Oh yeah, $189 for such a simple feature. It is more expensive than a transformer.
I made such things cheaply 30-40 years ago and they still work everywhere. My brother's amplifier has one of the first inrush current limiters I built as a student. And it's still in operation every day in his workshop. I did a recap about 10 years ago.

I made such things cheaply 30-40 years ago and they still work everywhere. My brother's amplifier has one of the first inrush current limiters I built as a student. And it's still in operation every day in his workshop. I did a recap about 10 years ago.
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i thought a while about it and i think i will do this:
- screwterminals for: 1.power IN/OUT 2. external resistor IN/OUT 3. button IN/OUT 4. led +/-
the thing should work something like this:
(on standby maybe led breathing or something like that)
you hit the switch, the microcontroller closes the resistor relay, waits 3-5 seconds and blinks the led, switches the passtrough relay and makes the led steady, a 1second press turns the device off
maybe its also possible to reserve 1 or 2 gpios for external functions i dont know yet
i think putting all together is quite simple but i have to see, the arduino program for the microcontroller should be no problem
- small transformer with rectifier and smoothing caps
- one 5V regulator socket for my tps regulator
- atiny10 microchip
- 2 relais, one as passtrough and one to switch the resistor trace off, making it possible to actually switch ON/OFF
- screwterminals for: 1.power IN/OUT 2. external resistor IN/OUT 3. button IN/OUT 4. led +/-
the thing should work something like this:
(on standby maybe led breathing or something like that)
you hit the switch, the microcontroller closes the resistor relay, waits 3-5 seconds and blinks the led, switches the passtrough relay and makes the led steady, a 1second press turns the device off
maybe its also possible to reserve 1 or 2 gpios for external functions i dont know yet
i think putting all together is quite simple but i have to see, the arduino program for the microcontroller should be no problem