I know I have read where the headlight bulbs in Genesis F units burn out quickly on DCC and need to be replaced with LEDs. However, I will be running DC for a while and I was wondering how long they last on analog systems or do they still burn out quickly. Thanks
The longevity of the Genesis 1.5 Volt bulbs doesn’t seem to be related to whether they are running on DC or DCC. With a proper resistor, or a decoder with a built-in voltage regulator for the bulb, they may actually last longer on DCC than DC because you can run with them turned off if you want. The biggest problem seems to be that they are not very good bulbs to begin with.
If wired up properly, and LED will live longer than the locomotive. They are good for about 100,000 + hours. If your F7 has the four headlight setup, you are going to need surface mount 603’s in order to fit all of them inside the bezels. Two headlight, or one headlight would use the 3mm leds.
I had a light in my MILW F9 burn out a year ago. I called Athearn for a replacement, and they could either send me one, or I could send the engine in to get it installed. I installed it myself.
Tha pain-in-the-butt about it was the wiring through the interior, and getting the interior to fit properly again (arrgh!). I eventually got it working again.
I have never heard anything about them running out better on DC vs.DCC (I am a DC user), but I’m sure some electronic DCC junkie out there might have a reasoning (if any).
Phil
There are three bulb situations with Genesis F-Units; one is some modelers have installed “plug and play” decoders they assumed had the proper current limiting for the stock bulbs and they burn out almost immediately. The second situation is related to the bulb itself; the filaments are known to prematurely fail - DC or DCC. The third is DCC related; some modelers have used resistor values that operate the bulb at the bulbs rated current. However the risk of burnout is high if the bulb’s turn on current is not gradually applied; the inrush of current at startup is higher when the bulb is cool than when it is hot. This can cause some failure.
On DC, resistors only are not used in Genesis locomotives as current limiters; a voltage regulator is made from diodes either placed in series or 4 diodes in a bridge. The bridge allows bulbs to light in either direction (two for forward, two for reverse). A ballast resistor is placed in series with the diodes to limit the current flowing through them. The voltage drop across each diode is 0.6 volts; hence, 0.6 V + 0.6 V = 1.2 Volts; close enough to the 1.5 volt rating to give adequate light while limiting the current to approximately 10 milliamps as opposed to the rated current of 12 milliamps. Doesn’t seem like much, but it is significant in the life expectancy of the bulb.
On burnout, some people replace them with Miniatronics 1.5 Volt, 15 ma equivalents. Again the current is limited to below rated values; 12 ma as opposed to 15 ma.
FOR DCC USERS: I recommend using voltage regulators LM317LZ, available from Digikey, Mouser, All Electronics and other suppliers. One regulator is used per bulb. Cost p
Does anyone know how to activate the red bulb (emergency brake indicator) in the upper housing on an Athearn DCC/Sound Santa Fe F3?
I’ve tried many different configurations and can never get it to light. Before I open it up to see how it is wired, if at all, I wondered if anyone here has had any luck with the red bulb.