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Athearn Genesis F3 DCC Ready - Choosing the Right Decoder

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Athearn Genesis F3 DCC Ready - Choosing the Right Decoder
Posted by richhotrain on Thursday, April 14, 2022 6:46 AM

I bought a pair of DCC Ready Athearn Genesis F3AB locomotives. I am a bt confused about selecting the right non-sound decoder for each locomotive.

Here are the instructions from Athearn.

Here are photos of the "DCC Jumper Board" still in place in the first photo and removed in the second photo. As you can see, the circuit board has a 21-pin configuration.

So, the Athearn instructions say to "plug in a decoder with either a 9-pin plug or an 8-pin plug". But, the circuit board has that 21-pin configuration in place.

Can someone help me sort this out?

Rich

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Posted by tstage on Thursday, April 14, 2022 7:33 AM

Looks like a 21-pin to me, Rich.  You could always call or email Athearn to verify and let them know of the error on the instruction sheet.

Tom

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Posted by richhotrain on Thursday, April 14, 2022 8:01 AM

tstage

Looks like a 21-pin to me, Rich.  You could always call or email Athearn to verify and let them know of the error on the instruction sheet.

Tom 

Thanks, Tom, I will do that. I wonder if the instructions are from an earlier run, although these locos have LED lighting which is a welcome change from those crappy incandescent bulbs.

So, do I need a decoder with a 21-pin connector? I assume that is the case.

Rich

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Posted by tstage on Thursday, April 14, 2022 8:05 AM

I have an Athearn Genesis F3A-B that was given me by Ed and it came with an 8- or 9-pin socket.  Yours has to be a newer run.

Yea, from the photo you're going to need a 21-pin decoder, Rich.  I would go either TCS or LokPilot for a motor-only install.  I used a TCS A4X in my B-unit and a TCS WOW WDK-ATH in the A.  They run very well and smoothly.

Tom

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Posted by wrench567 on Thursday, April 14, 2022 8:17 AM

  Rich.

 It looks like Athearn upgraded the motherboard but not the instructions. They did the same thing going from the 8 pin to the 9 pin JST.

  When I was doing installs for club members, one guy gave me a pair of locomotives and two 8 pin decoders for them. Upon opening them up one was 8 pin the other was 9 JST. Both bought at the same time. Kind of like a box of chocolate. You never know what you'll get.

   Pete.

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Posted by wrench567 on Thursday, April 14, 2022 8:28 AM

  Rich.

  Looking at the motherboard, it appears to be mounted backwards. The FO is on the opposite side of the cab. There is also solder pads for a speaker. Very easy to add sound if you want.

   Pete.

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Posted by riogrande5761 on Thursday, April 14, 2022 8:31 AM

A Nix Decoder Buddy circuit board may allow you to adapt a 21 pin to a 9 pin. 

Rio Grande.  The Action Road  - Focus 1977-1983

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Posted by wrench567 on Thursday, April 14, 2022 10:43 AM

riogrande5761

A Nix Decoder Buddy circuit board may allow you to adapt a 21 pin to a 9 pin. 

 

  A decoder buddy is not necessary. A decoder buddy is used for converting older 8 or 9 pin locomotives to a 21 pin decoder. It has solder pads for accessory lighting, speaker, and some have a keep alive solder pads. Their latest board has a socket with lighting solder pads to allow complete shell removal. (Nice feature). The mini works great for locomotives without a lot of room. I have it on good authority that an even smaller version that uses the Next 18 nano decoders in the works.

    Pete.

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Posted by richhotrain on Thursday, April 14, 2022 11:03 AM

Here is what still confuses me. In the past when I have converted a DCC Ready loco to DCC and the factory installed circuit board has an 8-pin plug, the plug itself has 8-pins (male) and the circuit board has an 8-pin receptor (female). So, the plug is removed and a harness from the decoder has an 8-pin connector (male).

But, in this instance, the circuit board has a 21-pin receptor (male), and the plug has a 21-pin connector (female). So, when I remove the 21-pin plug to install a decoder, I will need a 21-pin connector (female). How do I deal with this? What decoder would I use?  Would I need a special harness?

Rich

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Posted by wrench567 on Thursday, April 14, 2022 12:10 PM

Rich.

  The Athearn motherboard has a black plastic cover over the pins. Carefully work it up from end to end. It's there to keep the pins from getting bent. Then match up the decoder and press firmly.

Any 21 pin decoder will work.

    Pete

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Posted by wrench567 on Thursday, April 14, 2022 12:17 PM

  Rich.

 I'm sorry. Looking at the second photo again I can clearly see the bare pins so there is no cover. Notice the one missing pin? The decoder socket will have a blank spot where that missing pin should be.

   Pete.

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Posted by blabride on Thursday, April 14, 2022 12:50 PM

For all of my Genesis F units I have used either the Soundtraxx ECO PNP for the older boards or the Soundtraxx ECO-21PNEM. In your case the ECO-21PNEM would be a good plug in if you want sound. If not any 21 pin, like the Soundtraxx MC1H104P21 or any of the ESU 21 pin Lokpilots. The Soundtraxx is much cheaper though. 

Good news with that board if it is a newer version with LEDS you don't need to worry about blowing bulbs and they are much easier to add decoders to. 

The big issue I have had in adding sound to these Units is what to do about a speaker. While there is a lot of room back there the speakers on the market tend to be to big or to small to fit right. I have used and like the Scale Sound Systems speakers made to custom fit this space. They sound amazing as well. There are several You Tube videos comparing these.

SB

 

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Posted by richhotrain on Thursday, April 14, 2022 1:01 PM

wrench567

  Rich.

 I'm sorry. Looking at the second photo again I can clearly see the bare pins so there is no cover. Notice the one missing pin? The decoder socket will have a blank spot where that missing pin should be.

   Pete. 

No worries, Pete. Your ealier post prompted me to go take a closer look at that circuit board setup. As I looked closely, it seemed that there was no way that 21-pin receptor on the circuit board could be a black plastic cover over the pins. So, your latest post confirms that fact.

Rich

 

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Posted by tstage on Thursday, April 14, 2022 1:22 PM

blabride
I have used and like the Scale Sound Systems speakers made to custom fit this space. They sound amazing as well. There are several You Tube videos comparing these.

I've installed a couple of the SSS speakers in a pair of brass locomotives and agree that they sound terrific.  I really appreciate all of the time & effort JT has put into optimizing the 3D printed baffles with the speakers.

Tom

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Posted by richhotrain on Thursday, April 14, 2022 1:31 PM

blabride

For all of my Genesis F units I have used either the Soundtraxx ECO PNP for the older boards or the Soundtraxx ECO-21PNEM. In your case the ECO-21PNEM would be a good plug in if you want sound. If not any 21 pin, like the Soundtraxx MC1H104P21 or any of the ESU 21 pin Lokpilots. The Soundtraxx is much cheaper though. 

Thanks for that infor, blabride. 

The Soundtraxx MC1H104P21 looks like the decoder that I am looking for. So, that connector is a female connector that will fit over the (male) pins on the motherboard?

Before I read your post, I was considering the Digitrax DH126MT decoder. I assume that decoder would work as well.

Rich

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Posted by gmpullman on Thursday, April 14, 2022 1:34 PM

tstage
I've installed a couple of the SSS speakers

+2 on the Scale Sound Systems speakers. I put my first pair in an Athearn Genesis F3 A & B and was convinced these were the best sound improvement money could buy! I've replaced over two-dozen former supposedly "deep bass" speakers now with the SSS units. 

Rich, read the instructions carefully when you do settle on a 21 pin decoder. Some install with the pins passing THROUGH the board then into the socket. This seems contrary to logic but it is the way they're designed.

See page 26 here:

https://soundtraxx.com/content/Reference/Manuals/Tsunami2/Installation-Guide.pdf

I know some of my Soundtraxx and TCS motherboard/decoder combos were this way.

Good Luck, Ed

 

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Posted by richhotrain on Thursday, April 14, 2022 1:39 PM

gmpullman

Rich, read the instructions carefully when you do settle on a 21 pin decoder. Some install with the pins passing THROUGH the board then into the socket. This seems contrary to logic but it is the way they're designed.

Ed, I'm not sure that I follow you. What do you mean by "through the board into the socket"?

Rich

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Posted by wjstix on Thursday, April 14, 2022 1:47 PM

For an 8-pin connection, generally the 'female' receptacle is built into the lightboard, and the decoder (or it's harness) has the 'male' eight pins. 21-pin connections are the opposite, the pins are in the lightboard and the decoder has the holes that the pins go in to.

Unfortunately I can't see the OP's pic, but note that some engines made in recent years have options to plug in a 21-pin decoder and an 8-9 pin decoder too.

Note that the OP is asking about a non-sound decoder....

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Posted by gmpullman on Thursday, April 14, 2022 1:55 PM

richhotrain
What do you mean by "through the board into the socket"?

When I got my first 21 pin decoder some years back I studied the newfangled thing for quite a while. My inital "assumption" was to place the black socket on the decoder facing the pins the way any ordinary plug and socket combination would seemingly work.

After studying the situation and the documentation for a while it suddenly dawned on me that the decoder had to be placed onto the "motherboard" with the PC board in the same orientation. In other words the gold pins passed through the bottom of the decoder then engaged the black plastic plug which is now oriented on the top side or facing up.

See the Soundtraxx guide I linked to above, Pg. 26.

Of course the index pin will help answer alignment issues but it had me scratching my head for a while. IIRC, the TCS decoder had a little piece of Kapton tape over the "NO" side of the plug.

DCC documentation from nearly ALL the major decoder manufacturers is awful, at best. Dave (HOn3 Critter) had a keep alive diagram that had the + and — pads reversed. Soundtraxx confessed that, yes, maybe some were shipped with the wrong hookup drawings but, well, sorry.

Good Luck, Ed

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Posted by wrench567 on Thursday, April 14, 2022 2:59 PM

  Rich.

 There are two rows of pins. In the second photo you can see a pin missing on the left corner nearest the cab. The decoder will have a blanked out socket in the missing pins location. Look at the 21 pin jumper board removed and you should see what I mean. Actually the decoder will mount in the same orientation and location as the jumper plug.

  Have you considered a TCS decoder? Really excellent motor control. A Locpilot would be nice too. It has the automatic BEMF adjustment that gets good results.

    Pete.

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Posted by richhotrain on Thursday, April 14, 2022 3:34 PM

wrench567

Have you considered a TCS decoder? Really excellent motor control.  

Hi Pete. Yes, I have looked at TCS. I love their website, especially the section on Installations. The non-sound decoders can be expensive though. I will take another look. Any suggestions?

Rich

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Posted by richhotrain on Thursday, April 14, 2022 3:42 PM

gmpullman
 
richhotrain
What do you mean by "through the board into the socket"? 

When I got my first 21 pin decoder some years back I studied the newfangled thing for quite a while. My inital "assumption" was to place the black socket on the decoder facing the pins the way any ordinary plug and socket combination would seemingly work.

After studying the situation and the documentation for a while it suddenly dawned on me that the decoder had to be placed onto the "motherboard" with the PC board in the same orientation. In other words the gold pins passed through the bottom of the decoder then engaged the black plastic plug which is now oriented on the top side or facing up.

See the Soundtraxx guide I linked to above, Pg. 26.

Of course the index pin will help answer alignment issues but it had me scratching my head for a while. IIRC, the TCS decoder had a little piece of Kapton tape over the "NO" side of the plug.

DCC documentation from nearly ALL the major decoder manufacturers is awful, at best. Dave (HOn3 Critter) had a keep alive diagram that had the + and — pads reversed. Soundtraxx confessed that, yes, maybe some were shipped with the wrong hookup drawings but, well, sorry.

Good Luck, Ed 

Thanks, Ed. Now I see what you are saying.

This is my first experience with a 21-pin setup. Up until now, whenever I read about 21-pin decoders, I thank my lucky stars that I don't have to concern myself with them. Payback time has arrived!

Interestingly, or maybe not, I have two other pairs of Athearn Genesis F3s, both with factory installed sound (Soundtraxx Tsunami). Both pairs came with shells attached, so I have no idea what the chassis look like with the shells removed. I don't know if the decoders are 8-pin, 9-pin or 21-pin. Now, I am curious, but I will leave it at that.

Rich

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Posted by richhotrain on Thursday, April 14, 2022 3:45 PM

wjstix

For an 8-pin connection, generally the 'female' receptacle is built into the lightboard, and the decoder (or it's harness) has the 'male' eight pins. 21-pin connections are the opposite, the pins are in the lightboard and the decoder has the holes that the pins go in to.

Thanks for that explanation, Stix.

Rich

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Posted by wrench567 on Thursday, April 14, 2022 5:44 PM

  Rich.

 Lichfield Station lists the EU621 six function decoder for under $40. They also have the EU821 eight function for a little more. I can't see how many functions you need.

    Pete.

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Posted by richhotrain on Thursday, April 14, 2022 6:05 PM

wrench567

  Rich.

 Lichfield Station lists the EU621 six function decoder for under $40. They also have the EU821 eight function for a little more. I can't see how many functions you need.

    Pete. 

Thanks again, Pete, for your help and advice. It is most appreciated. 

I did go back and look at the TCS website, and I saw that EU621. When I read the Description, it said that "this decoder is designed specifically to meet the needs of European HO scale modelers". This statement made me wonder if this decoder would work for North American models.

But the Description did go on to say that "This decoder is compliant with the NEM660 standard found in locomotives equipped with the MTC 21-pin socket. So, I guess that the EU621 would work. The TCS price of $51.95 scared me off, but the Litchfield price under $40 that you found seems more reasonable for a non-sound decoder. 

As far as functions, I am not looking for much. The A-unit has two headlights but they are wired together, so there is no functional Mars light. There is also a backup light. So, a 2-function non-sound decoder would be just fine.

Rich

 

 

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Posted by wrench567 on Thursday, April 14, 2022 6:29 PM

   Hi Rich.

  The 21 pin is a European design. It's slowly getting incorporated into the North American market. Because it's a European standard is why most manufacturers call it an EU decoder. Just a few years ago you could only find them in European made locomotives. I can imagine in a few years that 8 and 9 pin decoders will be rare as hens teeth. Soon there will be 10 and 12 function decoders and they will come out with thirty pin decoders.

    Pete.

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Posted by OldEngineman on Thursday, April 14, 2022 10:04 PM

2nd photo from top shows the way the "dcc ready" engine came out of the box, right?

If so, the 21 pin board is a "dummy" board, when it's in place the loco is set up for DC-only operation.

For dcc, buy a 21 pin decoder. Then, just lift off the dummy board (BE VERY CAREFUL removing it, lift it "straight up and evenly" so as not to bend the pins), then set the dcc board over the pins (again, be careful), then "press home".

You'll note that the decoders are designed so that the pins "come through the bottom of the board" and settle into the plastic receptacle which is ABOVE the board.

The new board goes on the way the old one came off -- pins through the bottom, plastic receptacle on top. At least on the ones I've used (ESU).

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Posted by gmpullman on Thursday, April 14, 2022 11:49 PM

wrench567
Soon there will be 10 and 12 function decoders and they will come out with thirty pin decoders.

Next18 also PluX-22 on the horizon. Not necessarily more pins but smaller interface.

https://dccwiki.com/Locomotive_Interface

George has a little blurb here about how the guts have evolved over the years:

Also in the last few minutes he shows plugging in a 21MTC decoder.

Good Luck, Ed

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Posted by richhotrain on Friday, April 15, 2022 5:44 AM

OldEngineman

2nd photo from top shows the way the "dcc ready" engine came out of the box, right?

If so, the 21 pin board is a "dummy" board, when it's in place the loco is set up for DC-only operation.

For dcc, buy a 21 pin decoder. Then, just lift off the dummy board (BE VERY CAREFUL removing it, lift it "straight up and evenly" so as not to bend the pins), then set the dcc board over the pins (again, be careful), then "press home".

You'll note that the decoders are designed so that the pins "come through the bottom of the board" and settle into the plastic receptacle which is ABOVE the board.

The new board goes on the way the old one came off -- pins through the bottom, plastic receptacle on top. At least on the ones I've used (ESU). 

Thanks for that post, Old Engine. That pretty much confirms what I have concluded from all of the great replies to my initial post. I appreciate your information.

Rich

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Posted by tstage on Friday, April 15, 2022 5:58 AM

gmpullman
Next18 also PluX-22 on the horizon. Not necessarily more pins but smaller interface.

My Walthers Mainline NW2 switcher came outfitted with a Next18 socket.  While the socket was indeed small, it wasn't difficult to plug a Loksound micro Next18 decoder into it and sounds GREAT with the Scale Sound Systems speaker designed for it.

Tom

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