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I've been working diligently on updating my 4 Santa Fe passenger cars (people and LED lighting).  I'm on my last one, the 6-19179 observation car.  I am following the suggestions from this thread pretty closely.  My tail lights are very similar (but not exactly) to those posted by @stan2004, but I'm using, basically, the lighting method suggested by @gunrunnerjohn.  I'm planning on using CA to glue 3mm warm white leds to the lenses, but the lenses are so thick.  If you reference the picture at the end I've put in blue lines where I think I'll cut off the excess plastic from the lenses.  There will still be a nib on the lens to hold it in place.  My thinking is that the bulbs will be closer to the where the light is seen, also it makes it a bit easier to work with, especially with the clear lens.

My question is, has anyone done this?  My only concern is that when I cut off the ends of the lenses, the new ends will not be smooth.  Does this cause significant problems on how the light passes through the lens?



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I think that the function of the extended base on the red lights in this generation of observation cars was to collect light from the car’s overhead lighting and use it to illuminate the markers; they had no separate light bulb although in some cases the tail light did. These are not fiber optic materials, just solid plastic, and I think were called light pipes. They really don't make the markers as bright as you might want.

Anyway, I did what the OP suggests and cut them down to mount led’s on the flat cut side, which certainly improved the light. I then actually drilled into the lenses to mount small SMD led’s inside of them, which was a chore but concentrated the light still further. That’s probably unnecessary for most people’s purposes given that the base was designed to collect light anyway, and led's are bright enough to provide plenty.

This video still shows how the lighting turned out. The tail light is actually a Mars light as per the original plans of this car, the Texas Special Stephen F. Austin, made using an Ngineering Mars Light simulator board; the car is aluminum-bodied from a Lionel set made some years ago:

63144186-143E-4EDA-B193-74119D10197E

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Last edited by Hancock52

GRJ is right, but . . . GGD has routinely used red led's on their observation cars where the lens is actually clear except when illuminated - doesn't look very realistic, though, when there is no power to the car. You can color the lens with any transparent red paint, or stop light red that has been thinned a little bit. I think that the same applies to Lionel lenses.

@Hancock52,

Thanks, I'll be using your method.  I have an LED strip attached to the top beam of the car, so connecting the wires for the tail lights to it should be simple.  I'll be using rounded 3mm warm white LEDs for this.  I'll drill into the modified plastic lenses as far as I'm comfortable doing, and then CA glue the LEDs in.

I tried using the spare LEDs from strips, connected to the strip as per @stan2004, but I was never able to successfully solder them to the strip.  My strip did not look like Stans though.

On a related issue, the drumhead (I believe that's what it's called) was lighted with a tiny little incandescent light.  While I was messing around with the lights, and they had been on for a while, I accidentally touched the bulb.  It was incredibly, incredibly hot, so much so that the plastic holder for it was starting to soften.  I'm guessing that after a while, the heat from it would have discolored the plastic drumhead symbol.  I wasn't planning on modifying that light, but I replaced it with a nice 3mm LED.

BTW, these cars are new, and I've only had them on a test track to check out the lights.

@Pingman posted:

...

Has anyone "painted" the clear plastic lens LIONEL uses to replicate the prototype's red lens?  If so, shat did you use?

@Richie C. posted:

If you paint the lens, something like Tamiya Clear Red will work. You may have to re-apply a number of times to get the shade you desire.

What he said.  Any hobby shop that sells plastic model kits will carry it.  The frustrating thing is you'll only need about 1 drop to color all your lenses leaving you with a full bottle of paint which you may never use again!  It has a mildly "sticky" syrup-like texture that helps it adhere to a clear plastic lens. As stated, multiple coats darkens it so you can get it to your liking.

x-27

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Last edited by stan2004
@texgeekboy posted:

@Hancock52,

Thanks, I'll be using your method.  I have an LED strip attached to the top beam of the car, so connecting the wires for the tail lights to it should be simple.  I'll be using rounded 3mm warm white LEDs for this.  I'll drill into the modified plastic lenses as far as I'm comfortable doing, and then CA glue the LEDs in.

3mm LEDs are generally what I use for Diesel engine headlights and Mars lights on steamers. They are generally very bright and you need to be careful that light does not escape around the base or you will find your car/engine interior brightened up by them. I’ve had to seal bulbs of this size in to prevent that.

In the end I used flat surface mount LEDs in my observation car project, although they had to be installed at a slight angle inside the lens to cast light through the whole of it, which was not an easy task. There are 1.8mm LEDs you can use but the base of these is larger than the bulb. I think that I also used red LEDs from Evan Designs in this project, and they are independently powered from the overhead lighting.

Someone more expert than me can advise on this but I would have thought you’d have no voltage issue with warm white LEDs tapping into a strip of the same kind of bulbs. However, in my last project adding two very small (Z size) LEDs to a stock recent model (2020) Lionel LED overhead lighting strip to illuminate markers at the rear of the car, they dimmed down the strip in a way I did not expect. I swear by GRJ’s passenger car lighting modules, which are better than Lionel’s super-capacitor strips.

Last edited by Hancock52
@Hancock52 posted:
Someone more expert than me can advise on this but I would have thought you’d have no voltage issue with warm white LEDs tapping into a strip of the same kind of bulbs. However, in my last project adding two very small (Z size) LEDs to a stock recent model (2020) Lionel LED overhead lighting strip to illuminate markers at the rear of the car, they dimmed down the strip in a way I did not expect. I swear by GRJ’s passenger car lighting modules, which are better than Lionel’s super-capacitor strips.

Paralleled LED's can be a problem unless they're exactly matched.  Even two different brands that are both claimed as being a single color can react differently with operated in parallel.  The issue is simply the sharp knee of voltage vs current for an LED, a slight difference in the manufacture of the chip can result in poor performance in parallel.

I routinely wire LED's in parallel, but only those from the same manufacturing batch.  Others I use a resistor in series to equalize the currents.  If you look at how the typical 12V LED strip lighting is constructed, there are three LED's in series with a small resistor in the 100-150 ohm range.  The function of the resistor is to swamp out any minor LED characteristic and to insure each three LED segment is the same brightness.

I think many people have discovered that if you parallel a red and green LED that the red one lights and the green one doesn't.  That's easily explained as the green LED has a higher operating voltage then the red LED.  The chart below illustrates the issue.  Note that the green LED at 20 milliamps requires about 3V, and the red one requires a bit less than 2V.  Since LED's are a current mode device, if you adjust the current to 20ma for the red LED, the green one will never get to the voltage to light at all, or might light VERY dimly.

Light Emitting Diode [LED) - Last Minute Engineers

The best way is to add balancing resistors to the two LED's.  Since you almost always need a resistor with an LED unless you have a current limited voltage source, you just use a resistor for each LED.  Let's say you have 5VDC for a power source and you'd like to light the LED's to full brightness.  You'd use a 100 ohm resistor for the green one and a 150 ohm resistor for the red one.

@TedW posted:

So what do we do to get them to both light?  Red and green, add a resistor to one or the other or…?  Thx in advance.

Run Separate power wires with different resistor values  from your pickup connector or somewhere inside to your Red and  Green LED's. Use this to figure your resistor value needed.

http://ledcalc.com/#calc.

Enter in your DC Input Voltage

Dropping Voltage (2.0 for Red) (3.0 for Green) (3.4 for White)

Milliamps (20)

Number of LED's

Move screen to Right and click on for Series Wiring or Parallel Wiring for whichever you plan to use as if using more than 1 LED  like a Green and White light together it will figure differently (just split the difference of 3.0 V and 3.4 V by using 3.2 Volts power drop.)

Go back to left and hit Calculate for your first color LED, it will tell you below what is the actual resistance, look to the right, it will recommend the next higher value resistor that you should use and the resistor wattage needed, usually 1/8 or 1/4 watt. Write it down, then do it again for the other color resistor, and write that down. Get the correct resistors and make sure you connect positive hot power to the resistor and the longer or positive lead of the LED, then you can connect the return leads to your your return power connector. Good luck with your project.

Last edited by Gary P

It's actually pretty easy to calculate resistor values in your head for common 20ma LED's.  You also don't have to be exact, just err on the side of more resistance and not less.

For each volt you need to drop from the power to the rated voltage of the LED, use 50 ohms.

For example, you are using a 12VDC power source and want to light a white LED.  You need to drop 9 volts as the white LED has a 3V operating voltage.  9 times 50 is 450, so a 470 ohm resistor is a very common value and is a perfect choice.

Thanks for all this great info. The conversion cars look great.  I have done some similar but to keep it simple with the wiring use the Evans LED's for variable voltage they work great. I was wondering about a suggestion for an even softer light for the tail end lighted train sign name? The LED's are bright and have a very concentrated light pattern where as the regular bulbs are not as intense and spread the light more. I know you can use light diffusers and dull the light a bit but just curious on ideas for the tail end lighted signs.

https://evandesigns.com/collec...eds-for-transformers

@kj356 posted:

Thanks for all this great info. The conversion cars look great.  I have done some similar but to keep it simple with the wiring use the Evans LED's for variable voltage they work great. I was wondering about a suggestion for an even softer light for the tail end lighted train sign name? The LED's are bright and have a very concentrated light pattern where as the regular bulbs are not as intense and spread the light more. I know you can use light diffusers and dull the light a bit but just curious on ideas for the tail end lighted signs.

https://evandesigns.com/collec...eds-for-transformers

Maybe spraying them with dullcoat, Krylon matte clear or frosted clear.

@kj356 posted:

Thanks for all this great info. The conversion cars look great.  I have done some similar but to keep it simple with the wiring use the Evans LED's for variable voltage they work great. I was wondering about a suggestion for an even softer light for the tail end lighted train sign name? The LED's are bright and have a very concentrated light pattern where as the regular bulbs are not as intense and spread the light more. I know you can use light diffusers and dull the light a bit but just curious on ideas for the tail end lighted signs.

https://evandesigns.com/collec...eds-for-transformers

Lionel uses multiple small LEDs in the drumheads they’ve recently produced - 4 in fact arranged on a circular mount. This spreads the light, which won’t happen with a single LED pointed straight at the back of the sign. I once tried using a single flat “Mega” LED from Evan Designs and actually had to mount it at the base of the sign angled slightly back at a reflective foil insert. It still has a hot spot in terms of brightness near the center of the drumhead.

Thanks for ideas on the tailend sign lighting. I was by the hobby shop today and picked up some more Evans LED's. And some grain of wheat bulbs. I tinkering with putting crumpled foil in the back of the little light box for the sign then aiming the LED backwards (away from the sign) onto the foil. But need the really tiny LED bulbs to fit through the existing holes.

Will try the grain of wheat bulbs first with a light diffuser behind the sign. (can use the foggy/ semi transparent plastic milk cartons or the yogurt lids for diffusers.)

On the red tail end lights I use the red Evans LED's.

Have been looking for a good LED light for the caboose or observation style old style oil lamps that have different colored light lens front, side and back. The LED's again are to directional whereas the Grain of Wheat bulbs give an even spread of light to all sides.   

@kj356 posted:

Have been looking for a good LED light for the caboose or observation style old style oil lamps that have different colored light lens front, side and back. The LED's again are to directional whereas the Grain of Wheat bulbs give an even spread of light to all sides.  

Is there a GOW bulb small enough for this purpose? Below is a photo of a project where I added caboose marker lights to the rear of a Lionel Business Car, which was fitted with them during a UP 150th anniversary excursion. The marker lights are scale brass and far too small to fit a bulb inside. I used Evan Designs Z size flat LEDs, which are tiny and very bright. Mounted slightly recessed in the side of the marker next to the car body, they illuminate all three lenses in it pretty well - in this case with a slightly muted effect as I suppose you might get with an oil lamp. (That was unintentional because this is the car I mentioned above where the marker lights are wired to the overhead LED strip, to which the drumhead lights and tail light are also connected in the stock assembly. The interior is only as bright as it is because there are several separate track-powered LEDs to light fixtures on the compartment walls and a couple of other lamps.)

D59B3D12-3E79-4C75-89CF-488DDAFD3F14

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Last edited by Hancock52

It would be a piece of cake to make a small PCB that mimicked the Lionel one, the key is how universal a fit would it be for other brands?

Yup, and as we all know, there are square/rectangle “drumheads” also.  My very unscientific measurement of 10 round ones and 4 “squareish” was 1/2” each.  When I drew a close enough half inch circle and put four 3528 leds in there, I’m thinking that’s gonna be a lot of light.  Would need to be dimmed down quite a bit to reduce or eliminate the glare.  Resistors or something?  Or use Nano/Pico/Z size led.  Very difficult to work with…  (click for larger image)

87F8A4FA-FD80-4EC0-8868-020DCD9EB0AB  E0FF4AA7-A9B8-4BEF-A179-6F32A637B660

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Last edited by TedW
@TedW posted:

Yup, and as we all know, there are square/rectangle “drumheads” also.  My very unscientific measurement of 10 round ones and 4 “squareish” was 1/2” each.

Do you have some photos or measurements that show the "depth" we are working with?  That is, what is the distance from the back of the drumlight chamber to the back of the logo window?  I realize it varies but trying to get some ballpark numbers.

Did the GOW versions have bulb that fit in this chamber?  IIRC usually the smallest GOW bulbs are maybe 1/8" diameter?  Is that how little room there is to work with?  I'm think of a single LED as thin as possible and as far back as possible with some clever shaped (3D printed?) diffuser.

Not sure how helpful this will be, but the measurements I could get readily were so different cause the designs were so different.  MTH heavyweight was 5mm thick, I installed a 3mm led there years ago.  The Lionel streamlined cars have a 3mm “gow” lighting an endcap design, indirectly.  Many weren’t lighted at all.  So I’m pretty sure one has to approach the task on a case by case basis.  But here are some photos if they help any.

093880EB-14F4-4F3F-A5BC-60AF271A1D45D4892533-C614-4094-BDF3-D8EE283FF8943E66B22D-6536-4AC4-BC36-355CB37AF61349E5BB10-DBDA-4634-B492-C46F061F37CD1AB075E3-457A-4623-B227-EEF91F57186D

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@TedW posted:

Yup, and as we all know, there are square/rectangle “drumheads” also.  My very unscientific measurement of 10 round ones and 4 “squareish” was 1/2” each.  When I drew a close enough half inch circle and put four 3528 leds in there, I’m thinking that’s gonna be a lot of light.  Would need to be dimmed down quite a bit to reduce or eliminate the glare.  Resistors or something?  Or use Nano/Pico/Z size led.  Very difficult to work with…  (click for larger image)

87F8A4FA-FD80-4EC0-8868-020DCD9EB0AB  E0FF4AA7-A9B8-4BEF-A179-6F32A637B660

I don’t have a photo of the Lionel LED drumhead board I mentioned earlier in this thread, but I can tell you that it did not have square 3528 LEDs in it; instead they were much smaller rectangular surface mount ones - in shape more like a 5630 but smaller. (Come to think of it, they are about the same size and shape as standard “chip” size surface mount LEDs.)

I actually don’t find the pico or nano or even Z size LEDs I get from Evan Designs hard to work with BUT of course they come pre-wired. Trying to solder wires to LEDs this size is not something I attempt any more!

Last edited by Hancock52

Here's what I'd do for the drumhead.  This is a .4" board, it could be smaller if it didn't fit in the drumhead.  Three bare boards are 80 cents at OSHPark.  I used 0603 sized LED's, they could be the next size larger and still fit on this board.  The resistor is selected for the intensity you desire, probably a fairly high value for something as small as a drumhead.  The board is .03" thick.  The LED's are only a couple mm tall.  The board could also include a standard diode so it would run directly from track power.  You could also reverse the polarity of a couple of the LED's and eliminate a separate diode for AC operation.

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Last edited by gunrunnerjohn
@texgeekboy posted:

@TedW,

If you don’t mind, can you post links on where to buy the pcb and lights?  I’ve looked for them and am not sure about what I discovered.

For expediency, I get the pcbs from OshPark.  So download this attached Gerber file that GRJ designed into a location you remember.  Load the OshPark site, OSH Park ~, and the page will ask for your file, navigate to it, select and OshPark will automatically load the file and display your board.  set up your account to order, remember it will quote 3 boards at $2.30 shipped.  One board has six pcb on it.  So I ordered 6 boards per batch of three(2 batches) $4.60 shipped.  That's 36 pcbs.  select option "2 oz copper, 0.8mm thickness".  That's pretty much it.  Any problems send me an email(in profile)

For the leds, got those off the bay.  Can't give you a link cause of forum rules, but a screen shot and the item number.  Put that number in the bay search box and you should be good to go.  You might be able to do better in price with a search. Hope this helps.

ebay led

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@TedW posted:

Not sure how helpful this will be, but the measurements I could get readily were so different cause the designs were so different.  MTH heavyweight was 5mm thick, I installed a 3mm led there years ago.  The Lionel streamlined cars have a 3mm “gow” lighting an endcap design, indirectly.  Many weren’t lighted at all.  So I’m pretty sure one has to approach the task on a case by case basis.  But here are some photos if they help any.

...

093880EB-14F4-4F3F-A5BC-60AF271A1D45..

...

49E5BB10-DBDA-4634-B492-C46F061F37CD.

...

Thanks for the measurements.  I do not have any cars with drumhead lights so this was very instructive as to what the issue is in the first place!  I get it now!.

A multi-LED custom PCB may be one way to spread the light...but I'm thinking you would now just have multiple hot-spots..even with some kind of diffuser lens...though perhaps looking better than one glaring hot-spot in the middle.

I've been experimenting a variable filter to "equalize" the distribution of light.  I am mindful that there is only about 3mm of depth to work with.

high school science project

So, for example, I concocted the round filter shown in the inset that blocks more light in the center but then tapers off to the edges.  My cheesy drawing program can't draw smoothly decaying gray ring so as shown it's just 4 rings just to mess with.  The idea (open to suggestions) is to put a couple layers of diffusing material (plastic yogurt lid), then the filter, then another layer of yogurt lid.  So in the end it would be a round 3mm thick filter you plop over the LED to diffuse and equalize the light.

The key is to recognize we have more light than we need to start with.

Again, just a work in progress but I figure something anyone can do at home without special equipment, tools or what not...

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Last edited by stan2004

@gunrunnerjohn, suppose we should get a gerber file and order a few of the pcbs and start playing around.  That is if you haven’t ordered any already.  Obviously, I have too much time on my hands.    I have to get some of those tiny leds too.  Might be to much for me to handle…  BTW, what resistor value would you try?  Maybe 470ohm?  I have a resistor whachamacallit, to check different values, but no smt resistors, so I’ll have to get some of those too.  I do have some 200ohm ones.

Last edited by TedW

The LED's on my little board are this size.

SmartLED SMD Side 

Digikey has them: Osram LW L283-Q1R2-3K8L-1-Z, white.

The resistor in the board is an 0805 size resistor.  They come in power ratings up to 1/2 a watt.  I suspect that for this task, we'll light the LED's pretty dimly, so the standard 1/8 or 1/4 watt ones should do the trick.

The resistor value is totally dependent on the amount of light you want.  The Drumhead shouldn't be another headlight, so the resistor value is going to be at least 1K I would expect.  I'd probably pick up a few 470, 1K, 1.5K, and 2.2K values to start and see how it works out.  Also, the resistor value is TOTALLY dependent on the input voltage.  If you're going to try to run this on AC, swap the polarity of a pair of the LEDs, that will provide reverse voltage protection for the whole lot.  For DC, they have to be as shown, the little stripe is the cathode.

Here's the Gerber files.

Drumhead 6 LED Board Gerber.zip

Here is the complex schematic of the board.

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I pulled that "olympian" drumhead out of the end of the car.  Suppose you could say it's not mint anymore.  Tore out the 3mm led and put in one of the ground light pcb with a 3528 led.  Couple of layers of paper and see what you think.  This may be a solution looking for a problem 🤷‍♂️.  YMMV    Click for larger images:

143AD6EC-1F1E-40B6-A46D-51729591BC7C DCBFD524-DF18-4F2A-9666-33AA8B26BC26 6E4B0AB5-B621-420C-95B0-BBA458296509 82B1D098-3EE9-455B-A9F6-5B854E56A91F C46F36F0-1C34-48A5-A5D1-FF26C700AC16 979AD172-4B76-47F9-9991-DAD2825D9357 C68F69E7-9A12-4A59-8045-808180C5B84E

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Since I was the OP, I figure I need to let y'all know the outcome from my original post.  I've attached 3 pics to help with my explanation.

The first, 'Original Roof' shows the back of the observation car with the factory lenses.  My question was should I cut off the large part of the lens sticking out before adding LED lighting.  After a lot of discussion, I proceeded with drilling holes in the lenses to insert 3 mm LEDs.  Since my drilling of tiny holes was significantly impacted by my large banana fingers, that was a failure.  I bought another observation roof on the bay with similar lenses, and painted it so it looked pretty good.

Looking at all the posts, I thought about simply gluing the leds from a light strip to the lenses, and connecting that small strip to the end of the long LED strip on the ceiling.  I first glued the LEDs to the unaltered lenses.  I think there were 9 LEDs in that strip to get around all the big lenses.  The resulting light output wasn't that good.  I even glued 2 LEDs , one to the front and one to the back, of the large lenses.  I still didn't think it was good.  Sorry, no pics of that effort.

I then cut off the large end part of the red lenses, making a flat surface, and glued one led to each lens.  I used a small strip of 6 LEDs for this, and you can see it in the 'Modified Lenses with Lights' picture.  I was originally going to put liquid tape over the extra lights, but I thought the end of the observation car could use the extra light.

The 'End Result' picture shows what it looks like.  The lenses are very bright IMO.  I also replaced the factory installed GOW bulb for the drumhead with a 5 mm warm white LED.

My work will not win any accolades from the electrical techs out there, but it works okay

Update:  I didn't have the pic of the original roof, so I just copied it and then reposted it.  The image is pretty small.  If you want to see it bigger, look at the first post in this thread.

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Last edited by texgeekboy

Well boys and girls, this is me tapping out.  I'm sure a "I coulda told you so" smile is starting across your faces as I look over the drumhead pcbs I just got in the mail.  They are too small for me to tackle with the soldering of 0603 leds.  Then a resistor and hookup wire on top of that, above my pay grade.  And I have a whopping $3.20 in a dozen boards.  Anybody want some shoot me an email and they are yours.  Probably will mail in a standard first class envelope.  I wish you well with this little project.  🤷‍♂️

12264255-4BDA-4ECE-9FC3-261231803BC7 6A536BBE-15E4-44AF-9A9D-CFCFFA876110

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@TedW,

Kudos for the attempt!  I wouldn’t have even tried it since that level of detailed work is way above my pay grade as you say.  Since your drumhead was separated from the car, I was luckier with mine being attached to it and already being lit with a GoW bulb.  I replaced that with a LED and from my pic above I think it came out pretty good, I’m happy with it anyway.

@TedW.  I received my boards last Thursday, didn’t open the envelope until Saturday.  Thought pretty much the same thing as you, doubt that I will successfully get the LED’s soldered on the board.  I might attempt it at some point but since one LED costs more than three of the boards, maybe not.  I bought six boards because buying only three seemed like I was being “cheap.”

I also bought six of the single LED boards, I already have LEDs for them.

Last edited by GregM

Yes, you have to do a little searching if you go offshore, so I don't like to specify a specific link for those.

Here's a couple of a zillion links on Aliexpress:

100pcs 0402 0603 0805 1206 1210 3528 5050 5730 smd led Red Yellow Green White Blue light emitting diode Clear LED Light Diode.  For less than $2.50, you get 100 LED's.

100pcs SMD LED 0402 0603 0805 1206 LED Chip Light Emitting Diode Highlight Red Yellow Blue Green White Light Orange Lamp Beads

So of course this little drumhead light got to working on me as we all know can happen in this hobby.  So, I got the leds, weaponized the hakko with a new tiny tip and some .020 solder and went to work.  Went together better than I thought it would.  But, no joy.  It won't light.  Powered at 3vdc, individually, each led lights, but of course that doesn't test the circuit.  I get no continuity.  Should I?  What else should I check?  I think I have the led polarity correct throughout.  Any help out there on troubleshooting this pcb lighting module?  Here's some photos, but not sure how much help they'll be.  Thx in advance.

B93520C2-3B25-4A57-98F0-F36A70A8D3630667306C-D43F-4AD1-83B0-B2BEEE6B094B1F7220E7-B480-4A1E-9CE1-D083059F9707

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  • B93520C2-3B25-4A57-98F0-F36A70A8D363
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  • 1F7220E7-B480-4A1E-9CE1-D083059F9707

what value resistor are you using?  It will take at least six volts to light it if it's the circuit I posted.  There are three sets of two LED's each in series, and the three sets are in parallel.  If you put at least 5.5-6.0 volts on it, it'll light.  That presumes that all the LED cathodes face the proper direction, see arrows in the graphic below.

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Well, that was easy.  Shoulda tried more voltage, but afraid to blow something up as they are 3vdc led.  Didn't know how the circuit worked.  Presumed it they were in series?  This is 5vdc with a jumper across the resistor pads.  Is pretty good that way, but using your thumbnail resistor calculator, from 12 to 6vdc would take around 300 ohms , so use a 330ohm resistor, and we're golden.  18vac would be a diode and around 660ohm.

26F6F936-D226-40DC-B597-4FF40E4FC89D6F441B9B-2F20-44A6-B0E5-B5FD3FA061F09F72B5F1-4672-44D0-8CD4-719E29A43141

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  • 9F72B5F1-4672-44D0-8CD4-719E29A43141
Last edited by TedW

At 12 volts DC, any resistor from 150 ohms or larger would be suitable.  Obviously, the 150 ohm resistor would probably result in REALLY bright lighting, so I'd be guessing more along the lines of a 1K or so resistor to tone the amount of light down.  The whole idea of the multiple LED's is to spread the light evenly, so each one shouldn't be like a miniature sun.

@TedW posted:

That's weird.  I work on an iPad.  And, they showed up on my post and yours, on mine.  So, anyway, reloaded them in original post.  Did that work?

Yes, pictures show now in your post but not my previous one that was just a quote of your post.

I deleted my quote post since it is incorrect now that you reloaded the pictures.

This is a screenshot of what I saw before the pictures were reloaded.  Sometimes odd things happen here on the forum.

062D11F7-B6D6-4E4E-ADAF-142453477BBC

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