Another decoder question
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stang_crazy
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I may be wrong but i thought the athearn genny SD70's had decoders in em? Or you wanting to put in a different decoder?
ThoroughBreed
Dcc~detail~diesel freak
If this is for the HO scale, then its also according to the "phase" of the Athearn model as to what is inside them. None of them come with a decoders installed, unless the vendor puts one in. As for the different phases from the manufacturer, the first editions of the sd70's are dcc ready in that the wiring is compliant for a new drop in replacement board. The second generation has a 9 pin plug for a decoder and the newest generation has both a 9 pin and a 8 pin plug. The last 2 generations are setup to control the 1.5v bulbs that are installed in the loco right from the dcc-ready board thats from Athearn. With these all you have to do is drop in a decoder and the dcc-ready board will control the lights.
The first generation board has to be completely replaced with a decoder that will have outputs for the 1.5v bulbs or you have to replace those bulbs with a substitute that will match the decoder.
I hope this helps with what you are asking.
The first generation board has to be completely replaced with a decoder that will have outputs for the 1.5v bulbs or you have to replace those bulbs with a substitute that will match the decoder.
I hope this helps with what you are asking.
ThoroughBreed
Dcc~detail~diesel freak
Heres how to identify the generations of the loco; If you have to put on the handrails and all the detail parts, then this is a first generation. If you dont have to install any detail parts and its more or less a R-T-R, then its safe to assume its a second generation at least.
If you have at least a second generation, then its safe to buy a 9 pin decoder. I'd personally use a NCE D13SRJ for it. Its a cheap and capatable decoder that will have no problems with the loco, and it will have the extra functions for the ditch lights to flash independently.
EDIT: If this is a first generation loco, then I'd use a TCS A6X or a NCE DASR decoder mfor it as they both have the capabilities of the 1.5v bulbs.
If you have at least a second generation, then its safe to buy a 9 pin decoder. I'd personally use a NCE D13SRJ for it. Its a cheap and capatable decoder that will have no problems with the loco, and it will have the extra functions for the ditch lights to flash independently.
EDIT: If this is a first generation loco, then I'd use a TCS A6X or a NCE DASR decoder mfor it as they both have the capabilities of the 1.5v bulbs.
First run Genesis SD70Ms need the light board replaced, but that is pretty simple if you buy the right replacement decoder, the original board just pops off. If you go with say a Digitrax DH165A0 it will install easy Here is a pdf of the install http://www.digitrax.com/ftp/DH165A0.pdf DH165A0 fits Athearn Genesis, Kato, Stewart, Atlas & Other HO Locomotives.
Later runs of the Genesis SD70Ms have a DCC ready light board and come with a 9 pin decoder socket.
Soundtraxx makes a Tsunami sound board for these for around $80 shipped from places like www.litchfieldstation.com
Jerry
Later runs of the Genesis SD70Ms have a DCC ready light board and come with a 9 pin decoder socket.
Soundtraxx makes a Tsunami sound board for these for around $80 shipped from places like www.litchfieldstation.com
Jerry
ThoroughBreed
Dcc~detail~diesel freak
I dont want to argue or burst your buble about the 165A0 or even the 163K0, but they will not controll the athearn dual 1.5v bulbs of the genesis units. They will only control a single bulb, as they are 20ma bulbs and will overload the decoder as its only rated at 15ma's, and for using the other functions for the ditch lights, you will have to use resistors or completely change it them out with leds and resistors to use them.
I bring up the other types of decoders as they are the easiest to use and substitute and to keep the 1.5v bulbs in place. The beginning dcc modeler need not be discouraged by installin those decoders only to find out they will either blow the bulbs or not work at all, and then they have to change the bulbs or put in leds and resistors to get them to work.
When you use the dual 20ma lights wired in parallel, the amperage requirement doubles to 40ma's and the is above the load for the F0 and F1 functions (forward and reverse lights) and you will have to wire only a single bulb in both directions.
I bring up the other types of decoders as they are the easiest to use and substitute and to keep the 1.5v bulbs in place. The beginning dcc modeler need not be discouraged by installin those decoders only to find out they will either blow the bulbs or not work at all, and then they have to change the bulbs or put in leds and resistors to get them to work.
When you use the dual 20ma lights wired in parallel, the amperage requirement doubles to 40ma's and the is above the load for the F0 and F1 functions (forward and reverse lights) and you will have to wire only a single bulb in both directions.
Good information to have because you don't want to have to replace those bulbs. Didn't know that about the Digitrax. TCS A6X or a NCE DASR decoder would be a better choice then.
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ThoroughBreed
Dcc~detail~diesel freak
Glad to know that you arent taking offense to this and will realise the good information presented here. Thanks
I know of this info from experience with those decoders and have read all 3 of the manuals that deal with them (the basic digitrax decoder manual, the fx3 manual, and the decoder specific manual), and I have to say that after reading all of that, it definitely leaves you confused.
I have a degree in Electronics and have worked with simple digital systems, and those manuals are for the die-hard digitrax fans, lol.
I definitely do not recommend using the digitrax decoders as of current for those genesis locos as none of them are compliant with the athearn bulbs right now. I do believe they are probably working on that with maybe some revisions of the current models and adding a few others, but as of right now they arent.
That being said, I now have opended up a big can of worms for all the responses that will come, lol. But, seriously, it says that max amperage in the specs for those decoders that they wont handle above 15ma so, I'll leave it at that.
Thanks for listening
I know of this info from experience with those decoders and have read all 3 of the manuals that deal with them (the basic digitrax decoder manual, the fx3 manual, and the decoder specific manual), and I have to say that after reading all of that, it definitely leaves you confused.
I have a degree in Electronics and have worked with simple digital systems, and those manuals are for the die-hard digitrax fans, lol.
I definitely do not recommend using the digitrax decoders as of current for those genesis locos as none of them are compliant with the athearn bulbs right now. I do believe they are probably working on that with maybe some revisions of the current models and adding a few others, but as of right now they arent.
That being said, I now have opended up a big can of worms for all the responses that will come, lol. But, seriously, it says that max amperage in the specs for those decoders that they wont handle above 15ma so, I'll leave it at that.
Thanks for listening
ThoroughBreed
Dcc~detail~diesel freak
The bulbs arent different, but the boards in the locos are. The original genesis sd70 series locos came before the ath rtr did and as such the dcc-readiness of the loco is the question we are discussing here.
I have quite a few of the rtr sd50/60 class locos and they all use the same 2nd generation dcc-ready board in them. They will take a 9 pin decoder easily, and actually have the pin-out for the 8pin, but unless you want to do some seriuos soldering, you cant use a 8 pin in that socket.
The decoders in question are the dh165a0's which completely replace the light board in the genesis units. Those decoders arent ath 1.5v bulb ready like the others that are listed.
I do need to make an addendum to the listed replacements also:
the NCE DASR will only handle one bulb also for the outputs of all the functions including the forward and reverse lights. I remember setting up 2 of the aux functions to act along with the forward and rear light function to accomodate the second bulb in the lights.
So, I will say that the TCS A6X in my opinion, is the best decoder to replace the first generation boaqrds in the genesis series if you want to keep all the original bulbs, and use the ditch lights, and not have to install a bunch of resistors. Whew. thats a mouth full, lol.
I have quite a few of the rtr sd50/60 class locos and they all use the same 2nd generation dcc-ready board in them. They will take a 9 pin decoder easily, and actually have the pin-out for the 8pin, but unless you want to do some seriuos soldering, you cant use a 8 pin in that socket.
The decoders in question are the dh165a0's which completely replace the light board in the genesis units. Those decoders arent ath 1.5v bulb ready like the others that are listed.
I do need to make an addendum to the listed replacements also:
the NCE DASR will only handle one bulb also for the outputs of all the functions including the forward and reverse lights. I remember setting up 2 of the aux functions to act along with the forward and rear light function to accomodate the second bulb in the lights.
So, I will say that the TCS A6X in my opinion, is the best decoder to replace the first generation boaqrds in the genesis series if you want to keep all the original bulbs, and use the ditch lights, and not have to install a bunch of resistors. Whew. thats a mouth full, lol.
ThoroughBreed
Dcc~detail~diesel freak
I suggest the TCS A6X because I'm the type of person who wants to use all the available lighting prospects for all locos I get, and the A6X will use the original bulbs for forward and reverse andx also setup the forward ditch lights for flashing and use in either rule 17 or other, to include switcher mode, with an on board voltage regulator for all the lights to use.
ThoroughBreed
Dcc~detail~diesel freak
The first generation of the dcc-ready boards dont have a 8 or 9 pin socket on them; the second generation has both a 8 pin and 9 pin socket, but the 8pin socket isnt "to size" to accept a 8 pin decoder unless you solder a 8 pin height adapter into the socket to accpet the decoder with it wiggling around loosely.
I hope that explains it, lol.
edit: the punchout is there and the connections are active, but the socket is not on the board and as such the decoder will just wiggle around in the "punch-out" and not seat firmly to make any connections.
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I dont want to argue or burst your buble about the 165A0 or even the 163K0, but they will not controll the athearn dual 1.5v bulbs of the genesis units. They will only control a single bulb, as they are 20ma bulbs and will overload the decoder as its only rated at 15ma's, and for using the other functions for the ditch lights, you will have to use resistors or completely change it them out with leds and resistors to use them.
<<Snip>>
When you use the dual 20ma lights wired in parallel, the amperage requirement doubles to 40ma's and the is above the load for the F0 and F1 functions (forward and reverse lights) and you will have to wire only a single bulb in both directions.
This is incorrect. Not sure where you got your numbers but Digitrax lighting functions are rated for a total of 500 milliamps. You can power dual bulbs (and I have) off of any single function. You will probably have to add limiting resistors unless you are powering them through the factory board using it's current limiting circuitry. Go to the Digitrax site and look at their decoder specs. Function output in milliamps is pretty much the same across the brands (Digitrax/NCE/TCS Soundtraxx) The Athearn bulbs are about 15 millamps, and a 1/4 watt 1K ohm reisitor works well with them if you have to use a resistor.
ThoroughBreed
Dcc~detail~diesel freak
From page 6 of that exact decoders manual:
If you cut the "adj" line, the voltage jumps upto the track voltage for that output. It will accomodat a single bulb the way it is, but if you cut that, then you have to use a resistor now. With the differences among the dcc systems track voltage, as there is no standard there, the resistor could be anything from a 200 ohm to a 1k, so thats why I suggested the other decoders for the ease in applying them for the beginners or for the people like me whom just want to run trains and not have to sit and think about why they run at the voltage and how can I add the other bulbs for the ditch lights to work right.
I suggested the decoder also because in my opinion, its a better decoder all around.
The DH165A0 is configured to control the forward-headlight F0F/white lead
and reverse-headlight F0R/yellow lead for directional lighting. These two headlight
function leads are current regulated for LEDs or lamps, with factory setting
of approx 15mA, with no resistors required. Cut the ADJ link to increase
headlight current to approx 30mA- see fig 4.and reverse-headlight F0R/yellow lead for directional lighting. These two headlight
function leads are current regulated for LEDs or lamps, with factory setting
of approx 15mA, with no resistors required. Cut the ADJ link to increase
If you cut the "adj" line, the voltage jumps upto the track voltage for that output. It will accomodat a single bulb the way it is, but if you cut that, then you have to use a resistor now. With the differences among the dcc systems track voltage, as there is no standard there, the resistor could be anything from a 200 ohm to a 1k, so thats why I suggested the other decoders for the ease in applying them for the beginners or for the people like me whom just want to run trains and not have to sit and think about why they run at the voltage and how can I add the other bulbs for the ditch lights to work right.
I suggested the decoder also because in my opinion, its a better decoder all around.
OK, I understand now. When you said the deocoder function was not rated for more than 20 ma I didn't realize thare was an on board current limiter. I don't use this board...All my Genesis F's are either getting Tsunamis or have NCE DASR's. Total function current remains at 500 ma, and with these 6 function decoders you have to watch how many and what millimap bulbs you use or you can overload the decoder if you turn on enough lights!
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