I was cruising the web and came across some British modelers who real hobby is electronics in connection to model railroading. One says that in theory you could hook up a decoder to the track instead of an engine, now this would be for the person that still runs DC and you would loose all the neat things about DCC except for running trains. Now he said the only thing to work out was if a short would occur but said that should not be a problem. Now what do you think about this?????????? Doable????????? By the way, you can get an 8amp decoder with 30 amp max load rating.
If all you are trying to accomplish is a walk-around throttle capability on a DC layout, I suppose it would work. Need to add circuit breaker or current limiter (light bulb) between decoder and track.
You'd still just have a DC layout, with all the operational limitations therein, but at most of the cost of a DCC system (one big decoder instead of smaller ones in each loco).
Andy
Back when the smallest decoders were just barely able to fit in a heavily cut up N Scale engine, the Z scale guys were doing this. Works great for one train. If each block had its own decoder and address what would be the result if a train crossed block boundaries? Could never get that answered. I suspect the decoder(s) would be trashed as I've trashed a couple of decoders by feeding DC into the grey and orange motor drives. Anyone want to test?
Martin Myers
The reason I ask is I currently run a train engineer setup but have been having trouble finding backup parts, just in case. Works great for a lone wolf with a giant dogbone with two yards that are isolated. Also I run some small stuff like MDC critters!
We won the war with the British way back when to gain our independence. Why go backwards now?
Elmer.
The above is my opinion, from an active and experienced Model Railroader in N scale and HO since 1961.
(Modeling Freelance, Eastern US, HO scale, in 1962, with NCE DCC for locomotive control and a stand alone LocoNet for block detection and signals.) http://waynes-trains.com/ at home, and N scale at the Club.
gandydancer19 We won the war with the British way back when to gain our independence. Why go backwards now?
rrebellNow he said the only thing to work out was if a short would occur but said that should not be a problem.
A short would indeed be a problem, since the booster would not see it. And the question is not "if" a short will occur, but when.
rrebellBy the way, you can get an 8amp decoder with 30 amp max load rating.
8 amps cooking away somewhere on your layout with no circuit breaker protection after an un-noticed short seems like a very bad idea.
Layout Design GalleryLayout Design Special Interest Group
Fiqured a fuse or two, have a bunch of posi-fuses I could use.
rrebellFiqured a fuse or two, have a bunch of posi-fuses I could use.
Possibly not quick enough to avoid fried equipment. Using stuff in ways for which it was not designed seems like a poor choice -- but it's your gear and your house.
Why not just use an MRC power pack instead of an expensive DCC system and decoder ? But if you really think this is a good idea, get a decoder intended for G-scale use.
You can get fast acting fuses, they use car fuses, I was only thinking of protecting the decoder, the equipment should be fine. I have heard talk of damaged stuff in HO but have never seen it, even at large clubs! Could it be an urban myth? I have found many of those since starting my layout!!!!!
rrebellI have heard talk of damaged stuff in HO but have never seen it, even at large clubs!
I've personally seen plenty of stuff fried, especially when the layout didn't have sufficiently robust wiring to let the booster detect a short. A user on the forum ("Cudaken") burned up many pieces of equipment in the beginning due to poor wiring and other mishaps when he was getting started.
8 amps across the rails and through an engine (as in a short in the set up you were talking about) can create trouble pretty quickly.
But hey, if you think it can't happen to you, do whatever you like.
Carry on.
There are a few pictures on one of the Yahoo DCC groups showing what happens when 8 amps runs through a derailed loco truck.
And despite an 8 amp continuous/30 amp surge rating in those G scale decoders, they still can't take a dead short for any period of time. Even though with overload protection - it's designed to keep the decoder from frying if you run more than 8 amps continuous through it, but it doesn't cut out quickly enough to prevent damage in the event of a dead short. Even some smaller decoders have short detection, where they will flash the lights if the motor leads are shorted, but even that is expecting a gradual start-up = if you are already at 3/4 throttle then suddenly short the output - poof!
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Storys like this make me wonder at times about the longevity of DCC!!!!!!!!!!!!!!!!!!!
In what way?
Hooking up a decoder to the track so it acts like a regular power pack supplying power to the rails strikes me as a very exepensive way to simply get a decent DC power pack. Full DCC system, plus the heavy duty decoder PLUS you'd still have to do all the DC wiring, such as cab control, PCC, or MZL AND still have to worry about thw whole short issue - vs just buying a good transistor power pack if you aren;t ready for DCC. It all strikes me as just a foolish engineering exercise.
MAYBE is you had an otherwise DCC layout and had say a trolley loop through the town and didn;t want to put decoders in the trolleys - although given that a friend of mine HAS decoders N SCALE 4-wheel Birney cars... so you could connect a decode to the rails and run the plain DC trolley that way. For a whole layout though - it buys you exactly nothing but money spent and a potential for disaster if a loco derails.
This comes under the subject heading off, if you don't know what you are doing, don't do it.
From what I can see, They Say and I Heard did not give you any specifics with diagrams.
Rich
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
rrebell I was cruising the web and came across some British modelers who real hobby is electronics in connection to model railroading. One says that in theory you could hook up a decoder to the track instead of an engine,....Now he said the only thing to work out was if a short would occur but said that should not be a problem....
I was cruising the web and came across some British modelers who real hobby is electronics in connection to model railroading. One says that in theory you could hook up a decoder to the track instead of an engine,....Now he said the only thing to work out was if a short would occur but said that should not be a problem....
I have said on more than one occasion that a decoder could be wired to the track as a rather expensive way to get a pulse width modulation DC throttle. I used the illustration to point out that a decoder is functionally nothing more than a miniature DC throttle with a digital control link that can be installed in the locomotive. The output to the motor is the same from a decoder as from a DC PWM throttle.
But as others have said....why would you want to do this? Aristo makes a very nice radio-controlled DC PWM throttle, if that's what you want. There are also plenty of designs and commercial DC throttles - some with PWM, some with other forms of pulse - that will give you similar results in smooth running to a decoder throttle. Decoders and DCC systems are designed to handle short circuits on the track side of the decoder, not the motor side. DC throttles assume short circuits will happen across the output, decoders do not. And for a DCC decoder, you will need a DCC system to control the decoder. DC throttles generally have a much simpler (and less expensive) throttle control.
my thoughts, your choices
Fred W
rrinker In what way? Hooking up a decoder to the track so it acts like a regular power pack supplying power to the rails strikes me as a very exepensive way to simply get a decent DC power pack. Full DCC system, plus the heavy duty decoder PLUS you'd still have to do all the DC wiring, such as cab control, PCC, or MZL AND still have to worry about thw whole short issue - vs just buying a good transistor power pack if you aren;t ready for DCC. It all strikes me as just a foolish engineering exercise. MAYBE is you had an otherwise DCC layout and had say a trolley loop through the town and didn;t want to put decoders in the trolleys - although given that a friend of mine HAS decoders N SCALE 4-wheel Birney cars... so you could connect a decode to the rails and run the plain DC trolley that way. For a whole layout though - it buys you exactly nothing but money spent and a potential for disaster if a loco derails. --Randy
Aristo is slowly getting out of the buisness!!!!!!!!!
Well, I have been doing some research. Seems I have not kept up with the new technology like I thought I was (so many inventors out there now and building on one another thanks to the Internet).there have been a few breakthroughs that I was not aware of that makes battery powered Ho possible, in fact later this year one is being released to the general public that is DCC controlled and a radio controlled one is right behind it. The new battery's (these systems work on battery's out now) are about two years out but have twice the power, half the weight and of comparable cost.
deleted
We've used sound decoders in a similar way where they are hooked up to our preamp for a large under table sound system. Then MU'd to a loco.
Richard
That's quite a bit different sinc ethe motor outputs aren;t being used on those sound decdoers. Hooking the speaker outputs to a preamp to drive BIG speakers is no danger at all to the decoder, and you get to hear the full quality of the sound as opposed to pushing it through tiny onboard speakers.
Randy,
It does sound Awesome--4' speakers. BTW, don't forget to bridge the motor outputs with a resistor. Synching the motor isn't that tough with JMRI.
cuyama rrebellFiqured a fuse or two, have a bunch of posi-fuses I could use. Possibly not quick enough to avoid fried equipment. Using stuff in ways for which it was not designed seems like a poor choice -- but it's your gear and your house.
Reminds me of an old technician's saying. It went something like this: The purpose of the electronics is to protect the fuse.
..... Bob
Beam me up, Scotty, there's no intelligent life down here. (Captain Kirk)
I reject your reality and substitute my own. (Adam Savage)
Resistance is not futile--it is voltage divided by current.
There are quick acting fuses and slow and time delay and --------.