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Extremely Cheap Dwarf Signal

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  • Member since
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  • From: Dearborn Station
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Posted by richhotrain on Saturday, August 4, 2012 4:01 AM

LOL

I have a 2.75 year old grandson.

Love him dearly and that sounds just like something he would say.

Rich

Alton Junction

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Posted by NP01 on Friday, August 3, 2012 7:16 PM

2.5. He is my reason to escape to the basement. 

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  • From: Dearborn Station
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Posted by richhotrain on Friday, August 3, 2012 12:50 PM

NP01

This should excite my toddler, "red light stop" .. "lello flash branch line" ... "oh oh yellow flash going yard, daddy switch track"

LOL

That's great.

How old is your toddler?

Rich

Alton Junction

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Posted by NP01 on Friday, August 3, 2012 8:56 AM

So I found that if I unbend the leads and carefully pull on the LED lens, I can take the LED out. This should allow me to put in any 3 mm LED in its place! I ordered some Yellow Flashers which will (hopefully) arrive in time for some weekend work on points indicators for diverging routes. 

So now I will have two R/G in the trailing point direction so trains won't go wrong way in (I keep doing this and with the tortoise it's a definite derail for cars) + one flasher on certain diverging points which are just OFF (need a parallel reverse diode) when mainline route is set on the facing point direction. 

This will also drop the voltage to the tortoise to 6 volts, which I find interesting. I am glad I did a +/-12V supply to start; for a while I was considering lower voltage and that would have stopped me from doing three LEDs in Series. But maybe I will do some series parallel. 

This should excite my toddler, "red light stop" .. "lello flash branch line" ... "oh oh yellow flash going yard, daddy switch track"

  • Member since
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  • From: Western, MA
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Posted by richg1998 on Sunday, July 29, 2012 2:29 PM

rrinker

 Yeah but that kinda defeats the purpose of just wiring the LED ins eries with the Tortoise motor - if you're going to have to build a circuit to do it, might as well use the re3d/yellow 3-leg LEDs and wire it to a Tortoise contact, no active electronics needed, just a resistor. To get yellow from a red/green LED you have to use asymmetric AC to balance out the fact that the red tends to overwhelm the green side. Part LED characteristics and part human eye perception of various colors. For example, to me the track status LED on my Zephyr looks red, even when address 00 is at speed 0. At best it gets kind of yellow when you run address 0 in the direction that produces more green. More of an orange to me. CHange direction and the red washed out any bit of green and it looks like a plain red LED.

                            --Randy

 

Correct.

It will not apply easily to using the tortoise but for block signaling, it worked very well. I like working with logic circuits.

All we had at the time where PFM slow motion machines. We were not concerned with yellow for sidings.

We do not count all the rivets in our club.

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.

  • Member since
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  • From: Reading, PA
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Posted by rrinker on Sunday, July 29, 2012 1:47 PM

 Yeah but that kinda defeats the purpose of just wiring the LED ins eries with the Tortoise motor - if you're going to have to build a circuit to do it, might as well use the re3d/yellow 3-leg LEDs and wire it to a Tortoise contact, no active electronics needed, just a resistor. To get yellow from a red/green LED you have to use asymmetric AC to balance out the fact that the red tends to overwhelm the green side. Part LED characteristics and part human eye perception of various colors. For example, to me the track status LED on my Zephyr looks red, even when address 00 is at speed 0. At best it gets kind of yellow when you run address 0 in the direction that produces more green. More of an orange to me. CHange direction and the red washed out any bit of green and it looks like a plain red LED.

                            --Randy

 


Modeling the Reading Railroad in the 1950's

 

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

  • Member since
    October 2006
  • From: Western, MA
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Posted by richg1998 on Sunday, July 29, 2012 1:33 PM

Some have done this in the past. Many red/green LED's produce a sort of yellow when AC is applied to the bipolar LED. It can be done with logic circuits. I found a MRR magazine about ten years ago with the logic circuits describing how this can be done.

 

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.

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Sunday, July 29, 2012 1:29 PM

 Only ones I've found with red/yallow are 3-lead, so you'd have to use a resistor and the switching contacts on the Tortoise. I suspect a 2-lead red/yellow is going to be tough since the red/green combo makes yellow (sort of) on AC. I do see some other color combinations finally available, maybe potential for other applications, if not signals.

                       --Randy

 


Modeling the Reading Railroad in the 1950's

 

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

  • Member since
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Posted by NP01 on Sunday, July 29, 2012 1:21 PM

Yes, one of these. 3 mm 2-lead bipolar Red/Green, with black housing and leads bent 90deg. I soldered two wires to the leads, put a piece of insulating tape between and around the leads and just dropped them into a 1/4" hole in the bench work. Throw some ballast around and set the ballast ... Good to go for 80c and some wire!

I did not find Red/Yellow. I need to find a black straw with 3-mm diameter which I can cut in a semicircle shape to glue on top to make the visor. 

NP. 

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  • From: Dearborn Station
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Posted by richhotrain on Sunday, July 29, 2012 5:21 AM

Is this the product you are referring to?

http://www.quickar.com/discrete.php?session=qwNCb8AN

I bought some of those and they are pretty neat even if not prototypical.

Rich

Alton Junction

  • Member since
    May 2012
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Extremely Cheap Dwarf Signal
Posted by NP01 on Saturday, July 28, 2012 7:31 PM

Just installed my newest eBay acquisition - dwarf signal from Quickar Electronics. They went on in series with my Tortoise turnout motors. For 80c a piece, I really like them - nothing was cheaper.the signal is very simple: a bipolar LED with bent leads placed in a black box measuring 4 mm x 5 mm x 5 mm.

I am sure they are not prototypical. But I really did want some signals on my layout and I am quite far away from setting up a computerized system. 

I surely recommend for someone whohas Tortoii. 

NP

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