Hi all, Today I added flashing LED ditch lights to an Athearn N scale F59PHI. The decoder manual recommends lamps, but I used LEDs for space reasons and heat concerns. I used 1500 ohm resistors. CV51 is set to 106, CV52 is set to 107, CV63 is 64, and CV62 is 00. When I hit F2, they do flash, but just barely. Is there any way to make the "dim" phase dimmer? Or will I have to convert to grain-of-wheat bulbs?
I would suggest using a lower ohm resistor. The high resistance you are using isn't allowing the LED to come to full brightness which is why they don't look like they are really flashing. Normally with LED's 1000 ohms is more then enough to keep them in their safe zone but every LED is different and depending on the specs determins the size needed. I've used as low as 330 ohms.
It's possible you have the same problem as the Soundtraxx LC (Low Cost) decoders - also not LED friendly. Eagleman posted a diagram of a fix for that in this thread last year: http://www.trainboard.com/grapevine/showthread.php?t=76836&highlight=blinking (If that link doesn't work do a search for "Blinking LED" and you should find a similarly named thread.) Trouble is, from what you said you probably won't have enough space to fit all the components in
Interesting circuit! However, I think I'll just switch to bulbs for this loco. The next issue will be my B23, which is loaded with lighting effects. I see no way I can switch it to bulbs, and no room for a capacitor circuit. I guess I'll deal with non-flashing ditch lights on it, and I've never seen a prototype Gyralite in action, so that effect looks okay to me
I managed to get a video of my ditch lights sort-of-flashing. It also shows big problem #2- the ditch lights are about 10 times brighter than the headlight. I still need to tweak my resistors a bit. http://www.trainboard.com/railimages/data/500/DSCN1482.MOV
The circuit for the blinking LED's with Soundtraxx decoders will not help your situation. That circuit is for LED's' that DO blink when they are NOT supposed. I just installed blinking ditch lights in my Kato P42 using grain of wheat bulbs. The problem I had is the headlight fills the area where the bulbs are with so much light that the ditch lights look like they are constantly lit. Since your headlight does not appear to be as bright, I wonder if the two ditch lights are flooding each other out so that the one that is lit is causing the one that is not lit to look like it is. On mine I am adding some black dense foam to the interior and painting the sides of the light pipes to block the lilght from the headlight. So far it has helped a lot, but I still need to do some more work to get it to look right.
That isn't quite correct (from my own experience with a Soundtraxx LC). What actually happens is that when the loco is running forward the rear headlight LED sometimes lights at about 50% brightness. (And when running backward the front headlight sometimes lights.) The 'sometimes' appears to be on alternate speed steps, so as you accelerate the engine the LED goes off-half-off-half, which is sort of blinking, but if you leave it at a given speed it just glows or doesn't. I can't imagine how they managed to achieve this ... accidentally I hope The resistor/capacitor mod circuit is supposed to cure this, presumably by reducing the glow to an invisible level. The problem jwaldo describes ("they do flash, but just barely. Is there any way to make the "dim" phase dimmer?") sounds as though the ditchlights are going on correctly, but are still glowing when 'off', which will make them not appear to flash properly due to the lack of contrast. The mod circuit might improve that by allowing them to switch off fully.
