Laryn, There is only a couple of things you need to do with DB antennas, one is tighten ALL screws everywhere, especially on new antennas! The second is put about three coats of 3M Scotchcoat on every junction including the coax connectors, follow the instructions in next sentence for the connectors. Don't use their tar sealer use only Scotch 33 tape, put one layer on real tight, coat with Scotchcoat and wait a few minutes until tacky. Then layer another wrap of Scotch 33 tape and coat that with two layers of Scotchcoat.
I have an DB-410 antenna I installed in 1976 or so, it's still being used, I have to admit I took it down in 1988 or so and slapped some more Scotchcoat on it for good measure though. Lloyd Alcorn, Kit Parsons and Ray Trott did a great job designing those antennas, not much can be done to improve it. Paul WB5IDM -----Original Message----- From: Laryn Lohman [mailto:[EMAIL PROTECTED] Sent: Tuesday, January 13, 2004 9:28 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: Adding "whiskers" to a DB-224? Derek, my concern is mechanical, rather than RF. Many moons ago, I received a brand new DB224 for the club, which was soon to be installed at a new site. Observing the fine new aluminum elements, I saw that the drain hole was not in the bottom of the loop, but rather up an inch or two from the bottom. My infallible wisdom dictated that a drain hole should be at the bottom. So, I made it so. A year or two later we were getting a lot of noise on some signals on the repeater. Inspection revealed that three of the four dipoles had physically broken, you guessed where, right where I had drilled the small drain holes. :( Having said all that, filling the hole with a good stainless bolt like you did may prevent that kind of mechanical failure, I don't know. There are apparently stresses and fatigue going on there that I don't fully understand.... Laryn K8TVZ --- In Repeater-Builder@yahoogroups.com, "Derek B. McIntyre" <[EMAIL PROTECTED]> wrote: > I have heard that adding whiskers to a DB-224 element > > Derek KC4FWC Yahoo! Groups Links To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ To unsubscribe from this group, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/ Yahoo! Groups Links To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ To unsubscribe from this group, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
