Neon sign transformers are routinely the cause of such interference as well: https://www.schneier.com/blog/archives/2016/08/unintentional_d.html https://www.sc

Neon sign transformers are routinely the cause of such interference as well: https://www.schneier.com/blog/archives/2016/08/unintentional_d.html https://www.schneier.com/blog/archives/2016/08/unintentional...