect the blue wire to the headlight bracket.  This is another sure way to burn up a decoder.  If you want to reuse the existing headlight, shorten the bronze leaf spring that touches the tip of the bulb so that it is well clear of the contact on the front truck, then solder the white decoder wire to the stub of the bronze spring.  Alternately, remove the bronze leaf spring and solder the white decoder wire to the tip of the bulb.  The return from the bulb is to the chassis of the locomotive and thence to the wheels.  This is called half wave lighting and is not only easy, it will prolong the life of the bulb.  Alternately, remove the headlight lens, ream the hole to 3/16" and install a 12 volt, 15 mA T-1.5 lamp in the original headlight hole.  No more lit up cab and a very realistic looking headlight.
- If you upgrade the wheels to NWSL, keep the old ones.  Sooner or later you will run into a Proto 2000 locomotive with split gears and you will have spares on hand.