I can't check now, but I think the tesla coil relies on a lot of integrated devices. Integrated devices can be looted from some Academy troops and by building them from space electronics. Disassembling items mentioned above is a great way to get space electronics, until the player has the research and funds to buy them from the black market.
Also disassembling slave AIs is also a great source of space electronics I find. Loot every shipping you can get your hands on, in other words.