But before we can precede, we need to know EXACTLY the LENGTHS of each Section of the Zig-Zag Structure including the outer Section LENGTH and ORIENTATION....as well as the Overall LENGTH of the Reflector Rods incl. the size of the Mid-Point GAP....and the Reflector-to-Bowtie Separation....and lengths/orientation of whatever other filligree that might have been added onto the Original Hoverman....if your's doesn't EXACTLY MATCH one of the following, please post some pictures.
Doyt R. Hoverman's original design for a television antenna was granted US patents #2918672 on 22 Dec 1959 and #3148371 on 8 Sept 1964.
The Hoverman [and later SBGH] was based on Henri Chireix's earlier Patent [12Apr1928] for a Totally Symmetric "4-Square" [i.e. 4-Segment] Zig-Zag Antenna in which ALL Segments are the same Length (7-in) at exactly 45-deg Angles, including the outside "Zag's" which turned back around towards the middle, also at 45-deg Angle. It was determined that the Optimum Segment Length was between 10.0 to 10.2-inches, which provided higher Gain than a Hoverman, but at the expense of Gain Roll-off due to narrower Bandwidth:
UHF Chireix Antennas (NO Reflector)
In Doyt Hoverman's Type-1 Hoverman Antenna, ALL of the Dimensions were SMALLER (only 7-in), also with 45-deg Angles, except he ROTATED the Top and Bottom Segments HORIZONTALLY OUTWARD (also 7-inches), as analyzed here:
Hoverman Type1 (NO Reflector)
Hoverman Type-2 was identical, except FOUR Reflector-Rods were added, with a Mid-Point Gap, as analyzed here:
Hoverman Type 2 w 4 RRs - Doyt's
But the Radio Shack R-S 15-1627 continued to use 7-in Zig-Zags, except they actually reverted BACK to the CHIREIX design, with the Top & Bottom Z-Z Segments pointing OUTWARD at a 45-deg Angle [5.4-in plus 1.0 in Vertical Spur]. They ALSO ADDED some Short Vertical Stubs at the Top and Bottom, probably to adjust SWR rather than improve Gain. I posted analysis here:
Hoverman Type 2 w 4 RRs - Radio Shack
First of all, we need you to verify whether or NOT what you have is truly the R-S 15-1627 as depicted in fol. 1971 Allied R-S Catalog:
1971 Allied Radio Shack Catalog Low-res page 292 of 464
If so, carefully verify that it TRULY has the fol. Dimensions (taken from the 4nec2 File cited above):
CM Length of each Diagonal sub-section = 7 inches, Gap at Feedpont = 1.5 inches.
CM Split Rod Reflectors with Center Gap of 1.5 inches and with the following OVERALL Lengths:
CM - Top and Bottom = 14" + 1.5" + 14" = 29.5"
CM - Middle = 10" + 1.5" + 10" = 21.5"
CM - Reflector-to-Bowtie Spacing = 4 inches
Note that I posted a photo: "HOVERMOON" of my similar, yet slightly DIFFERENT Hoverman...let us know if you have THIS Variation.....I have the Dimensions but have not yet posted 4nec2 Results....it's still hanging in my Garage.
One of the original SBGH's [e.g. Autofils Version] increased all 45-degree Angle Zig-Zag Lengths from 7.0 to 7.07-inches (negligible difference) and more importantly changed Horizontal Stub Length from 7.0 to 5.0-inches. This improved overall Gain, as well as extended it to include Ch51 by SHORTENING the Horizontal Stubs:
Antennacraft G-1483 Hoverman Type 2