It came with some cutting charts to cut the 3 inside elements inside of a plastic tube. I cut those and checked the SWR with 10 ft piece of RG-58 25 watts input and it read 1.5-1. Assumed everything was okay. Cable was put on a dummy load and cable tested great with no shortages and very low loss. 3-4 watts from 40 watt input. After testing several times the more power that was put into the feedline the higher the SWR was. The lower power I put in the lower the SWR was. My tower that it is on is not grounded and the antenna calls for DC ground for lightning protection so I might need to ground the antenna. Anyone think that will help SWR any?
--- In [email protected], Wayne Leake <wa2...@...> wrote: > > I can't say for certain, but have you checked the antenna prior to > putting it on the tower? > I have a high gain antenna ion a twoer, need to get the heliax > connected to it, but i tested in on a post before I put it on the > twoer > > Also, LMR400 is not recommended for full duplex use. that type of > cable can cause noise problems under full duplex conditions. > I sometimes test cables as well, connecting them to a good dummy > load, and test several ways. > I have an analyzer, actually 2 of the, one only for the 70 centimeter > band, and also check with a Bird 43 watt meter looking at reflected as > well as forward power. > > matter of fact, I have some coax assembled by Cable Expertys taht > turns out some has fare more loss than another, both 100 feet About 65 > watts from a GE Mastr II repeater on the 440 band shows about 4 watts > at the other end, and one less than 1 watt. Something not right there. > So it is possible the coax and/or connectors have a problem > By mounting my antenna low and using a known good jumper from my 440 > analyzer. I determined the SWR was very low on the antenna. And > testing cables will show you where the problem might be. > Also, where are you inserting the meter? That can make a difference > I tested my loss in my duplexer by testing watts before it and watts > out. Found good for the rated insertion loss. > And little reflected power on the transmitter side of the duplexer. > the word is, test, test and test. > test each part of the antenna system to locate where the problem really is... > > Wayne WA2YNE > > > On Sat, May 23, 2009 at 8:17 PM, agrimm0034 <agrimm0...@...> wrote: > > > > > > Currently just upgraded my home built GMRS Maxtrac repeater to a new 6.5db > > Gain Tran-Max antenna. Says SWR should be 1.5 - 1 or less and I have a > > reading of 2.5 - 1. I'm using LMR 400 ultra low loss cable at 40 ft putting > > in 40 watts of power. The antenna is mounted on 40 ft tower old 3 legged > > style. Nothing is around the antenna and check cable to make sure it wasn't > > shorted and everything seems to be fine. Any ideas on how to make the > > Standing Wave better? > > > > >
