Question for Jward re: installing directional lighting on HO GP60

[jbrock27]

Yes Jeff, I did see when I was at the store, that they had other resistors in the 500 range. 
My plan is exactly what you suggested-to check the brightness I get before finalizing things.  What I am going to do is temporarily tape a resistor to a leg of an LED and see what kind of brightness I get with the 680 by connecting to the DC on the MRC Tech II 1400 power pack.

The resistors were very inexpensive=$1.19 for a packet of 5.  I figure if I need to change to a lesser Ohm value to get the brightness I like, it is not a big investment of $$.

What do you think if my idea in my post just prior to my last one?  Does that sound like a good way to test which "direction" the LEDs will turn on, before I "sock" everything in on my loco?

Thanks.

[jward]

it doesn't matter which leg the resistor is on. the resistor is not polarity sensitive, but the led is. if you intend on soldering the resistors to the brass bar you mentioned, then i can see doing that to help keep things straight in your head.

one final note. i haven't bought a newer athearn but i cal tell you from experience that the old blue box frames were almost impossible to solder to. what i ended up doing was tp drill and tap the frame for a brass screw and solder any wire connections to the screw. i also recommend that if you intend on soldering anything to the motor contact strips that you carefully remove them from the motor before you solder to them. there is a brush and spring beneath these strips and if you are not careful the spring goes flying.

[jbrock27]

Thank you very much for getting back to me

Yes I remember you telling me it did not matter which leg to put the resistor on.  Yes I intend to eventually solder the legs with the resistors soldered on them, to the brass bar.

What I was going to try first, was to touch an LED (which a resister attached to one leg) to the DC contacts on the power pack.  Put the power on, turn the dial, lets say halfway at first.  If it does not light, then I will switch the "reverse switch" on the pack to see if the LED lights then and do the opposite with the other LED.  The only thing I learned from Radio Shack's employee last night, is the long leg of the LED is the +.

Never planned to try to solder to the frame (see OP) but thanks for the reminder.  When I take the copper contacts off, I usually put some sort of box (like clear plastic) over what I am doing, in the event the springs go flying.  The box has a better chance of catching them and me finding them.  So far, so good.

Yes, I always solder with the contacts off the motor.  Along those lines, I don't solder wires directly to the tops of the trucks either.  I buy those clips (can't recall the name right now) that you can find at Radio Shack.  I solder wire to that and then slide the clip onto the truck.  This way I can work on the trucks if I have to, without having to "de solder".     

[jbrock27]

...I also trim the motor springs about 1/3 to help with low speed running.

With regard to the "newer" Athearns, I just bought a brand new Athearn Ready to Roll (CSX-very cool).  They are not as advanced as the Genisis Series (I always think of Wrath of Khan when I hear 'Genisis").
The RTR have many similarities to the old BBs.  Same silver motor clip at top that touches the 'welder in the cab bulb', bronze bushings like later BBs and gold can motor.  Much of everyhing is the same as BBs.  Except, the flywheels have hex connector for the drive shafts and the shell is very nicely detailed.

My project GP60 (see OP) is an old BB and if it works, will try with other nicer models.

[jbrock27]

**A note**

On test, the brightness seems good with the 680.  Not too bright but much 'cleaner' light than the incandescent bulb that's in there.  I don't have a greater value resistor to try to compare.
Also, throwing the direction switch on the power pack is a good indicator of when the LED will go on & off, to help with set up of which LED to put at which end.

[jward]

glad to hear it's working well for you.

[jbrock27]

Yea, way cool!

I then tried two 680s in series to see what would happen to the brightness (I don't have any other  resistors on hand) and the LED would not light.  So 680 is probably what it is going to be.

[jward]

1360 ohms put the voltage below the threshold for the led. so you're probably looking at about a 10 milliamp rating for the led?

[jbrock27]

I would like to say a thank you to Les (Desertdweller) and Jeff (jward) for their help with this project which I finally got around to yesterday. 
I am very pleased with the results.  Thank you again guys.