Hi, I'm working on making a simple rain alarm for kicks, but instead of using an 1N4001 diode I want to swap it out for an LED, the only problem is I'm not entirely sure how to find an LED that would have the same specs as the 1N4001. I've tried a few searches but so far I've only been linked to each one's individual specs, and thus I haven't found one that would be similar enough to be used instead of the 1N4001.
Most LEDs have a forward drop of 2-3.5V vs only 0.65V for a 1n400x at 20mA. The reverse breakdown of an LED is ~5V vs tens to hundreds of V for a 1n400x.
I assume that the LED you want to use is to indicate that the relay is activated. The diode is there short out the counter EMF from the collapsing field of deactivating coil, protecting the output transistors in the 555. Even if the LED could withstand the counter EMF current and voltage levels, it would have to be oriented in a manner that would not allow it to light. If you need an indicator, place the LED with a series resistor across the coil, with the anode toward the + supply.