Need help with passenger car lighting

[BruceG]

Peteski, Thanks for your extensive work and write up!   I believe the poorly stripped leads were the main cause of my inconsistent results.  I’m looking forward to putting your instruction to use.  I’ll try the resistor you used, so no need to send any other.
Incidentally, I taped three resistors to paper I THOUGHT I put in the envelope. I don’t see them anywhere here, so I have no idea where they went. 

Thanks again,

Bruce

[peteski]

Well Bruce, you did include the resistors - i just missed them.    When I opened the envelope and took out the sheet of paper folded in half and the plastic box, I just read the letter which was all on one half of the sheet, but I didn't turn the sheet of paper over.  Silly me.

When I flipped the paper over I found these:


You sent me two resistors and a diode!

In your letter you mentioned that you used the large size (100 ohm) resistor in series with the LED and 9V. The LED glowed dimly.With 9V and 100 ohm resistor the LED should have been glowing very, very  brightly! How was the LED wire connected to the resistor?  I suspect that it was not soldered since the insulating enamel was not stripped. So the LED shoudl have been totally dark or gloving excessively bright.

Next, you mentioned that you used the diode (you thought was a resistor) connected to the LED and hooked it up to the E-P board.  Well, the diode drops about 0.7V in addition to the 1.7-2.0 V across the LED =2.4-2.8V.  If it was hooked up to a weak 3V source of voltage (the E-P batteries) the LED would glow fairly bright and would consume enough current to dim the white LEDs.  But diodes aren't really good for limiting LED current (like resistors do).

Actually the 3rd (small) 1000 ohm resistor would have been a good value to use when testing it with a 9V battery.  But you didn't  mention that you used it for testing.

The bottom line is that I verified the circuit to work with the 680 ohm resistor, so you should have no problem if you wire it up the way I showed in my earlier post.

[BruceG]

I may have been mistaken, writing from memory, not notes. I may have used the 1000 ohm resistor with the 9v battery, since it did not glow extremely brightly. All tests were done with the lead just wrapped around the resistor lead, and since the leads were poorly stripped, any results would have been unreliable. Since I was working with so many unknowns, I didn’t want to do anything hard to reverse. Many lessons learned here!  I look forward to putting the lessons to use.

Thanks,

Bruce

[BruceG]

Igor, IT'S ALIVE!  Not pretty, but functional.  IMO not bad for 75 year old hands and eyes.  I'm glad I did it instead of having someone do it for me.  Of course, I couldn't have without the expertise and help from @peteski. He even did a "proof of concept" project, and supplied me with some resistors.  Max Magliaro also offered some useful advice.  Many thanks to both!

Here's a low quality iPhone photo just for documentation.  I know the car is a foobie; I'm just going for a reasonably realistic model of an observation car.  Prototypical accuracy would be nice, but isn't essential for me.

[Lemosteam]

Looks nice, reminds me of....




Christmas!

[peteski]

Igor, IT'S ALIVE!  Not pretty, but functional.  IMO not bad for 75 year old hands and eyes.  I'm glad I did it instead of having someone do it for me.  Of course, I couldn't have without the expertise and help from @peteski. He even did a "proof of concept" project, and supplied me with some resistors.  Max Magliaro also offered some useful advice.  Many thanks to both!

Here's a low quality iPhone photo just for documentation.  I know the car is a foobie; I'm just going for a reasonably realistic model of an observation car.  Prototypical accuracy would be nice, but isn't essential for me.

The car looks great Bruce!  The photo is not too shabby either.
My friend is about your age and he still does some fine work (like installing decoders and detailing his models).  Nice to see you come out of your comfort zone and try something new. One is never too old to try doing something new. I also agree that the Railwire members are a very helpful bunch (when we aren't focusing on off-topic stuff). 

[mmagliaro]

I think it looks great!  I like both the color and the brightness.   And good on ya for persevering and seeing it through until you got it to work.  That's one of the best things about a project.

[BruceG]

Thanks for the compliments.  The bare LED was too bright, so I added a thin coat of transparent red paint to dim it down a bit.  In person, it is more solid bright red, without the almost white highlight in the photo.  BTW, the stock batteries lasted about 5 hours, then began to dim.  I look forward to @peteski's article on track powering.  Lighting a ten car train will get expensive, although those without the extra LED might last a little longer.

[peteski]

Thanks for the compliments.  The bare LED was too bright, so I added a thin coat of transparent red paint to dim it down a bit.  In person, it is more solid bright red, without the almost white highlight in the photo.  BTW, the stock batteries lasted about 5 hours, then began to dim.  I look forward to @peteski's article on track powering.  Lighting a ten car train will get expensive, although those without the extra LED might last a little longer.

I'll get that article finished one of these days  . . .   

As far as the LED hainvg a white highlight in the photo,it is quite a common problem. The LED chip which emits the light is so small and the light is so intense in that small area that it overloads the camera's image sensor, resulting in a white spot.