@shorling posted:

I can report that I use hundreds of Town and Country Lionel direct replacement LED bulbs on my layout.  These LED bulbs have been on my layout for over 10 years with zero failures.

I'm pretty sure the wedge-base LED bulb (with internal diode and resistor) was from Town and Country.  Additionally the T&C site had this review comment of the bayonet LED green bulb:

@Steve24944 posted:

The other contacts on the relay can be used to kill the power to the center rail in the block approaching the signal,  ( not shown in my drawing )  so the following train stops at the red signal, but will proceed when signal turns green.

Killing power to the tracks works for conventional running, but not for command.  Killing power to the tracks for command locomotives doesn't accomplish the goal you mention as TMCC/Legacy locomotives will simply stop and wait to be started again from the remote, DCS locomotives will pause briefly and then shutdown and you'll have to do the startup sequence from the remote to get them moving again.

I have modified my drawing to show how relay can be used to stop a following train.  When relay is open and signal is green, power flows to the center rail of track approaching green signal.  When Relay is closed, power is cut to the center rail, stopping train, until previous train clears the insulated rail block.  Again, I am showing only one track length,the insulated rails, outside rail to control relay, and insulated center rail to stop following train can be longer.

I can't speak to how this would effect command control or other modern control systems.  I am a Post War, conventional operator.

Steve

It actually was Stan, I should have posted a clip of the post I was responding to, I edited my reply.

@Steve24944 posted:

I have modified my drawing to show how relay can be used to stop a following train.  When relay is open and signal is green, power flows to the center rail of track approaching green signal.  When Relay is closed, power is cut to the center rail, stopping train, until previous train clears the insulated rail block.

It's a your-mileage-may-vary, but if you like threading-the-needle there have been accounts where you apply some lower (non-zero) track voltage to center-rail to stop a train (rather than completely removing power).  This is enough voltage to keep the electronics alive (e.g., sounds, lights) ... but not enough to move the engine.   Yes, the engine is stalled and some may consider this untoward but it is arguably a viable work-around.

If you use MTH PS2/PS3 in conventional, a track voltage of around 8V will stop the engine without stalling the motor and the electronics stays alive.  In command, a track voltage of around 8V should also stop the engine from motor stall but the electronics should stay alive.  Again, one is entitled to their opinion on whether this is any way to run a railroad...but then again this is a discussion forum...

One issue with at least the TMCC stuff I tried the reduced power trick with was the variability between locomotives.  Some locomotives would stop just as intended and then move out when higher voltage was restored.  However, others would not stop, primarily lightweight stuff that didn't take much energy to move.  By the time you got the voltage where they would stop, you were having issue with the electronics loosing it's marbles until a power cycle.

@stan2004 posted:

I'm pretty sure the wedge-base LED bulb (with internal diode and resistor) was from Town and Country.  Additionally the T&C site had this review comment of the bayonet LED green bulb:

Autoillumination also has a selection of direct replacement LEDs.  They offer more bulb colors and temperature colors but are pricy.   They also have 14 VAC LED bulbs.  A cheaper solution to warm color temperature can be to spray the bulb with translucent paint.

@stan2004 posted:

As mentioned earlier, I believe the external diode method can be applied to the original scheme for insulated-rail (no relay) control of the original (incandescent bulb) 153 or equivalent.  This could potentially solve the dim-bulb "problem" of that method.  I can elaborate if there's any interest.

All I need at this point is suggested values for the diodes and resistors and it's off to Radio Shack* for me! 

Thanks! 

@shorling posted:

I can report that I use hundreds of Town and Country Lionel direct replacement LED bulbs on my layout.  These LED bulbs have been on my layout for over 10 years with zero failures.

I've dropped them a line about buying a box of 50 clear LEDs, half screw and half bayonet, for experimentation purposes.

And as we all know, when the Razorback Traction Co. starts experimenting...   Well.   

Mitch

*Yes, I'm one of those lucky sods who still has a Radio Shack in the area. 

@M. Mitchell Marmel posted:

I've dropped them a line about buying a box of 50 clear LEDs, half screw and half bayonet, for experimentation purposes.

Now that's prompt service!  Dropped a note to T&C Hobbies just now, and got a reply five minutes later saying that one could, in fact, mix and match!  These folks are obviously on the ball!   Kudos! 

Mitch

@M. Mitchell Marmel posted:

*Yes, I'm one of those lucky sods who still has a Radio Shack in the area. 

With their meager inventory of discrete parts, it's not nearly as lucky as when they actually catered to the hobbyist and had tons of selections.

GRJ, are your relays in stock?  I didn’t find them on the website.

I'll have to check with the store, they must have screwed up the website.  I know they have them in stock.

Drop me a email and I'll fix you up.

@gunrunnerjohn posted:

With their meager inventory of discrete parts, it's not nearly as lucky as when they actually catered to the hobbyist and had tons of selections.

Sweet and pure truth.  Still, better than nothing.

Mitch

@M. Mitchell Marmel posted:

All I need at this point is suggested values for the diodes and resistors and it's off to Radio Shack* for me!

A good starting point for the resistor if Radio Shack (click on the link):

470Ω ½W 5% Carbon-Film Resistor (5-Pack)

Kind of floors me that they charge $1.50 for a 5-pack but if this is all you're buying I suppose mail-order shipping would far exceed that.  Resistors like this should be a a nickel or so in small quantity.

If you only have the non-diode LED bulbs and need to add the external diode, Radio Shack appears to have an assortment of 25 diodes for only $3.50 (any of the 25 would work in this application) which is actually not unreasonable (click on the link):

Rectifier Diode Assortment (25-Pack)

I have fond memories of Radio Shack - especially their Free Battery Club punch card or whatever it was called - of course you couldn't get alkalines LOL.  Anyway, I looked up these 2 items in my paper Radio Shack catalog from last century and inflation is not that bad...

@gunrunnerjohn posted:

Well, it has a 10A relay, so it could power quite a few things.   Here's a simple diagram of it connected to a red/green signal, likely one of the simplest uses.  In this configuration it's powering the board from the track voltage, and the signal from external power.

For conventional users, it's frequently useful to power everything with external power, that is easily accommodated.

You'll note in this example, the track center rail is not used as we derive no power from the track, just trigger on the insulated rail to switch aux power.  The outside rail is represented, that is because to use the insulated rail technique, your aux power and track power must share a common ground.

Hey John....Where could I buy one of these (or several)?

@trainmanmason posted:

Hey John....Where could I buy one of these (or several)?

Insulated Track Signal Driver, Rev. 2

I didn't read all of these but if not mentioned, Dallee makes a relay that does the job without all the fuss.