The low band monopoles use the folded monopole design to create an electrical mirror image dipole element in the ground screen. The wire elements futher augment this electrically. Height is between one eighth wave lengths at 2 mhz and about a half wave a 9 mhz. Impedance is between 10 and 30 ohms. The high band monopoles also achieves the high Q goal and also uses the mirror image to create a dipole electrically.
Similar impedance is likely.
This is all I could glean related to actual construction details. The dimensions are not likely to be exact. Monopole designs are derived from surplus monopole antennas described by others. Scales are from photographs. The Wullenweber's days may be numbered.