Got a Sirio 827 with broken radials? Got a 827 that's gone open circuit? Fear not, there is life in the old beast. I've taken an 827, removed the matching coil and turned it into an half wave dipole. Basically, removed the radials and matching coil and set the element length at 17 feet to begin with. Cut it in half and added a piece of fiberglass between the two elements and epoxied it into place with an inch gap. Drilled an hole at the base of the lower element near where it connects to the coil former and fed the coax inside the lower element up to the feed point where i'd drilled an hole in each element at the feed and pulled the centre feed through the upper element hole and the braid through the lower element hole. Bolted the feeds to the elements with stainless steel bolts. It took 20 minutes to tune and each element was at 98 inch when it tuned at 1.1:1 at my centre frequency of 27.78 megs. It tuned to 1.3:1 at 27.4 megs and the same at 28.5 megs so pretty wide banded. The good news is the 827 is already isolated at the base with its built in fiberglass isolating tube underneath the coil former. I used a TDK 61 mix ferrite level with the base of the lower element to choke the coax from the antenna. Works excellent and is basically the same design as a Gainmaster half wave. Good radio reports too so far. I've named it the Split27.
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