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[mcjaco]

sounds like a story that needs to be shared

What happens in Modutrak. Stays in Modutrak.


 

[skytop35]

sounds like a story that needs to be shared

The short story is all the smoke was let out of a block detector. It did leave a black mark under the module though.

[mmagliaro]

I have a handy DIY photocell detector circuit that I like to use for things like this.  It's very nice for switching small relays in reaction to a photocell being covered by a train.  I particularly like it because it is very tolerant of low light situations and triggers the load from full off to full on at a very sharp transition point in the light level ( the photocell at 22k ohms has the load fully off and at 33k ohms, the load is fully on. )
6 components on a little scrap of solder perf board and you're good to go.  Cheap, effective, and it can drive a small relay directly.   (Yes... since this is an all-DC approach, why not go whole-hog and make your own detectors out of discrete transistor circuits!)

[Sokramiketes]

IIRC, the B'mann reverser kills the power at the end of each cyle to "park" the train for a moment, so this could be problematic.

In thinking through implementation of typical DC practice (flipping polarity of the entire mainline between loops) and the DCC approach of flipping the end loops themselves, I started to wonder if I needed continuous unimpeded running.  If I have a couple staging sidings in each loop, with the eventual goal of cycling trains to match the scheduled parade of trains on the Columbia River Sub, then pausing a train, or actually parking it in the loop, as polarity is adjusted, isn't really an issue.  I like the idea of flipping stuff only on the loops and leaving the rest of what could be a long layout untouched. 

If speed ramping up and down could be accomplished within the staging tracks via circuits, then cascading tortoises could handle most of the "logic". 

Maybe it's the rolling ball track of exhibition layout operation.  And with that, am I happy animating the layout versus operating it.  Probably, given that it's Z scale and I'm modeling an area with little operational interest in terms of switching puzzles or other nonsense. 

[Sokramiketes]

I have a handy DIY photocell detector circuit that I like to use for things like this.  It's very nice for switching small relays in reaction to a photocell being covered by a train.  I particularly like it because it is very tolerant of low light situations and triggers the load from full off to full on at a very sharp transition point in the light level ( the photocell at 22k ohms has the load fully off and at 33k ohms, the load is fully on. )
6 components on a little scrap of solder perf board and you're good to go.  Cheap, effective, and it can drive a small relay directly.   (Yes... since this is an all-DC approach, why not go whole-hog and make your own detectors out of discrete transistor circuits!)

This sounds useful!

[mmagliaro]

This sounds useful!

Well, here ya go, then!

All this stuff is really cheap.  You can buy a whole bag of 2N3904 transistors for a buck or two,  and photocells show up all the time on eBay or electronics surplus websites.  The hardest part is finding a small one that will fit down between the rails in N Scale.  Here's one that should work well, and these cost about a dollar:
https://www.adafruit.com/product/161
The rest is just resistors, diodes and a little trimmer pot.  You may already have everything in your electronics junks box for this.

I use a relay very similar to this one (and these are selling 5 for $12)
https://www.ebay.com/itm/5-x-12V-Miniature-Latching-Relay-DPDT-HFD2-/253282311457?_trksid=p2349526.m4383.l4275.c10

Here's one at Mouser for $2.19 a piece that looks perfect:
https://www.mouser.com/ProductDetail/KEMET-NEC-Tokin/EC2-12TNU/?qs=sGAEpiMZZMs3UE%252bXNiFaVLHF5q190qnti8dAigMw31Y%3d


I use DIP relays that can handle 2 amps, and they have 400 ohm coils, hence the indication of "RLoad" being 400 ohms in the circuit below.   If you start trying to switch other types of relays, check the coil current to be sure a small 2N3904 transistor can handle it.   Another important point is that with a 400 ohm coil, the relay coil can be energized indefinitely without draining much current or getting hot (much like a Tortoise switch motor), which is important because when the photocell in this circuit is covered, this circuit will energize the relay continuously - so don't use one with a low-ohm coil like a switch machine that will fry if you leave it on all the time.

Other important notes on using this for reverse loop behavior:
1   I use a LATCHING relay for this, so that as soon as the photocell is covered, the relay switches, and it will STAY there, even if you have bad luck and some light sneaks between the cars of the train and lets the photocell go hi/low/hi, etc.   

2.  When the reverse detector at the other end of the layout is covered, it will energize the relay the other way.  I use dual-coil relays, which makes this really easy.  Each detector is hooked to one of the two, separate coils on the relay, so they can fire it one way and then they other without getting in each other's way.

UNLESS....

3.  If both detectors were to be covered at the same time, this would make for a very unpleasant situation.
The two reverse loops would be trying to simultaneously change the relays and track polarity to go opposite ways at the same time.  Using the DIP relays I use, all that would happen is that both coils would be energized, and the relay may or may not move to a position that is impossible to determine.  Nothing would blow up, but it wouldn't do anything useful, either.

[Sokramiketes]

Thanks, Max.  That should be useful. 

[Ed Kapuscinski]

I have nothing to add, other than loving this thread.

I love the idea of choosing solutions that are appropriate for the requirements as opposed to using a hammer on a screw.

[Dave V]

Admittedly I'm sticking with Digitrax primarily because it's what I have, but I can sympathize with the frustrations of both decoders and command stations getting "scrambled brain" and turning what should be a very simple action (running a train) into an agonizing duel of the fates.

I lose patience with folks who claim one size fits all...or that their way is the only way.  DC makes sense for certain applications.  My CMRy, for example...I'm running DC.  But DCC works for my Pennsy and I plan to use it on the RGS to unleash the full potential of the Soundtraxx decoders in my Blackstone engines.  Each application is different and has different requirements.

That so many really good modelers here have had reason to eschew DCC is proof enough to me that it is not the panacea some make it out to be.

[Tom L]

I'm a analog person in a digital world .......

[ Guests cannot view attachments ]

Tom L
Wellington CO

[Nick Lorusso]

Mike I'd recommend trying to contact guys from the BAZ Boys on Trainboard in the Z-scale section for help. I'd personally go with DCC set at 9Vs and NCE.

[DKS]

I love the idea of choosing solutions that are appropriate for the requirements as opposed to using a hammer on a screw.

That so many really good modelers here have had reason to eschew DCC is proof enough to me that it is not the panacea some make it out to be.

This and this. I've worked with DCC enough to realize it offers no benefits for me--even just the opposite: it creates unnecessary frustration. The (somewhat) greater complexity of DC wiring is more than overshadowed by the complexity of installing, programming, using and debugging DCC. I've faced a lot of backlash from DCC fans for many years, accused of being a Luddite, a dinosaur, and even holding back progress (seriously?). They totally overlook the fact that I have nothing against the technology, and in fact have promoted it for those who will benefit most from it. There's no reason to use it just because everyone else does; it's not a one-size-fits-all solution. So I applaud anyone who wants to use it because they recognize it as a better approach for their application.

The latest fad of making trains controllable though smartphones is a real turn-off to me. Just consider how often smartphones are upgraded or rendered obsolete over the years and what that might do to one's established operating protocols.

And especially this. It'll be a long time before toggles switches become obsolete.
 

[Loren Perry]

There is no shame in admitting to being a DC person today. I'm one myself. My "Hollywood Railroad" runs reliably and easily every time I power it up. Every locomotive comes to life when commanded to do so. True, I don't engage in complex operations or lashing up locomotives of differing manufacture, but for my purposes, DC is just fine and it's far more economical than converting everything to DCC. Maintenance is easier, too. So is troubleshooting.

Model railroading seems to be made up of a combination of modelers and gadgeteers. A fortunate few are good at both. But most seem to be good at just one or the other. For example, I see lots of photos of layouts that are heavily involved in DCC complete with functioning signal systems but would otherwise be classified as "Plywood Centrals" because the builders have little time left over to actually create a "model" railroad. I was once a gadgeteer but am now more of a modeler. I guess I got tired of trying to figure out something that needed an instruction manual and electronic support equipment to make operate properly. I'm 70 years old now, and those days are behind me.

I used to build eight-channel Heathkit R/C systems (successfully) and scratch built large scale model warships with multiple functioning weapons and sensor systems plus sound effects and other onboard gee-whiz complexity. I also built and successfully flew scale multi-engine model aircraft with retractable landing gear, flaps, and landing lights. So I can do this. I just choose not to on my model railroad.

My layout is for pleasure and relaxation. Trying to make a DCC system work and keeping it working with multiple locomotives and elaborate trackwork takes away from that pleasure. It's also expensive when one adds up the cost of base units, boosters, decoders, hand-held throttles, and all the related hardware. Not to mention replacing occasional burned-out decoders. As for sound effects - if I want to hear the sounds of a locomotive, I have a collection of CD's to pick from. When operating my railroad, I have music from the 1950's playing softly in the background to set the mood.

The latest fad of making trains controllable though smartphones is a real turn-off to me. Just consider how often smartphones are upgraded or rendered obsolete over the years and what that might do to one's established operating protocols.

So to all you analog/DC-types out there - you're not alone, not by a long shot. Even MRC's latest ads are reflecting the continuing popularity of DC controls with their new products geared toward model railroaders like us.

I'm a analog person in a digital world .......

(Attachment Link)

Tom L
Wellington CO

[DKS]

In thinking through implementation of typical DC practice (flipping polarity of the entire mainline between loops) and the DCC approach of flipping the end loops themselves, I started to wonder if I needed continuous unimpeded running.  If I have a couple staging sidings in each loop, with the eventual goal of cycling trains to match the scheduled parade of trains on the Columbia River Sub, then pausing a train, or actually parking it in the loop, as polarity is adjusted, isn't really an issue.  I like the idea of flipping stuff only on the loops and leaving the rest of what could be a long layout untouched. 

If speed ramping up and down could be accomplished within the staging tracks via circuits, then cascading tortoises could handle most of the "logic". 

Maybe it's the rolling ball track of exhibition layout operation.  And with that, am I happy animating the layout versus operating it.  Probably, given that it's Z scale and I'm modeling an area with little operational interest in terms of switching puzzles or other nonsense.

This is exactly how the staging yard on Rick Spano's S&U functions. I built it for him decades ago, and it still works today, even accommodating his switch from DC to DCC. If you're seriously thinking of taking this route, I'm happy to offer up some ideas.
 

[strummer]

I'm afraid I fall into this group as well. I just don't feel the need to "start over", so to speak; plus, I have a wonderful Heathkit RP 1065, which runs my stuff beautifully (right, Max? )

It seems that, for the most part anyway, many of the issues with these beautiful new locos is often tied in with the "bells and whistles" that are part of the DCC landscape. This is true in many scales (just go to one of the Lionel forums, and you'll see what I mean.) It's one of the reasons why I cling to sites like eBay, to purchase older items. I pretty much know what I'm getting and what to expect when it arrives. I haven't enough confidence (or experience) to tackle those little circuit boards, etc.

I have nothing against any of the new stuff; it just isn't for me. Plus, I'm old and set in my ways! 

Mark in Oregon