All the MHD generator units have been broken down. We’re building them back up with smaller tiles. The large tiles tend to crack under the high thermal shock. The smaller tiles should be able to expanding and contract.
One generator will be for the ‘D’ and ‘E’ motors with the Faraday configuration. This will let us start to get a electrical power to thrust curve (we have the ‘C’ data). The other unit will use the small motors and be set up in a Hall effect configuration. I expect twenty or so firings before we see our first electron.
This is the sort of primary research that NASA should have been doing for the last 40 years.