Folks, I need to replace the LED in this MTL FT. I touched a new LED to the solder point, and it lights. But what is the brownish bit soldered across the legs? If it doesn't survive my solder job, is there a larger (more easily manipulated component, I can substitute? I don't think it's the resistor, because I thought that sits in series and is the little block, along the trace, seen below Sent from my iPhone using Tapatalk
The brownish thingy is the bias resistor for the LED and should be left alone. Just replace the LED and observe the polarity that lights it.
It looks like a ceramic capacitor to me? The current limiting resistor for the LED is in series with the LED and can be seen at the top of the photo (marked 102 = 1K ohm). Without seeing the rest of the circuit board it is difficult to know what the function of the capacitor and diode accross the LED is. If you're not confident with soldering the board, to save disturbing the capacitor, it may be better to cut the LED leads about halfway along and then solder the replacement LED to the stubs.... Jim
The "brownish bit soldered across the legs" of the LED is a surface-mount ceramic chip capacitor used to prevent flickering of the LED caused by the BEMF from the motor. It's a very common type of part and replacements are readily available, if needed.
Thanks folks So that means, it can come out, if I found the issue, preparing to install hard wired DCC. The headlight voltage should be isolated, from any motor effects. Correct? Sent from my iPhone using Tapatalk
