Garage door receiver shorts its own power supply

You'll find that the sensors are fed from the main unit via current-limiting devices such that a heavy current draw causes a 1 ->

Something to keep a short from burning stuff up (see JT's comment), a big- ass cap to hold power during the "power off" interval, and flash memory.

Or, don't short it out completely -- just draw enough current to suck it down to 5V or so.

You don't need power available to "remember stuff".

Try this:

- install your receiver

- give it whatever "secret" it needs to remember

- SHORT the terminals to the receiver FOR A LONG TIME (seconds) [chances are, the GDO will either start opening when you first APPLY the short *or* when you remove it. But, probably won't REstart when the GD completely closes/opens -- i.e., it looks for the *transition* to start the mechanism]

- now try your receiver to see if it still "remembers".

Or, easier still: simulate a power failure by unplugging the GDO (which removes power to the receiver!) for MANY HOURS.

All you have to do is be able to create a "temporary short" that is long enough for the GDO to sense that fact. I.e., you need to have some energy stored "outside" the shorted system that will allow you to maintain the short (via a FET or transistor) for a long enough time to cause the GDO to notice it.

Electronic doorbells also do this (in a few different ways).