Re: [Repeater-Builder] DB Products VHF UHF on same mast?
I operate an antenna with a full size DB-224 and an 8 dipole 440 antenna on the same mast and found that the 2 meter transmitter does not bother the 440 receiver, but I do get some desense with the 440 transmitter into the 2 meter radio. An extra bandpass cavity on the 2 meter receiver cleared that up. GE Mastr II on both bands. I think that the 2 meter dipoles can absorb more power from the 440 antennas than the other way around, since the third harmonic is resonant on the 2 meter dipoles. I have also operated a DB-224 on 440 with some success. I tried a diplexer to combine the two antennas to one feedline without much success. I wound up using a separate feedline for each antenna and it worked much better. 73 - Jim W5ZIT --- On Mon, 7/20/09, tahrens301 tahr...@swtexas.net wrote: From: tahrens301 tahr...@swtexas.net Subject: [Repeater-Builder] DB Products VHF UHF on same mast? To: Repeater-Builder@yahoogroups.com Date: Monday, July 20, 2009, 10:11 PM I've got a DB-224 that is going up the tower in a while when I get the hardline, but control issues have changed from land line to 440mhz control. So I need 2 antennas. Today I saw a hybrid DB antenna, effectively a 224, plus a 16 element DB, all on the same mast. Is this something that can be done without having each antenna interact with the other? Sounds like a good idea to me. Just curious, Thanks, Tim W5FN
RE: [Repeater-Builder] DB Products VHF UHF on same mast?
If you have a VHF 224 just take a DB411 UHF and mount on the opposite side of the mast 180deg from the VHF loops. We do it all the time out here and works great. Just run two coax cables and all is nice and neat. Best of both worlds, you get two antennas on the same mast without using another 10 or so feet of tower space. There is only one catch, you may want to top support the DB224 antenna since you are adding additional loops. Mike Mike Mullarkey K7PFJ 6886 Sage Ave Firestone, Co 80504 303-954-9695 Home 303-954-9693 Home Office Fax 303-718-8052 Cellular From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of tahrens301 Sent: Monday, July 20, 2009 9:11 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] DB Products VHF UHF on same mast? I've got a DB-224 that is going up the tower in a while when I get the hardline, but control issues have changed from land line to 440mhz control. So I need 2 antennas. Today I saw a hybrid DB antenna, effectively a 224, plus a 16 element DB, all on the same mast. Is this something that can be done without having each antenna interact with the other? Sounds like a good idea to me. Just curious, Thanks, Tim W5FN No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.392 / Virus Database: 270.13.20/2251 - Release Date: 07/20/09 18:29:00
Re: [Repeater-Builder] DB Products VHF UHF on same mast?
Is your control a receive only, or is it a UHF control repeater? I've seen a 2m antenna used to feed both a 2m receiver and a UHF receiver. After all, the third harmonic of 147 MHz is 441 mhz. At 08:11 PM 07/20/09, you wrote: I've got a DB-224 that is going up the tower in a while when I get the hardline, but control issues have changed from land line to 440mhz control. So I need 2 antennas. Today I saw a hybrid DB antenna, effectively a 224, plus a 16 element DB, all on the same mast. Is this something that can be done without having each antenna interact with the other? Sounds like a good idea to me. Just curious, Thanks, Tim W5FN Yahoo! Groups Links
[Repeater-Builder] DB Products VHF UHF on same mast?
I've got a DB-224 that is going up the tower in a while when I get the hardline, but control issues have changed from land line to 440mhz control. So I need 2 antennas. Today I saw a hybrid DB antenna, effectively a 224, plus a 16 element DB, all on the same mast. Is this something that can be done without having each antenna interact with the other? Sounds like a good idea to me. Just curious, Thanks, Tim W5FN
Re: [Repeater-Builder] DB Products VHF UHF on same mast?
If you dont need maximim range on the uhf side I just put a vhf/uhf duplexer at the transmitters and use the vhf antenna for uhf. Not very effecient but it does work. Basically the uhf band is the third harmonic of the vhf band. I use a 1/4 wave 2 meter antenna on my wifes car with her ic207h dualband radio and it works good on both bands with low reflected power. - Original Message - From: tahrens301 To: Repeater-Builder@yahoogroups.com Sent: Monday, July 20, 2009 10:11 PM Subject: [Repeater-Builder] DB Products VHF UHF on same mast? I've got a DB-224 that is going up the tower in a while when I get the hardline, but control issues have changed from land line to 440mhz control. So I need 2 antennas. Today I saw a hybrid DB antenna, effectively a 224, plus a 16 element DB, all on the same mast. Is this something that can be done without having each antenna interact with the other? Sounds like a good idea to me. Just curious, Thanks, Tim W5FN
