vintage Linear security systems

I am making this topic because I cant find any information at all online about these, but I still see them everywhere.

My grandparents had a big Linear wireless security system. It was put in in 1990. In 2016, they had the panel removed, and I took it apart. All I have left of it is the backup battery. 2 years later, they gave me a bunch of the wireless transmitters connected to magnet switches and one motion sensor. The modules looked like this:[attachment=0]s-l640 (1).jpg[/attachment]
The motion sensor was a big rectangular thing with an off-center square window on the top. It had a small lithium battery inside. If anyone can give me a model number, please do. Anyway, I took those apart too. The modules at her house had an oscillator chip to create the rf signal.

Three modules remain at their house, connected to magnet switches and one plunger switch. Next time I am there, I will have to ask for them.

Good news: I recently was at their house, to find that there were still a lot of transmitters there, as well as one remaining motion sensor. I felt very good taking those home. Pictures coming soon.

There’s a Subway near my house that has a Linear system. I guess SafeTouch put these in as well as DSC systems. Too lazy to google pictures and haven’t taken pictures of the Subway system, because Subway is small and taking pictures is weird.