I'm looking to add some lighting to my existing trackside buildings, so I can run at night time, with a sense of realism. what do folks use for the job ? Batteries, 12 v dc feed from controller etc, LED's, grain of wheat bulbs etc.
Also, has anyone been able to mimic the "flicker" of older gas lights, and if so, how ?
For older gas or tungsten-lit buildings I put 2 minature 12 volt bulbs in series and run them off the AC accessory terminals. An alternative would be to use yellow LEDs.
I wasn't aware that gas lights with mantles flickered, except perhaps in a high wind (or draught). I guess very old open-flame gas or paraffin lamps would flicker more.
Phil: This christmas, Strings of White LED lamps were available very cheaply - 80 for 10ukp with transformer. Or if separated, choose suitable resistors to limit the individual (dc) current to 10mA per LED (V=IR) and allow for 2-4V across an LED according to colur etc. NEVER use an LED from a voltage source (eg battery/power supply) without a current limiting resistor or similar protection, of course.
Not quite true, if you arrange for the correct voltage to be supplied, you don't need a resistor.
Andrew
Phil: If you were then to replace the LED, with one of a slightly different Specification, the voltage drop across it would change, and this would result in a very different current (and brightness). The CURRENT is what you wish to control (/limit), and unless feeding from a current source, it is advisable to ensure a minimal variation - eg with a series resistor. A voltage source (as I specified above) is not suitable without the extra protection - eg the variation of voltage from a battery / internal resistance during its life, or with a (regulated) theoretical power supply - an infinite current availability at the specified constant voltage - (subject only to the constraints of Ohms law on the total load - and the LED is non linear)
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