Mark Gurries
solution for dimming headlights for decoders that don’t have Dim feature.
>My
query is how do I get locomotive headlights to dip/dim via any of the hand pieces? I am
using White LED's and new to >using DCC. Thank You Kevin Bush(
Two solutions.
1)
Use a FX decoder that support Rule 17 (dimming) and LEDs
based light effects. NCE's
decoders do that.
2)
Build your own dimming circuit with resistors and a
extra standard function output. One
function turn on the LED through a 2nd series resistor R2 making it dim, while
pressing the other bypass the R2 resistor restoring full brightness. R1 does not change it value as it sets the
current for the LED when operating a normal full brightness.
The
value or R2 will be experimental based on the "dimness" you want.
Blue---/\/\/--|>|--+---/\/\/----F1
R1
LED | R2
+------------FF0 (F0)
Best
Regards,
Mark
Gurries
Linear
Technology
Power
Supply & Battery Charger Applications Engineer/Manager
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Model
Railroad Club and NMRA DCC presentations are at:
http://www.siliconvalleylines.com/index.html