Kato switch monitor

[BMK]

I have 20 Kato style switches and crossovers and a Digitrax DCC on my N-Scale layout. I would like to install status LED’s next to the switches (trough and change) and on the control panel. The attached circuit works but would need to purchase a trackside Dwarf two lite signals which has both pair of LED’s for connection to the output of the IC. The N.J. Accessories No. 2013 has a common lead and two LED leads. Does anyone have suggestions on a signal with four leads or a circuit I could add to allow connection to the N.J. Accessories No. 2013 or similar signal?

 

[TomR]

I have 20 Kato style switches and crossovers and a Digitrax DCC on my N-Scale layout. I would like to install status LED’s next to the switches (trough and change) and on the control panel. The attached circuit works but would need to purchase a trackside Dwarf two lite signals which has both pair of LED’s for connection to the output of the IC. The N.J. Accessories No. 2013 has a common lead and two LED leads. Does anyone have suggestions on a signal with four leads or a circuit I could add to allow connection to the N.J. Accessories No. 2013 or similar signal?

That circuit is nothing but a simple flip-flop.

The output is two + outputs that go high and low, and they bridge the LED's between them. This creates a reversing polarity, depending on which side is low and high.

How you connect to the other dwarf depends on if it is common anode, common cathode, or a simple series connection with a center tap. All would need appropriate current limiting resistors.

To drive common cathode lights with DC+ with repect to ground, you would simply put the LED's with common towards ground, and one hot lead from 7 and the other from 14 to ground.

To drive a common anode LED system you would put the common anodes to the +12 volt supply and the cathodes individually to 7 and to 14.

To drive a series connected LED system with a tap the tap would float and one outer end connect to 7 and the other outer to 14.

I'm not sure how the lights you use are wired. I make my own dwarfs because it is so easy and I am cheap. I use a series connection for LED's with no taps. Mine are a two-wire system that reverses color (top LED or bottom LED) with polarity.

 

[BMK]

Tom
Thank you for the reply.
I did all three suggestions and all worked as you stated.
Attached is the circuit as I will be using it.

 

[TomR]

Tom
Thank you for the reply.
I did all three suggestions and all worked as you stated.
Attached is the circuit as I will be using it.

Yes, that looks fine. Apparently yours are common anode LED's

I use different resistor values on red and green to keep the red brightness down a bit. Red looks too bright at the same current as green, so I use more resistance in the red direction.

By the way, another hint. You have limited current with the 4011. If you want to run a bunch of LED's, series connect similar colors. That's what I do so I can run several LED's from one single 20-30 mA source.