Turntable remote operation

[abhi1981]

Hello
I have a Yamaha TT400U RS turntable which has a remote start/stop feature. The remote terminal is a 3.5mm mono jack, which activates a 12v solenoid plunger. The plunger mimics the function of the start/stop button. I don't have a matching amplifier with remote output. I tested it by manually feeding a 12v pulse to it and it worked perfectly. The first 12v pulse will drop the tone arm and another 12v pulse will lift the tone arm and stop playback.

Just for fun, I am planning to use this feature with an Alexa smart plug. So, I want to make a circuit which will send a 12v pulse when the mains power is on and another pulse when mains is switched off. I will say "Alexa, drop my needle" and playback will start ( just like Tony Stark in Iron Man 3)
Please help me with the circuit design. I'm a newbie when it comes to designing circuits.