--- In [email protected], "Dave Baughn" <[EMAIL PROTECTED]> wrote: > > Does anyone know if there is any science behind the location of the weep > holes in a DB224 element? I have had several crack at the very bottom, > apparently due to freezing water inside.
I don't necessarily know about the science behind the location of the holes, and sure, it seems like water freezing has cracked your dipoles. But <once> I thought I was smarter than DB Products. I received the shipment of a brand new DB224 some years ago for our club repeater. Yup, there were the holes, nowhere near the bottom where water collects. So, out comes the drill, and holes about 1/8" diameter appeared dead-bottom-center in each dipole. Some months later, (it wasn't even several years) the dreaded <antenna noise> bugs were being heard. An inspection of the dipoles discovered 3 of the 4 dipoles had cracks or were completely broken at the bottom, right through the holes I had drilled. <sigh> I called DB and was told that the bottom of the dipoles is a "high stress" point therefore that's why the holes are not drilled there. I no longer re-engineer dipoles. Having said all that, I also have a ASPB602, the Antenna Specialists version of above 4-dipole antenna. Those dipoles are 3/4" OD, as opposed to DB224s at 3/8" OD. The drain holes are factory supplied directly at the bottom. Go figure. Laryn K8TVZ
