The Hy Power GU4-HF-5KWA is a 4:1 Guanella Current HF Balun with an SO239 connector for coupling your coax and machine screws for connecting parallel feeders or your antenna wire. These baluns maintain a flat SWR curve over the entire HF frequency range when terminated into a 200 ohm matched load.
Model version "A" is designed to be used at the feed point of your antenna, such as a folded dipole or any other 200 ohm antenna. It can also be used at the shack end of your parallel feeders. Both the version "A" and the version "S" use the same internal parts and can be interchanged.
The Hy Power GU4-HF-5KWS version "S" does not have any eye hooks and the terminals for your parallel feeders are on the top of the enclosure instead of on the sides.
These are very efficient baluns that are better than 98% efficient from 160 to 6 meters. It uses dual ferrite cores and can handle 5KW continuous and up to 10KW peaks in a matched condition. The dielectric of the wire in conjunction with the teflon tubing gives the balun a voltage rating of 10,000 volts. These ratings are good up to a 2:1 SWR.
The balun is built inside a NEMA enclosure and will stand up in a harsh UV environment. The hardware is also stainless steel so will not rust! There are also two drain holes in the bottom of the enclosure should any water work its way inside.
If the balun is mounted vertically, coax connector aiming down, the enclosure is considered water resistant and no additional protection is needed. If the balun is placed on a flat surface and no additional protection against the elements are provided, the bottom half of the enclosure could possibly fill with water over an extended period of time. It is suggested that the balun be placed inside a waterproof enclosure. The "S" model has two extra drain holes so this problem does not happen, but it is still a good idea to provide an extra waterproof enclosure.
This is an ideal balun to be used on an Off Center Fed Antenna.