Bachmann Plus F7A-B Decoder DCC upgrade

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Hello all,

I am new to the forum and am hoping I can get some good insight and information from you folks.

I have read a fair amount of articles and forums on what I am about to ask but i have yet to really have my question answered.

I have a few Bachmann Plus F7A and B units that run great. Basically brand new. (one set was still shrink wrapped)

I want to know how to install a decoder in these for use with a new DCC system and what you guys may recommend in the way of the decoders themselves. I'm really not too interested in sound etc in this first attempt. If I can install the decoder and have it run properly that will be enough for the time being.

I understand that these engines are old and that many of you may say I am wasting my time. But I really want to do this not only for the sake of upgrading these models but also for the experience and learning how to do it.

I found this write up that someone did that I hope is a good start but it is dated 2010 and I want to be sure that this is still the correct way to do this Also it would have been great if this write up had pictures as this will be my first time attempting this.

http://www.digitrax.com/tsd/KB882/installation-of-digitrax-wired-decoders-in-bachman/


Can anyone help me out? Any information on this or direction as to where I can find a good tutorial would very much appreciated.

[jonathan]

kkm...

I have done exactly what you are planning.

For years Bachmann's F7A and F7B units have come "DCC Ready".

Once you have removed the screws on either side of the fuel tank, the shell will lift off. However, the shell may be a bit sticky the first time you remove it. Also, one CAN remove the shell without removing the front coupler, but it's an easier operation if the coupler is removed.

You will see a "dummy" plug on top of the motor section.  This is removed and a decoder is plugged in to the 8-pin receptacle. Easy as that.

I used the standard Bachmann EZ command decoders for my 3 units. Any standard motion decoder will work... just make sure the decoder has an 8-pin connector, or you can solder on a connector yourself.

Somewhere, in the not-too distant past, I posted a few threads on my F7 projects... with pictures.  Don't have the time for a search at the moment.

Regards,

Jonathan

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Hey Jonathan,

I appreciate the reply.

However, I believe the units I am talking about (Bachman Plus F7A-B) are not DCC ready. I believe they are going to need to be hardwired. These are very old units.

Thank you

[WoundedBear]

There is nothing wrong with the instructions in the link you provided. No secret tricks......just break out some tools and get at it.

Sid

[Len]

The Digitrax instructions call for using the existing chassis 'ground' connection for one side of the motor connection. If you want to fully isolate the motor these instruction on the TCS site show how: http://tcsdcc.com/Customer_Content/Installation_Pictures/HO_Scale/Bachmann/EMD%20F9/EMD_F9.html

Their for the Bachmann F9, but the chassis is close enough to the F7 not to make much difference.

Len

[Bucksco]

http://www.bachmanntrains.com/home-usa/board/index.php/topic,27726.0.html

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@ LEN,

What would be the benefits of fully isolating. The link that you sent with the decoder being installed in the Santa Fe engine, would that be very similar to my engine? Should I go by these instructions instead of the ones I originally posted?

Thank you guys. Very helpful

[Len]

With DCC using the chassis as for one side of the motor connection can result in "not good things" happening to the decoder if the chassis hits the rails during a derailment. By isolating the motor connections, that potential problem is eliminated. From the pics I've seen, the F9 chassis in the instructions is close enough to the F7 that there shouldn't be much, if any, difference in the installation.

Whether you follow the Digitrax or TCS instructions is up to you. Either way will work, but there is a potential risk, however slight, with the Digitrax method.

Len

[[email protected]]

Thank you very much. That makes perfect sense.

Can you recommend a TCS decoder? The link for the TCS T1 Decoder is invalid.

Thank you

[dutchbuilder]

Always isolate the motor.
Better be safe than sorry.
The motor is fed by a separate circuit from the decoder and does not like the "AC" from the track.

Ton

[rich1998]

A few years ago I did a couple split frame HO locos and isolated the motor contacts from the frame. The hardest part was keeping track of all the parts between the frame halves.

One loco required Kapton tape on the motor because the motor brushes contacted the motor frame halves which where bolted to the frame halves and needed nylon screws, not metal screws.but the loco was not a Bachmann product but I digress.

Rich

[Len]

Thank you very much. That makes perfect sense.

The TCS decoder instructions apply to any manufacturers hardwired decoder you might want to use, not just their T1 decoder. There is an NMRA standard for decoder wiring colors. If you really want to use the T1 the link is here: http://tcsdcc.com/1484 Other decoders can be looked at by clicking the 'Product' link at the top of the T1 page.

You might want to check several manufacturers listings, Bachmann, Digitrax, Lenz, NCE, TCS, etc., before deciding on which one to use.

Len

[Trackbump]

Check the axle gears and drive shaft couplings before you sink time and money into these with decoders because they all split right out of the box because of time and the resin they are made from over time cracks when it is mated with metal worm shafts and axle half shafts common problem with the older ones that created a bad rep.. They are problematic parts when new back in 1989I Believe when plus was made.Same trucks ,but better parts. Bachmann has upgraded parts  since that will cure the problem and are available.

Adam

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Thank you guys very much.

Could anyone of you guys help me out with an article or review that helps explain which decoder to use for certain trains? and maybe why I would choose a certain brand over another.

Thank you

[Len]

If all your looking for is motor and light control, no sound, it pretty much pretty much comes down to personal preference and size.

Forget the 'HO', 'N', etc., designations. For most HO locos you'll want a decoder rated for at least 1 amp, and that will fit the space in your loco. As long as it's rated 1 amp, or better, you may find an 'N' or 'Z' decoder is the best fit for whatever you're working on.

Personally, I tend to use TCS decoders. Not because there's are better than anyone else's, but their documentation is a lot easier to understand for those of us who aren't "DCC Geeks".

Len