# Overton Coach Lighting Phase II



## Lemonhawk (Sep 24, 2013)

I revised the power supply using a larger 330 uf cap and an SMT resistor. If anyone needs a 120 Ohm SMT resistor, there are a few somewhere on my workshop floor! I also tried some "lampshades" on the LED light bar to really tone down the amount of light. The power supply consists of a diode bridge, a resistor and a capacitor, the CL2 current limiter mounted on the light bar.
First picture is the old power supply, second is the new version with the SMT resistor just visible behind the vertical lead in the foreground from the radial capacitor instead of the SMT one that was used in the old version. Last picture is the coach, note that the LED closest to the Camera has the Lampshade while the 2 in rear do not. The shade makes the light a lot dimmer and I think I'll stick with the shades. I also think I'll go back to the 120 uf SMT cap when I do the Baggage and Combine and use this larger version to the Baggage and the smaller version back to the Coach. I did get a really small tip for the solder station and am getting better at working with these little beasts. I thought the LED's were small but the resistors are miniscule






















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## gunrunnerjohn (Nov 10, 2010)

I limit my designs to 0603 sized SMT parts so I can handle them and build prototypes and small quantities. I once mistakenly specified a 0201 resistor, I couldn't even pick the sucker up with my tweezers! hwell:


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## Lemonhawk (Sep 24, 2013)

It appears by pure luck the resistors 1608 size. There must be better tools to hold these things than the large almost useless tweezers. I have a large needle in a pin vise that seemed better at pushing them around. This also flipped a few on the floor to be lost forever. I made this while waiting for the launch of the Delta Heavy Rocket, seemed better than just waiting out the weather. Saturday looks no better.


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## jlc41 (Feb 16, 2016)

Okay guys being new to this hobbie, how does the power get to the power supply to light the lights??


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## gunrunnerjohn (Nov 10, 2010)

I use a pair of small pointed tweezers to manipulate them, and I make sure they're demagnetized and clean of any adhesive, that makes it easier to push the parts around and not have them cling to the tweezers.

The beauty of SMT resistors is when you buy them in quantity, they're almost free. I typically buy in quantity when I get them, many times I just buy the 1,000 pieces.


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## cid (Jul 3, 2014)

Lemonhawk said:


> This also flipped a few on the floor to be lost forever.


.

Haha, don't forget the panty hose over the vacuum cleaner nozzle, easily retrieves those errant parts and coupler springs!


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## Lemonhawk (Sep 24, 2013)

JLC41 - I used Kadee coupler springs. I had read somewhere that if you bend the spring parts on either side out 90 degrees you can mount the spring to the truck and the springy part will wipe the wheel. In this case I used 2 coupler springs one on each side of the truck.


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## jlc41 (Feb 16, 2016)

GRJ, Lemonhawk, I would like to light up my new passenger car also. I see in your pics that the black and red wires go to the pickups. Am assuming that the yellow and tan go to the lights???? GRJ shows a list of parts. What do I need and where can I get them?? would it be possible to get a wiring diagram??? I run a DCC layout. Thanks for posting the pickup detail.


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## gunrunnerjohn (Nov 10, 2010)

I made a lighting module that's sold at Henning's Trains, it would work for DCC with constant power on the rails. The current production uses a thinner tab that you can bend down to minimize the height of the module.









This is what's in the lighting module if you feel inclined to make one yourself. The regulator is an LM317T. The choke may not be necessary for DCC, that's for DCS.


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## Lemonhawk (Sep 24, 2013)

I'll attempt to show the parts list and circuit diagram. Just not as polished as GRJ!
The SMT resistor assorment
http://www.ebay.com/itm/141844328441?_trksid=p2057872.m2749.l2649&ssPageName=STRK:MEBIDX:IT
The LED's
http://www.ebay.com/itm/251804751292?_trksid=p2057872.m2749.l2649&ssPageName=STRK:MEBIDX:IT
I used a 330 uf cap on the version 2 that is a Nichicon RT part, its now obsolete ( I got 50 of them on ebay cheap, but there is some risk. Mouser sells the RZ equivalent. I'm a little up in the air over the cap as the 330 mf is a little big, so I may go back to the 120 uf that is in the parts list Mouser.
Select	Product Detail	Customer Part #	Order Qty.	Price 
(USD)	Ext. 
(USD)	Status	Date	Invoice #


Mouser #:	854-SP1-50X50-G

Mfr. #:	SP1-50x50-G

Desc.:	PCBs & BreadboardsSMTpad-Size1, 50x50 1 Side Pad/Grnd

1	$3.87	$3.87	1 Shipped	Apr 22, 2016	40706795



Mouser #:	647-UWT1V151MNL1GS

Mfr. #:	UWT1V151MNL1GS

Desc.:	Aluminum Electrolytic Capacitors - SMD35volts 150uF 105c 8x10

10	$0.29	$2.90	10 Shipped	Apr 22, 2016	40706795



Mouser #:	512-MB8S

Mfr. #:	MB8S

Desc.:	Bridge Rectifiers0.5A Bridge

10	$0.279	$2.79	10 Shipped	Apr 22, 2016	40706795



Mouser #:	689-CL2N8-G

Mfr. #:	CL2N8-G

Desc.:	LED Lighting Drivers90V 20mA Temp Comp

10	$0.40	$4.00	10 Shipped	Apr 22, 2016	40706795


Here's the Circuit (I did all this is a few minutes so its not very polished)







I put the CL2 on the lightbar I made from a PC tie. I just made notches on the light bar for where I solder an LED and the CL2. The pot is optional and a little dangerous, hence I did not use it rather I picked a resistor to use as this divides the 20 ma current from the CL2 between the series LED's and the resistor. I think you could put 1 to 4 LED's in series, if you need more the you may need another CL2. The PC tie was perfect for making the light bar as one side had the leds and at the end I wired a jumper between the copper sides of the PC tie which then brought the + and - connections all to the same end. Should be in the pictures of the original posting. If not ask and I'll put in another photo. I just noticed that the LED note is missing, there the 3 little squares in series at the right of the circuit.


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## gunrunnerjohn (Nov 10, 2010)

I had to "polish" my diagram sufficiently for the PCB layout package, so I actually have to specify specific parts and make sure the part outlines and solder pads are correct.


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## Lemonhawk (Sep 24, 2013)

The track input to the PS is the 2 blobs of solder on the far left of the picture and the output is the leads sticking up on the right from the capacitor. I used the same leads that were on version I so the yellow and orange wires go to a connector that connects to the rad and black from the truck and the red and black wires from the PC board is the approximate 10 volts that come out of the PS and go to the light light bar. A picture would help so I attempt a better picture soon. Maybe even figure out how to get them a little smaller!


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## jlc41 (Feb 16, 2016)

GRJ, Lemonhawk, once again, thank you very much for the circuit diagrams and parts information. Now I have to make the time to build one.


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## MtRR75 (Nov 27, 2013)

Lemonhawk said:


> View attachment 190586
> JLC41 - I used Kadee coupler springs. I had read somewhere that if you bend the spring parts on either side out 90 degrees you can mount the spring to the truck and the springy part will wipe the wheel. In this case I used 2 coupler springs one on each side of the truck.


Lemonhawk: In looking at you setup here, I wonder if the wires hinder the rotation of the truck on curves?

P.S. The picture in the quote is not showing up. To those of you who are wondering what I am talking about, see post #7.


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## Lemonhawk (Sep 24, 2013)

its running on a track that has 24" radius track and has had no problems. I can't really feel much resistance either. I think I used so leftover wire from a decoder to go from the truck to the circuit board in the coach. It was a great chance to try out SMT devices. Some of the pictures are scary, when I looked at the boards by eye they look ok, but with a macro lens on them every little blob shows up! Its still working and I put some shades on the LEDS to make it look dimmer and more like old time lights.


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