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This question is for the people who are well versed in the internal components of the Athearn Genesis locos.
I have an Athearn Genesis SD70, my friend has an SD70 and a SD45-2, and another friend has an SD70.
My SD70 runs faster than all of my other locomotives on DC. (not converted to DCC yet) as does my second friend's loco.
My friend with the SD70 and the SD45-2 (both genesis), has Tsunami decoders in them.
The problem that all three of us have with genesis locos is that they start up really fast, and they accelerate really fast.
CV 2 is set at 0 for the ones on DCC. There is no way to slow them down. It's also impossible to modify the speed tables on the other locos to match the genesis locos because they have such a weird speed curve.
Now, my question is this. Is it the motor, or the gear ratio? If it's the motor, then I can just remotor the locos with Athearn RTR motors and I'd be all set. If it's the gear ratio, then does anyone make a regearing kit for Genesis locos to make them run similarly to Athearn RTR or Atlas?
I dont know the answer to your question, but the guy who produced this video on youtube had the same problem. Here is a link to it, and somewhere in here he had the same problem but with the original MRC decoder on an Athearn Genesis. He replaced it with a Tsunami and it worked as it should.
http://www.youtube.com/watch?v=_7agGTrtFfw&feature=related
Get in touch with Athearn. They are now using Tsunami decoders and may replace them at no cost.
I have a group of SD70's and have had no problems at all. The low speed and start up control functions are working just fine. Sound to me like a bad decoder. I've had more trouble with MRC decoders than any other.
As far as the DC unit, I haven't a clue. I doubt that you have a motor or drive problem, it just may be the nature of the beast. I'll let someone who has a DC unit elaborate more precisely on that one.
bob
I forget if you can lower the top speed of the MRC. If so then do that first. Then you can make a custom speed table to match. There are also other adjustments that can be made to the tsunami to match gearing differences but first you have to get the base loco slower.
Good Luck
I just shipped my F45 back to Athearn for MRC Decoder issues. In DCC mode it would sometimes not want to move, I would be up to 30-40 on the speed control (Digitrax system) and while the RPMs of the prime mover sound would increase, the engine would just sit there, then suddenly take off. In DC mode it would rarely if ever do this. It would also not respond to the hand held remote unless the remote's antenna was like 2 inches from the loco shell, we tried a new battery and did a factory reset on the main per Athearns instructions with any help to the engine. I hope it comes back with a Tsunami in it and not that MRC sound. The actual sound from the MRC unit was ok for me, but the motor control issues is not. Mike
Two on DC, two on DCC, belonging to three different people, with three different roadnames. (Mine is NS, my friend's 45 and 70 are Conrail, and the fellow club member's is BNSF)
If they run like that on DC, then it's not a DCC issue. With three different people having the same issue, I don't think we all got defective units (unless they are ALL defective)
I don't think it's an issue at all. With DC there's basically nothing you can do but live with it. With DCC there are good possibilities to speed match, even when the loco's have different gearing.
No, I can't speed match. The engines on DCC will run with each other, but nothing else because they have weird speed curves and run faster in general so the other brands would literally have to jackrabbit to catch up to them.
CV 2 is at 0 so theres no way to lower the start speed any more.
Anyone else know anything about them?
I emailed Athearn, but like my previous emails, it has not been answered.
Call Tony's Train Exchange. Although they are basically DCC gurus, they may have had some experience with DC Genesis units.
I removed the decoders in my SD70/75's to see if I could make heads or tails of your problem. Mine run just fine. When given power, at low throttle, they crawl along. I am having a mind to think that some other problem may exist with your units, I just can put my finger on the solution. Gearing should be the same on all SD70/75's, as well as having the same motor. I am tending to think that it is a controller problem or one with the power supply. Again, these have "control"/circuit boards and the problem could be there.
Don't give up on Athearn returning your message. It took a week for me to get an answer from them. Busy people. They may have you return the engine for repair/replacement. Make sure that you aren't getting replies that are filtered to your SPAM file. You can do so by adding them to your address book.
Bob
It can't be a controller issue unless all digitrax products cause the problem. I've tried it on the club layout and my home layout. The club uses a digitrax Super Chief, and I use a Zephyr.
I'll email tony's and see what they can tell me.
Thanks
Anyone else know anything about them?
I emailed Athearn, but like my previous emails, it has not been answered.
Athearn's service has been nothing less than spectacular for me. Give them a little more time. good luck with your issue.
Give Athearn a call, I have found email to usualy be about worthless with larger companies. My F45 came back yesterday via UPS, thats less than a full 7 days turn around from Cali. They intstalled a new decoder/sound board, still MRC, and included a new hand held remote. This board is working as it should and it didnt cost me anything other than shipping one way back to Athearn. While I wish they would have upgraded the engine to a Tsunami as I has requested. It does work as it should for now. If it acts up again. I will send it back again. Prior to shipping back, it wouldnt run in dual mode on a MRC Tech6, would take large amounts of throttle to begin moving in DCC mode and when it did move it would take off very fast. All typical MRC decoder issues. The word localy is the newer MRC boards are far better than what came originaly in the Athearn engines or aftermarket. But with the damaged reputation MRC's decoders have, only the deeply discounted sales will spur modelers to take a chance and buy them. I bought 2 EMD drop in boards for Athearn RTR's for under $80 for the pair. We shal see how they do. Hopefully with TCS getting into sound decoders, prices will come down on the other brands.
Ok, I'll give them a call sometime during the week.
No response from Tony's Trains.
The battery boxes, etc all came off when I tried to take the shell off (I think it's supposed to). Will Athearn take it back in that state? Or should I ask them before sending it back if they want me to send it back?
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