Model Railroading > LokSound Select Micro Question

I am preparing to install LokSound Select Micros into two Athearn RTR SD 40-2s. I know I can plug the micros directly into Athearns light board, but I want to swap out the Athearn bulbs with Miniatronics 1.5v bulbs. I also want to add a rotating beacon to both units. Can I use the same 1.5v bulbs on the decoder accessory outputs as well?

John

The LokSound Micro does not have resistor protection for bulbs (or LEDs) built-in. I would recommend LEDs over Miniatronics bulbs but if you are set on bulbs, I used to use a 390 ohm 1/2 watt with the 30ma bulbs. If you use the 15ma bulbs, you'll want a 680 ohm resistor. Each bulb needs it's own resistor. My disclaimer here is that I haven't used bulbs in some time so these values may need to be adjusted a bit.

If you decide to use LEDs, a 1k ohm 1/4 watt resistor per LED works great.

Lee Ryan - Rio Grande Fan
Denver, CO

There are 1.5 v bulbs on the Athearn light board. If you plug the loc sound decoder into the light board then the headlights will work with 1.5 v bulbs.

You will note a solder point near where the green wire from the 9 pin socket goes into the light board. You can use this for a rotary beacon. It's output is 16 v so you will need to put a resistor into the circuit for 1.5 v bulbs. Sometimes there is a clearly marked + or blue for the function return. This has evolved on various generations of the light boards so you will have to poke around somewhat to work it all out.

I have done this on some of my Athearn rtr units with great success.

Posted from Windows Phone OS 7

http://www.esu.eu/en/products/loksound/loksound-select-micro/

This decoder will not "plug" into the Athearn board. You can get the loksound select "direct" which REPLACES the Athearn board and has the Loksound Select Micro built into the same size board. However, you'll need to add resistors for the 1.5v bulbs.

Lee-
do you have a source for LEDs and resistors? I would prefer to use small surface mount resistors instead of the lead type. I had a Lok Sound Select Direct in my first SD40-2, but I broke the circuit board leads on the back, due the the resistors. I think to simplify the installation, I will use the select micros on the SD40-2s and stuff the damaged select direct into a F7.

Thanks,
John



RioGrandeFan Wrote:
-------------------------------------------------------
> The LokSound Micro does not have resistor
> protection for bulbs (or LEDs) built-in. I would
> recommend LEDs over Miniatronics bulbs but if you
> are set on bulbs, I used to use a 390 ohm 1/2 watt
> with the 30ma bulbs. If you use the 15ma bulbs,
> you'll want a 680 ohm resistor. Each bulb needs
> it's own resistor. My disclaimer here is that I
> haven't used bulbs in some time so these values
> may need to be adjusted a bit.
>
> If you decide to use LEDs, a 1k ohm 1/4 watt
> resistor per LED works great.
>
> Lee Ryan - Rio Grande Fan
> Denver, CO

The lok sound micro has an NMRA 8 pin plug as part of the wiring harness. The Athearn light boards have the 8 pin socket as well as the 9 pin JST connection.

Plug in the decoder to the NMRA socket and the Athearn factory 1.5 v bulbs will be protected. You will have extra wires for the green and purple functions as well as the speaker. If you use the green wire for the rotary beacon you will have to hard wire in a resistor. You can also use the lok sound replacement board but I have no idea about the lighting outputs. You may have to hardwire resistors or change the Athearn bulbs.

Let us know how it works out.

Posted from Windows Phone OS 7

"do you have a source for LEDs and resistors? I would prefer to use small surface mount resistors instead of the lead type."

Walthers carries the Ngineering line of components where you will find small leds and an assortment of surface mount resistors.

Posted from Windows Phone OS 7