Have a G7-144 on our ARMY MARS repeater here and has been up since 1998 with no antenna issues. We removed the clamps and drilled holes after tuning the antenna to our frequency and used sheet metal screws to secure the tubing. The antenna is mounted on the top of a building about 180 ft.
David -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Eric Lemmon Sent: Sunday, October 11, 2009 11:45 AM To: [email protected] Subject: RE: [Repeater-Builder] Antenna question John, My suggestion is simple: Find the money to buy a decent antenna. Unless your time has no value, your gasoline is free, and you enjoy tower climbing, don't mess with cheap antennas. The great majority of available funds should go into the antenna, feedline, and outdoor mounting hardware- the things that are costly to buy, difficult to install, and the most likely to break during bad weather when it may be dangerous or impossible to get to the site to make repairs. Are you planning to support the Heliax with standoff cushion clamps made of stainless steel, or were you planning to just tie-wrap it to the tower legs? At $20 or so each, just the Heliax supports become a high-cost item when you install one every 3 or 4 feet. The indoor stuff like the repeater and duplexer can be upgraded over time, in the relative comfort and safety of the equipment shelter. Moreover, IMHO, it is not prudent to spend big bucks on the radio and duplexer up front, and then skimp on stuff that goes on the tower. The Hustler G7-144 is really too flimsy to have in repeater service where it is exposed to high winds and temperature extremes. I assembled a G7-144 antenna for my radio club's base station, and I took pains to use Penetrox on all aluminum joints and silicone sealant or Scotch-Kote on dissimilar-material joints. Despite these precautions, water leaked into the base and caused severe corrosion. It's practically junk now. If your repeater site is at one side of the desired coverage area, you might look into offset-pattern dipole antennas, Yagis, or corner reflectors. It makes no sense to put an omni antenna in service where all of the potential users are in one sector. 73, Eric Lemmon WB6FLY -----Original Message----- From: Repeater-Builder@ <mailto:Repeater-Builder%40yahoogroups.com> yahoogroups.com [mailto:Repeater-Builder@ <mailto:Repeater-Builder%40yahoogroups.com> yahoogroups.com] On Behalf Of W3ML Sent: Sunday, October 11, 2009 7:09 AM To: Repeater-Builder@ <mailto:Repeater-Builder%40yahoogroups.com> yahoogroups.com Subject: [Repeater-Builder] Antenna question Hi again, We are looking to replace that used antenna after getting 100 feet of new Andrew 1/2" donated to our club. Now I realize that the DB type antenna is the best, but we do not have 800 bucks to buy one. So, my question is should we just get a new G7-144 to replace the used G7 or is there another type of vertical that we could get that would be good. Being in North Indiana, our winters can be quite brutal, so we would probably want something durable. Any suggestions. 73 John, W3ML
