Let's see if I can answer some questions for you:
1a. Wi-fi: I only use this for Skype sessions now. I have my networked computers connected using Ethernet cables. Electrically, wi-fi doesn't interfere with any transmission mode. However, the frequencies chosen by the regulatory "authorities" are now known to be deleterious to health.
1b. TV: Electrically, this doesn't interfere with either Contact or Remote Mode. However, Plasma Mode will disrupt its reception, usually making it unwatchable, but the TV won't affect Spooky Central.
1c. PC: Doesn't interfere with Contact or Remote. Plasma may affect its operation, but the PC won't affect plasma.
1d. Cell phones: even when they're turned off, these emit a powerful microwave signal burst looking for the nearest tower every 15 seconds. The idea is that you will have instant connectivity when you turn the phone back on. The only way to stop this is to remove the battery. Although they don't affect Spooky equipment, our advice is to remove them from the room. I no longer use my iPhone.
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