28 GHz Gyrotron ECRH Upgrade for LDX

A 10 kW, CW, 28 GHz gyrotron is being implemented on LDX to increase the plasma density and to more fully explore the potential of high beta plasma stability in a dipole magnetic configuration. Higher density increases the heating of ions by thermal equilibration and allows for improved wave propagation in planned ICRF experiments. This represents over a 50{\%} increase in the 17 kW ECRH from sources at 2.45, 6.4, and 10.5 GHz. The higher frequency will also make possible access to plasma densities of up to 10$^{13}$ cm$^{-3}$. The 1 Tesla resonances are located above and below the floating coil near the dipole axial region. The gyrotron beam will be transmitted in TE$_{01}$ mode in 32.5 mm diameter guide using one 90\r{ } bend and a short $<$ 5 m straight waveguide run. A Vlasov launch antenna in LDX will direct the beam to the upper 1~Tesla resonance region. A layout of the planned system will be presented.