I'm sorry, but your first sentence seems garbled, and I can't understand your point. Hardtack II was conducted at low altitudes (4,000-6,000 feet) with only 4 larger than 1 kt yield. They were squeezing in a bunch of tests of new designs, but it doesn't seem that EMP effects were high on the list of properties to be concerned about. https://en.wikipedia.org/wiki/Operation_Hardtack_II
I'm sorry, but your first sentence seems garbled, and I can't understand your point. Hardtack II was conducted at low altitudes (4,000-6,000 feet) with only 4 larger than 1 kt yield. They were squeezing in a bunch of tests of new designs, but it doesn't seem that EMP effects were high on the list of properties to be concerned about. https://en.wikipedia.org/wiki/Operation_Hardtack_II