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Quick answers for DCC Decoders (has been answered). "Working coupler" thread now seperate.

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Posted by rrinker on Friday, November 21, 2014 6:55 AM

 Well, if you don't actually need AMPS - how many mA do you need? Decoder specs are all over the place, since the most common use of the functions is for lights or LEDs, with even typically used incandescent bulbs being about 30ma each and LEDs of course being much lower. MOST decoder will sink up to 100ma per function output, however there are also total limits - for example, you might see a decoder that has 4 total functions, each capable of 100ma, but the total load on the function lines cannot be more than 300ma, so obviously you can run all 4 at maximum. Others will do 150ma per, or 200ma per, not to exceed 500ma total. Or various combinations thereof, at least for HO and N scale size decoders.

 The cost to make the pulse generator circuit shouldn;t be that high - depending ont he rest of the circuit, you might be able to condense it all to a single 8 pin PIC with a couple of support components - those chips are cheap, only a buck or so. The REST of it - a bridge rectifier, filter capacitors, maybe a transistor or two to boost the output, some resistors, will probably cost more than the micro.

 As for DCC uncoupling, it's been done, a dozen different ways. Dick Bronson showed me his design at the Timonium train show some 10 years ago. His used regular Kadee couplers, so you could couple back up easily - unlike the modified from hi-rail design MTH uses where the knuckles tend to not close unless you couple up HARD.

                   --Randy

 


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Posted by richg1998 on Thursday, November 20, 2014 9:04 PM

For the OP. There are NO CHANNELS in decoders. You are applying your own terminology. There are functions in decoders. It would be better if you keep using the same terms in your discussions.

Someone mentioned that a few messages ago.

Rich



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Posted by richg1998 on Thursday, November 20, 2014 9:01 PM

farrellaa

 

 
PM Railfan
 
maxman

Sounds to me like he is asking about an accessory decoder, and possibly wants it to do something other than operate a locomotive.

But, I could be wrong.

 

 

 

Your not wrong, yet very warm. I want to be able to use my device on both cars AND locos, so it wouldnt be an accessery decoder. I am however driving accessories with it. Which is why your warm.

 

 

 

 

OK, how about remote couplers? (:}

That is a subject for another thread. DDC couplers are being discussed in the MRH forums. Suggest you don't try to hijack a forum.

Rich

 

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Posted by PM Railfan on Thursday, November 20, 2014 8:43 PM

rrinker

 Plus keep detailed records including dates of everything you design, then when you apply for a patent it won;t matter that someone else built something similar, as long as you have unrefutable proof that your design predates theirs.

 The 2 size pulses are still a problem even if the circuit draws milliamps instead of amps. No one's decoders really do that. Hence the interface circuit. Which could also have a rectifier and filter to get 1 amp+ in DC from the track, if needed.

                    --Randy

 
Oh most definately! This is such a simple project it only takes one JPEG to show it all (no moving parts!). Though i do concur, maybe a detailed report to accompany the picture would be prudent. Alas, the info is already on the pic. Anyone with a simple understanding of electronics could look at it and tell what im doing, in detail even.
 
I get ya on the 2 pulses. Thats the whole thing i was afraid wouldnt exist on a decoder that DID actually have aux channels. If that even existed to begin with. Which, now I know doesnt. BUMMER!
 
Pretty much, from all you've said, it is starting to look like either i redesign the pulses, OR, make the circuits your telling me about. I really dont want to have to include 'extra' electronics in this as Im afraid it will jump the price up so high, I personally would be a target in this high price war we have going around here. Im adament I dont want that!!!! It has to remain cheap and will, or i wont make it! I want everyone to be able to use it. Im shooting for $20 or less.
 
Also it has to remain simple. So far, the decoder is turning out to be more complex than the device im hooking it too lol. Adding electronics to this i just know would triple the price before it gets off the drawing board. This whole post was just to find a DCC circuit that would control this device. Im at the stage of testing this, this way. Last stage, put it in a model. So im not that far away from making it work. The theory worked under analog conditions, the decoder is now holding me back.
 
Let me ponder on it some more. Maybe I can come up with another way of performing the same 'action' the 2 pulses were designed to do. I may just hit you up with some more technical questions if you dont mind. Your info so far has been exceedingly beneficial. Keep your fingers crossed, maybe i will have another stroke of genius. Or just the stroke. Who knows at this point.
 
Maybe i should invent remote HO couplers, seems to be easier than this is turning out to be, huh? Thanks Randy!
 
PM Railfan
 
 
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Posted by PM Railfan on Thursday, November 20, 2014 8:10 PM

hornblower

Okay, fair enough.  But I was thinking that it might be easier to redesign your "device" to operate on a few milliamps rather than try to find a decoder with a 1 amp function output.  That way, any current decoder could be used.  

Since you don't want to expose your device to the model railroading world yet, it might be better to look for answers on another electronics related forum.  You could also copyright your idea so that nobody can steal it from you.  A very easy way to do that is to enclose the "device" description and any plan sketches in an envelope and then mail the envelope to yourself.  The postmark will officially define when the idea was originated and all you have to do is file the unopened envelope for future legal use should it ever be required.

 
In truth, no amps are needed. Its the voltage here that is the ticket. I said 1amp because all decoders have some amount of amps (either milli amps or higher) and i wanted to find a decoder like that. By stating 1amp max., I figured I would be in the 'average' range of todays typical decoders.
 
My appologies to you and the forum, im not that great at expressing ideas - im not a technical writer. I know Im being somewhat evasive as you said, sorry, but i have to. That coupled with my bad tech writing im sure is giving yall fits. Especially Randy.
 
I chose the forum for its direct relationship and experience with DCC. Most normal electronics forums dont even know DCC exists, and wouldnt take the time to talk to someone who 'plays with trains'. Besides, I trust you folks more than i would those folks. I am versed enough in electronics (plus im already a computer programmer) to make a decoder circuit. Im hoping to avoid this as I want the 'device' to be simple and CHEAP! However, it has to mate with todays existing decoders. So i have to make it work with those, not mine.
 
Copyrighting is fine, and I know the postal trick. However I use a PDS which 'in my opinion' is way more binding (and I already have one pending should this work). Should I succeed, I hope I could get a patent. Thanks for posting the info though, im sure there are those that dont know about the Postal Copyright which IS a great idea.
 
PM Railfan
 
(id put an electrical schematic up if i could which would make this soooo easy, but MR doesnt host pictures and im not about to use a third world photo hosting site)
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Posted by rrinker on Thursday, November 20, 2014 8:00 PM

 Plus keep detailed records including dates of everything you design, then when you apply for a patent it won;t matter that someone else built something similar, as long as you have unrefutable proof that your design predates theirs.

 The 2 size pulses are still a problem even if the circuit draws milliamps instead of amps. No one's decoders really do that. Hence the interface circuit. Which could also have a rectifier and filter to get 1 amp+ in DC from the track, if needed.

                    --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by hornblower on Thursday, November 20, 2014 7:40 PM

Okay, fair enough.  But I was thinking that it might be easier to redesign your "device" to operate on a few milliamps rather than try to find a decoder with a 1 amp function output.  That way, any current decoder could be used.  

Since you don't want to expose your device to the model railroading world yet, it might be better to look for answers on another electronics related forum.  You could also copyright your idea so that nobody can steal it from you.  A very easy way to do that is to enclose the "device" description and any plan sketches in an envelope and then mail the envelope to yourself.  The postmark will officially define when the idea was originated and all you have to do is file the unopened envelope for future legal use should it ever be required.

Hornblower

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Posted by PM Railfan on Thursday, November 20, 2014 7:29 PM

rrinker

Well, the solid state interface circuit I describe would be small, and could be driven from the tiniest of decoders, so it wouldn;t really take up all that much room.

 There are some DIY decoder projects, they tends to use PIC or Aurdino processors so it wouldn;t be too hard to modify the function control to produce the needed 3 and 5 second pulses, plus just add an extra level or transistors to the function controls that can handle the higher current and you should be good to go. That of course means your device would have to come witht he decoder. Using my interface circuit idea, you could ship it with a standard 9 pin plug and the end user could supply whatever decoder they wanted.

                         --Randy

 
DIY decoders aye? Hope you wont be upset that I had that idea already. I decided not to go that route because i am trying my best to follow the addage -KISS.
 
Im truly hoping to send just this product sans decoder and just plug it in to an existing one on a model (universal). I want it so easy peasy that any newbie could plug it in. From what i gather from you and others, the decoder i am specifically looking for doesnt exist in todays current decoders (the exact way i want it).
 
I may have to relent and just sacrifice a decoder to get me past this next step, or do as you suggest and use a DIY. Next time just lie to me and say "the one you want is made by ACME, part number: BRY-549 (for those that remember warner bros. and hee haw!)Laugh
 
Randy, I thank you very much for your input on this! Big help!!!
 
PM Railfan
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Posted by rrinker on Thursday, November 20, 2014 6:45 PM

Well, the solid state interface circuit I describe would be small, and could be driven from the tiniest of decoders, so it wouldn;t really take up all that much room.

 There are some DIY decoder projects, they tends to use PIC or Aurdino processors so it wouldn;t be too hard to modify the function control to produce the needed 3 and 5 second pulses, plus just add an extra level or transistors to the function controls that can handle the higher current and you should be good to go. That of course means your device would have to come witht he decoder. Using my interface circuit idea, you could ship it with a standard 9 pin plug and the end user could supply whatever decoder they wanted.

                         --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by PM Railfan on Thursday, November 20, 2014 6:20 PM

rrinker

 Nobody makes such a thing, at least not as a mobile decoder. If a relay can't work, a decoder can;t either - all it is is a solid state switch connecting a wire to ground, same as a relay contact would do.

 How I would approach this would be to use a 4 function function only decoder, like a TCS FL4, and design a simple interface circuit. Function 1 fromt he decoder would trip 12V Output 1 for 3 seconds, Function 2 would trip 12V Output 1 for 5 seconds, and functions 3 and 4 would do the same for 12V output 2.

 If this is for something large, I checked and found one large scale decoder that can handle more than 500ma per function - the Digitrax DG583S. Each function wire (well, it has screw terminals) can handle 2 amps, with a maximum load not to exceed 5 amps. What you can;t do is get those 3 and 5 second bursts. And, liiike any other decoder, the 'switch' of the function connects the line to ground - everyone is in the habit of calling them outputs but they are not outputs, they are current sinks. The function common wire, the blue, is +12V give or take depending on track voltage. Each of the function connections is a SINK to ground, not a source.

 The independent part is true of any decoder. Any given function connection can be independent of any others, such that the F1 button would turn on one nad only one wire, and F2 would turn on a different wire, and so on. They CAN be linked by programming, but can be independent. Also, since each one is a current sink, you can physically connect 2 wires to the same device with no harm. So you could tie two wires to the device and program one of them for a 3 second burst and one for a 5 second burst, if the decoder could do that. But I haven't found oen that can do this. TCS might, there are a lot of options co configure flashing light effects, but then you don;t have the full amp capability and will need a drive in between, either a relay or a solid state relay. Again, no matter what your device is, if it can be triggered by a pulse of power from the decoder, it can be triggered with a relay in the circuit - it HAS to.

 No decoder provides pulses of power - the function lines are all connections to ground,. The blue wire on a standard decoder is +12 give or take, always live.

                    --Randy

I didnt think it existed but I had to ask you folks none the less. I could use a relay if i wanted but it is so unneeded (and takes just that much more space). As much as I have heard and seen about DCC this just cant be hard to do.

Your post however is dog gone good one towards advancing my project. Thank you for your time Randy and info. It helps tremendously.

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Posted by PM Railfan on Thursday, November 20, 2014 6:16 PM

hornblower

Maybe if you'd quit making such cryptic inquiries and tell us what the heck your "device" is and how you want to use it, we might be able to answer your questions with solid answers.  I highly doubt your "device" is so unique to the modeling world that you have to keep it a secret.

It doesnt exist yet in model railroading. Would you give away your secrets before you knew if they worked in actual usage? Not trying to be elusive but i think im onto something great here. Id like to have something to put on my headstone that is uniquely mine.

Testing of the theory worked, now I need to make the actual 'object'. To do that, i need a DCC decoder. A particular one. I have no DCC so i figured before i waste money Id ask the forum. R&D you might say.

Dont worry, if it works, I wont have any problem telling EVERYONE! Thats who im making it for.

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Posted by hornblower on Thursday, November 20, 2014 6:11 PM

Maybe if you'd quit making such cryptic inquiries and tell us what the heck your "device" is and how you want to use it, we might be able to answer your questions with solid answers.  I highly doubt your "device" is so unique to the modeling world that you have to keep it a secret.

Hornblower

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Posted by rrinker on Thursday, November 20, 2014 6:10 PM

 Nobody makes such a thing, at least not as a mobile decoder. If a relay can't work, a decoder can;t either - all it is is a solid state switch connecting a wire to ground, same as a relay contact would do.

 How I would approach this would be to use a 4 function function only decoder, like a TCS FL4, and design a simple interface circuit. Function 1 fromt he decoder would trip 12V Output 1 for 3 seconds, Function 2 would trip 12V Output 1 for 5 seconds, and functions 3 and 4 would do the same for 12V output 2.

 If this is for something large, I checked and found one large scale decoder that can handle more than 500ma per function - the Digitrax DG583S. Each function wire (well, it has screw terminals) can handle 2 amps, with a maximum load not to exceed 5 amps. What you can;t do is get those 3 and 5 second bursts. And, liiike any other decoder, the 'switch' of the function connects the line to ground - everyone is in the habit of calling them outputs but they are not outputs, they are current sinks. The function common wire, the blue, is +12V give or take depending on track voltage. Each of the function connections is a SINK to ground, not a source.

 The independent part is true of any decoder. Any given function connection can be independent of any others, such that the F1 button would turn on one nad only one wire, and F2 would turn on a different wire, and so on. They CAN be linked by programming, but can be independent. Also, since each one is a current sink, you can physically connect 2 wires to the same device with no harm. So you could tie two wires to the device and program one of them for a 3 second burst and one for a 5 second burst, if the decoder could do that. But I haven't found oen that can do this. TCS might, there are a lot of options co configure flashing light effects, but then you don;t have the full amp capability and will need a drive in between, either a relay or a solid state relay. Again, no matter what your device is, if it can be triggered by a pulse of power from the decoder, it can be triggered with a relay in the circuit - it HAS to.

 No decoder provides pulses of power - the function lines are all connections to ground,. The blue wire on a standard decoder is +12 give or take, always live.

                    --Randy

                             


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by PM Railfan on Thursday, November 20, 2014 6:09 PM

farrellaa
 
PM Railfan
 
maxman

Sounds to me like he is asking about an accessory decoder, and possibly wants it to do something other than operate a locomotive.

But, I could be wrong.

 

 

 

Your not wrong, yet very warm. I want to be able to use my device on both cars AND locos, so it wouldnt be an accessery decoder. I am however driving accessories with it. Which is why your warm.

 

 

 

 

OK, how about remote couplers? (:}

 

MMMMM wouldnt that be nice huh! Loose lips sink ships is all im gonna say! Zip it! Besides, if it was remote couplers, Kadee would have done that already.

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Posted by farrellaa on Thursday, November 20, 2014 6:02 PM

PM Railfan
 
maxman

Sounds to me like he is asking about an accessory decoder, and possibly wants it to do something other than operate a locomotive.

But, I could be wrong.

 

 

 

Your not wrong, yet very warm. I want to be able to use my device on both cars AND locos, so it wouldnt be an accessery decoder. I am however driving accessories with it. Which is why your warm.

 

 

OK, how about remote couplers? (:}

Life is what happens while you are making other plans!

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Posted by PM Railfan on Thursday, November 20, 2014 5:54 PM

maxman

Sounds to me like he is asking about an accessory decoder, and possibly wants it to do something other than operate a locomotive.

But, I could be wrong.

 

Your not wrong, yet very warm. I want to be able to use my device on both cars AND locos, so it wouldnt be an accessery decoder. I am however driving accessories with it. Which is why your warm.

 

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Posted by PM Railfan on Thursday, November 20, 2014 5:28 PM

Thank You's to those who've answered so far. Please accept my appologies for not being more precise. My exact desire is:

If there are 3 types of decoders (as listed above), I need 'any' of them as long as they have all the channels they normally do, PLUS one front aux channel, and one rear one.

For each aux channel i need 12vdc @ 1a max. sustainable at either 3 second or 5 second spans which should be selected by the controller (either 3 or 5 sec burst, user chooses). I need each of these two auxillery channels to work independantly of every other channel on the decoder, including each other.

All i need to know is who makes it, and its part number.... if it even exists. I can use any of the 3 types, it makes no difference. It just have to have the two extra channels rated at the above specs. and programmability.

I cant say what its for (yet!), But can tell you it is not for smoke, sound, lights, motor, or any other existing channel if this helps. This is something totally new. And no, I cannot use a relay on this, its not that kind of circuit. I dont need amps as much as voltage. 1amp should do it. Gotta have 12 volts though. Its is just a simple, selectable channel that operates something low powered.

Thanks one and all for your efforts!

Cheers!

PM Railfan

 

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Posted by richg1998 on Thursday, November 20, 2014 5:13 PM

If what you are operating needs more current that a function output on a decoder can supply, go with a relay. Some use a light/function output and a relay with a reverse diode on the coil to operate a smoke unit which is usually over a hundred MA.

Look in the below link.

http://cs.trains.com/mrr/f/744/t/227167.aspx

Edit.

The usual method to have the link active is NOT working again. Man, theses techies are so bad on the latest upgrade. Need to get some cheese for my whine. lol

Rich

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Posted by maxman on Thursday, November 20, 2014 4:55 PM

Sounds to me like he is asking about an accessory decoder, and possibly wants it to do something other than operate a locomotive.

But, I could be wrong.

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Posted by jrbernier on Thursday, November 20, 2014 4:20 PM

  Most decoders fall into three basic catagories:

Motor Function(and most include both forward/reverse lights).  Some may have up to 6 'function' outputs on them.  Read the manuals; the function outputs usually supply 12 volts DC at no more that 1/8th of an amp.

Light Function Only - Usually has multiple function outputs.

Sound/Motor Function - Usually have several function outputs(some are sound only).

Jim

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Posted by blabride on Thursday, November 20, 2014 3:16 PM

Also check out Train Control Systems website they have a very good manual with some of the easiest explanations I have seen on programming functions to do what you need them to do. They also make an inexpensive function only decoder that easy to use and wire up.

Steve B

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Posted by NP2626 on Thursday, November 20, 2014 8:26 AM

Decoders can have many functions, bell, couple/uncouple sound, horn/whistle, lights on/off.  Digitrax (the manufacture I use) has a very detailed website discussing anything and everything about DCC.  Possibly you could learn about functions (Channels) at their website.  My guess is that all DCC manufacturers have very in depth websites to help sell their products.

NP 2626 "Northern Pacific, really terrific"

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Posted by rrinker on Thursday, November 20, 2014 7:56 AM

 Not sure what you are asking. There aren't "channels" in a decoder. You have motor only decoders, which have motor control, and 2 or more function controls for lights (and other things - you can control anything within the current rating of the function, or for something that draws a higher load, like a smoke unit, you can control a relay with the decoder function that in turn controls the smoke unit). Then you have motor and sound decoders, which have motor control, 2 or more functions for lights, plus a multi-channel audio system that can play 3 or more simultaneous sounds. Some brands of sound decoders allow you to replace the provided sounds with your own recorded bits - even make the train play Jingle Bells if you want. And there are some decoders that are sound-only - they have the light outputs, and the sound stuff, but lack the motor control.

I don't know of any that have something else besides motor, sounds, and the lights. Do you mean like a second motor drive?

                       --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Quick answers for DCC Decoders (has been answered). "Working coupler" thread now seperate.
Posted by PM Railfan on Thursday, November 20, 2014 7:31 AM

EDITED (2/2/2015): This is the original post which has now been answered. To follow the working HO coupler project, please go to the new thread....

http://cs.trains.com/mrr/f/744/t/244165.aspx

OP - PM Railfan

 

ORIGINAL POST:

Good morning folks! Im working on a project that I could use the help of fellow modellers. I do not run DCC, i still use ADC. So I need to find out just some quick basic info from you folks who have, and use DCC. Specifically the decoder.

I do understand how they work and the principles. I need to know, of all the manufacturers of decoders, who makes a decoder (if it is made) with the following specs....

Decoders obviously have a motor control channel, light control channel, and more than likely a sound control channel. Is there a decoder with an auxillery channel? A channel that a modeller can use for 'other' purposes than the normal channels above.

Checking current publications give general references on how to wire them, but none ever show an auxillery circuit. Diagrams are also generally basic  so they cover 'most' of the popular decoders. No details.

Im thinking someone who really gets into the nitty gritty with decoders could help with this project as researching each company out there for this one type of decoder could take months.

Company name, decoder part number would be what i am after. Any help is definately appreciated!

 

Cheers!

PM Railfan

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