Doug, Ron, Corey and all, thanks for the suggestions on materials for the DB-224. Your suggestions were good and welcome.
73 JIM KA2AJH ----- Original Message ----- From: n3dab To: Repeater-Builder@yahoogroups.com Sent: Tuesday, June 24, 2008 3:14 PM Subject: Re: [Repeater-Builder] Reasonably low wind load antenna For anyone looking for a DB mast to mount their dipoles and harness on, check out all you commercial radio shops for damaged or pulled DB antennas. Don't worry about what band they are on - all you wan't is the mast anyway. DB's are sleeved internally at the center joint with exposed ends of the upper and lower mast sections being cut at a 45 degree angle. The sleeve is secured in the top mast section and slides into the bottom section about a foot. the top and bottom are secured together with 2 SS hose clamps. The base is also sleeved internally for clamp reinforcement. Another source would be a metal fabricator or aluminum supplier and purchase a 20' section of 1 3/4" 0r 2" heavywall aluminum tube and mount your dipoles on it. Wall thickness should be 1/8" thick minimum top to bottom. If you can also pick up a 24" long section of tube to slip up into the bottom to reinforce the clamping area all the better. Doug N3DAB --- In Repeater-Builder@yahoogroups.com, "Jim Cicirello" <[EMAIL PROTECTED]> wrote: > > Ron, > > Thanks for the mounting information. I also lack the DB224 Mast that the four dipoles mount on. From my research the original is two pieces about twelve feet long that I believe bolt together, the diameter I have not been able to find. From the ones I have seen the mounting pole is quite robust. Do you have any pole stock that you could recommend that would hold the DB224 on a side mount configuration? As I recall although the mast was very rigid, it was quite lightweight. > > Thanks JIM KA2AJH > > > > > > _____ > > From: Repeater-Builder@yahoogroups.com [mailto:Repeater- [EMAIL PROTECTED] On Behalf Of Ron Wright > Sent: Tuesday, June 24, 2008 12:23 PM > To: Repeater-Builder@yahoogroups.com > Subject: Re: Re: [Repeater-Builder] Reasonably low wind load antenna > > Jim, > > The DB224 is usually supplied with 2 clamps where each clamp attaches to the DB224 mast and the other side clamps to the tower/mounting pipe. I believe these are made for 2-1/2" pipe. > > At www.tessco.com you can see pictures of these clamps and also purchase them although they are not cheap. They are very rugged galvanized clamps with 3/8-1/2" bolts 8" or so long and nuts. > > I would recommend looking on e-bay or someone here that might have them. > > Another mount is side mounts. For DB224 18" off the tower is typical. These have V shaped pieces one at each end of 2 pipes. The V is clamped to the tower and the other end the DB224 is clamped. You really need 2 mounts for this, one at the bottom and one near the top. Usually the top mount is a single pipe with C/U clamps to keep the antenna from swaying and the bottom holds the antenna weight. > > The DB 224 can be top mounted without the fear of the swaying in the wind damaging it unlike fiberglass antennas. I like putting top and bottom mounts when one can, but if top mounted not done for obvious reasons (there is no top, hi). > > 73,ron, n9ee/r > > >From: Jim Cicirello <[EMAIL PROTECTED] <mailto:ka2ajh%40gmail.com> com> > >Date: 2008/06/24 Tue AM 11:11:02 EDT > >To: Repeater-Builder@ <mailto:Repeater-Builder%40yahoogroups.com> yahoogroups.com > >Subject: Re: [Repeater-Builder] Reasonably low wind load antenna > > > > >Hi Ron Another Question Please: I was fortunate enough to buy a good DB224 without the support mast. After following the opinions on wind loading, etc. I am wondering what can be used for a support mast and where the masting might be purchased? Any ideas? Thanks JIM KA2AJH ----- Original Message ----- From: Ron Wright To: Repeater- Builder@ <mailto:Repeater-Builder%40yahoogroups.com> yahoogroups.com Sent: Tuesday, June 24, 2008 7:47 AM Subject: Re: [Repeater-Builder] Reasonably low wind load antenna > > > >Tony, > > > >First the Ringo-Ranger does not have the 7 dbi gain. To think a smaller 12 ft antenna would have about the same gain as one the size of a 4 bay dipole is not realistic. One note of info...antenna manufactures, especially from Japan, lie all the time. I would not use such harsh words except after years of this junk something needs to be said. I is said here on this board all the time for many know antenna performance here, hi. > > > >Your wind loading limits will require a smaller, lower gain antenna. If ice is a problem the Ringo-Ranger will probably not last that long. > > > >I would recommend going to www.tessco.com, a distributor of 2-way gear, and check thru their antenna section. They have a number of finnne manufactures with their specs. > > > >73, ron, n9ee/r > > > >>From: Tony VE6MVP <[EMAIL PROTECTED] <mailto:tony%40ve6mvp.com> com> > >>Date: 2008/06/23 Mon PM 10:28:11 EDT > >>To: Repeater-Builder@ <mailto:Repeater-Builder%40yahoogroups.com> yahoogroups.com > >>Subject: [Repeater-Builder] Reasonably low wind load antenna > > > >> > >>Folks > >> > >>We're moving a VHF amateur repeater to a 96' Trylon self supportingtower. The overwhelming opinion is that our current 210C4 four bayfolded dipole would be too much of a weight and wind load for thattower. > >> > >>One comment has been the Ringo Ranger. The wind load of theCushcraft Ringo Ranger II ARX2Bhttp://cushcraft.com/comm/support/pdf/RINGOS%20AR2%206%2010% 20ARX450%20220B%202B.pdfis 0.5 square feet. The windload of the Sinclar SD214 http://www.sinclair <http://www.sinclairtechnologies.com/catalog/resources/pdf/SD214- HF2P3LDF> technologies.com/catalog/resources/pdf/SD214-HF2P3LDF(D00S- LSABK)-DI.pdf (newer model to 210C4) is 5.57 square feet. Although the ice area is 17.04 sq ft. The SD214 has a dbd gain of 7.2, dbi of 9.3. The Ringo Ranger has dbi gain of 7.0. However the coverage plot in rural slightly hilly Alberta isn't all that much different. > >> > >>What would be suggestions for an alternative? Comments? > >> > >>Thanks, Tony > >>(rapidly learning lots about towers and repeaters) > > > >Ron Wright, N9EE > >727-376-6575 > >MICRO COMPUTER CONCEPTS > >Owner 146.64 repeater Tampa Bay, FL > >No tone, all are welcome. > > > > > > Ron Wright, N9EE > 727-376-6575 > MICRO COMPUTER CONCEPTS > Owner 146.64 repeater Tampa Bay, FL > No tone, all are welcome. >
