Is this possible? Or another ways to set off car alarms (without brute force or noises) perhaps with two way radio?
i dont think it would be possible to set off an alarm with IR as i have never seen an alarm system with optics. they can and are turned on and off with radio signals. however you would need to know the frequency, modulation type (probably phase modulation) and code information (ie for pm devices the number and timing of the pulses) for any particular vehicle alarm. also any particular brand and model of alarm will differ from one unit to the next. that is the exact same alarm system will come with varying programed keys so that 2 identical units will use different codes so that your next door neighbors keychain remote will not operate your alarm. but if you know all the information needed you could make a device that would operate someone's alarm.
Not any decent car alarm it's not. maybe some off brand that you pick up for 39.99. IR is light spectrum,so No. and it would have to be one hella strong radio signal to overpower the electronics in a car alarm. Years ago it may have been possible today,not so much.
particular, that is called Panic, Panic Mode, or something to that result. in the journey that your automobile's alarm gadget is provided with it, there will be a button for it on the distant (could be a purple button with a horn making noise/an asterisk/merely the be conscious Panic. relies upon on the gadget, particularly). merely press the button and lean decrease back.