RE: [Repeater-Builder] LMR-400 Cable

2008-10-05 Thread no6b
At 10/3/2008 00:10, you wrote: Here is the latest. I terminated the cable at the antenna with a dummy load and no desense. I hooked back up to the antenna and if listen to the receiver with the squelch open I hear a buzz in the background of the receiver white noise audio in addition to desense

RE: [Repeater-Builder] LMR-400 Cable

2008-10-04 Thread Tom Elmore
To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] LMR-400 Cable At 10/2/2008 05:41, you wrote: Hello Tom, I think that the clue here is that you had desense with both the RG-213 and the LMR-400. My guess would be that there is some mismatch between the antenna

Re: [Repeater-Builder] LMR-400 Cable

2008-10-04 Thread Scott Overstreet
To: Repeater-Builder@yahoogroups.com Sent: Friday, October 03, 2008 12:10 AM Subject: RE: [Repeater-Builder] LMR-400 Cable Here is the latest. I terminated the cable at the antenna with a dummy load and no desense. I hooked back up to the antenna and if listen to the receiver

RE: [Repeater-Builder] LMR-400 Cable

2008-10-03 Thread no6b
At 10/2/2008 16:06, you wrote: Hi Tom, As others have said, try the dummy load at the antenna end of the cable and see if there is any desense. Then try disconnecting the antenna input to the receiver from the duplexer and place a dummy load on the receiver. Turn on the transmitter and

Re: [Repeater-Builder] LMR-400 Cable

2008-10-02 Thread kd6aaj
I suspect you my need hardline for that distance.   I have an interesting theory...   What if the length of coax actually were actually long enough for the tx signal to remain on the wire while in RX mode? Probably need to be a mile long ;)   Another thought; anyone ever run seperate long cables

RE: [Repeater-Builder] LMR-400 Cable

2008-10-02 Thread ka9qjg
Tom, I don't think it is Your Coax , I use 75 Ft of LMR-400 on a 220 Repeater 130 Watt Amp G-7 I have this set up at the site and at home for testing and Never have had a problem , I do intend to up grade to a Better low loss Coax , But at 6 Meter 60 Ft would be fine I think You will get

Re: [Repeater-Builder] LMR-400 Cable

2008-10-02 Thread Milt
The next step in your troubleshooting would be to move that dummy load to the other end of the coax and repeat the desense test; that checks your coax and duplexer. If everything checks OK then move on to substituting a different antenna. I would suggest that you construct a basic ground

Re: [Repeater-Builder] LMR-400 Cable

2008-10-02 Thread Chuck Kelsey
There has been example after example of people replacing foil/braid cable with heliax and the end result was elimination of the problem that you are experiencing. Yes, there are isolated examples of people getting away with using the foil/braid coax, but they are far and few between. You

Re: [Repeater-Builder] LMR-400 Cable

2008-10-02 Thread Joe
Hello Tom, I think that the clue here is that you had desense with both the RG-213 and the LMR-400. My guess would be that there is some mismatch between the antenna and the duplexer. The duplexer may be tuned for a 50 resistive ohm load, but the antenna system is presenting some other

Re: [Repeater-Builder] LMR-400 Cable

2008-10-02 Thread no6b
At 10/1/2008 10:06, you wrote: I recently put a six meter repeater (52.810/51.110) on the air here in Anchorage, Alaska. I am feeding it with about 60 feet of LMR-400 cable and am experiencing quite a bit of desense. I did a search for LMR-400 in duplex operation and came across several posts

RE: [Repeater-Builder] LMR-400 Cable

2008-10-02 Thread Gary Schafer
Hi Tom, As others have said, try the dummy load at the antenna end of the cable and see if there is any desense. Then try disconnecting the antenna input to the receiver from the duplexer and place a dummy load on the receiver. Turn on the transmitter and see if you still have desense. If

Re: [Repeater-Builder] LMR-400 Cable

2008-10-02 Thread Chuck Kelsey
: Thursday, October 02, 2008 7:14 PM Subject: Re: [Repeater-Builder] LMR-400 Cable Tom, With 65 feet of cable, your feed line is very close to a resonant length at 6 m. Actually about 3 wavelengths. If you have enough extra coax length, try winding some of it into a coil and see

Re: [Repeater-Builder] LMR-400 Cable

2008-10-02 Thread Milt
Subject: Re: [Repeater-Builder] LMR-400 Cable I suspect that he has notch cavity resonators. Each can is about two feet tall, more or less. So, while eight of them take up some space, they are not likely as large as you envision. Chuck WB2EDV - Original Message - From: [EMAIL

RE: [Repeater-Builder] LMR-400 Cable

2008-10-02 Thread Eric Lemmon
To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] LMR-400 Cable I suspect that he has notch cavity resonators. Each can is about two feet tall, more or less. So, while eight of them take up some space, they are not likely as large as you envision. Chuck WB2EDV - Original

Re: [Repeater-Builder] LMR-400 Cable

2008-10-02 Thread no6b
At 10/2/2008 05:41, you wrote: Hello Tom, I think that the clue here is that you had desense with both the RG-213 and the LMR-400. My guess would be that there is some mismatch between the antenna and the duplexer. The duplexer may be tuned for a 50 resistive ohm load, but the antenna system is