Re: [Repeater-Builder] Anetenna Help
Jeff DePolo wrote: Somebody, maybe Larsen or Antenna Specialists, used to make a stiffener for use with NMO mounts. It was basically an oversized brass fender washer with a 3/4 hole in the center. It was thick enough that it stiffened the body near the mount, but flexible enough that it would take the shape of the concave contour of the roof when you tightened down the NMO. I haven't seen them advertised in a while, not sure if they're still made. I had a Diamond dual-bander act as a can-opener to the roof of one of my previous trucks (Chevy Tahoe). It got snagged on a low-hanging ice-laden branch on the way up to a tower site. The roof gave up before the antenna did. I guess that says something about Diamond mobile antennas...? --- Jeff I didn't quite get to the can opener stage with one, but I had a Diamond survive a tree event on top of a Ford pickup truck years ago also... The mount in the roof left a large concave dent around it, with cracking around the hole. I removed the smaller mount, drilled it out for an NMO, and put a smaller antenna in that hole... ... and found a better place to mount the Diamond on a bracket. The Diamond did need a few minutes of tightening of the various allen screws after that one, but no damage to the antenna. I've gone through two of the large Diamond dual-banders (umm... what is that model number, the SG9000? 7/8 wave on 2m and three co-linear 1/4 waves on 70cm)... and utterly destroyed a TechAmerica clone of the same antenna. The big Diamond's last many years, the clone died in two. I'm mean as hell to antennas, and I want big ones that work well, and I always mount them up high, so I'm always hitting them on things. On the Jeep Cherokee the Diamond antennas mixed with Comet or Diamond articulated mounts on the liftgate seem to work best. One monster VHF/UHF on one side, and the ATAS-100 on the other. My dad's recent visit to HRO got a score for me... he knew I liked and used those antennas and someone had put one in on consignment that had never been opened... instant 30% discount! (Yay!) It's now in the garage awaiting the death of the current one, which may not be too far away... starting to see some plastic cracking in the smaller coil form, and there's a tiny chunk missing. Must'a hit something with it again. :-) Nate WY0X Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Anetenna Help
Just about any 5/8 wave antenna mounted on top of a Ford pickup truck. The roof metal is so thin that frequent flexing from antenna sway, wind resistance, low tree branch contact can cause metal fatigue on thecab roof. The antenna NMO mount was installeddirectly above the cab interior light. Nice install but the metal finally cracked about 1/2 inchcircumference further outfrom the outer edge of the NMO mount. The singing problem was resolved by wrapping thin fishing line around the full antenna length at about 1 turn per 1 1/2 inches for its full length. The thinner the whip antenna the higher the audio frequency.Observe automobile antennas and you will see many factory manufactured AM/FM antennas wrapped as mentioned above. Go out and wiggle your mobile antenna. Look at the automobile metal near the base. Watch it flex. The longer the antenna the more flexing. I solved the problem by relocating the antenna using a homemade bracket mounted between the front fender and hoodnearcorner of windshield. Gary K2UQ YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
RE: [Repeater-Builder] Anetenna Help
Somebody, maybe Larsen or Antenna Specialists, used to make a "stiffener" for use with NMO mounts. It was basically an oversized brass fender washer with a 3/4" hole in the center. It was thick enough that it stiffened the body near the mount, but flexible enough that it would take the shape of the concave contour of the roof when you tightened down the NMO. I haven't seen them advertised in a while, not sure if they're still made. I had a Diamond dual-bander act as a can-opener to the roof of one of my previous trucks (Chevy Tahoe). It got snagged on a low-hanging ice-laden branch on the way up to a tower site. The roof gave up before the antenna did. I guess that says something about Diamond mobile antennas...? --- Jeff From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED]Sent: Thursday, April 20, 2006 3:46 PMTo: Repeater-Builder@yahoogroups.comSubject: Re: [Repeater-Builder] Anetenna Help Just about any 5/8 wave antenna mounted on top of a Ford pickup truck. The roof metal is so thin that frequent flexing from antenna sway, wind resistance, low tree branch contact can cause metal fatigue on thecab roof. The antenna NMO mount was installeddirectly above the cab interior light. Nice install but the metal finally cracked about 1/2 inchcircumference further outfrom the outer edge of the NMO mount. The singing problem was resolved by wrapping thin fishing line around the full antenna length at about 1 turn per 1 1/2 inches for its full length. The thinner the whip antenna the higher the audio frequency.Observe automobile antennas and you will see many factory manufactured AM/FM antennas wrapped as mentioned above. Go out and wiggle your mobile antenna. Look at the automobile metal near the base. Watch it flex. The longer the antenna the more flexing. I solved the problem by relocating the antenna using a homemade bracket mounted between the front fender and hoodnearcorner of windshield. Gary K2UQ YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] Anetenna Help
Not sure of thepost that started this, but I needed a good antenna mount for my pickup and got tired of drilling holes, etc. into the top of the cab and knew that lip mount antennas on the hood do not work because of reflections from the car. I also do not like mag mounts. I took the suggestion of a local ham and put a "headache rack" on the truck. I did not know what that was, but to the uninitiated, it is mounted behind the cab to protect the window from objects coming from the bed thru the rear window when you load stuff back there. It also is useful for tying down long loads (like crappie pole antennas!) to it. But the best use for it is the mounting of two or more antennas to it made easy by the vertical posts most racks have on either side of the bed just behind the cab. Mine hassquare vertical tubes, whereat their top most point, I made a simple aluminum angle piece to mount a 2 meter and a 220 MHz NMO antenna mounts. They are up and above the cab having good radiation views.The antennas dostick upabove the cab the height of the antenna, but they work great. Irouted the cables into the cab at the back lower edge of the doors (thru some rubber grommeted holes in the front of the bed), since I do not have a bunch of traffic in and out of them, it is no problem.The truck is a F-250. Roger W5RD - Original Message - From: Jeff DePolo To: Repeater-Builder@yahoogroups.com Sent: Thursday, April 20, 2006 3:20 PM Subject: RE: [Repeater-Builder] Anetenna Help Somebody, maybe Larsen or Antenna Specialists, used to make a "stiffener" for use with NMO mounts. It was basically an oversized brass fender washer with a 3/4" hole in the center. It was thick enough that it stiffened the body near the mount, but flexible enough that it would take the shape of the concave contour of the roof when you tightened down the NMO. I haven't seen them advertised in a while, not sure if they're still made. I had a Diamond dual-bander act as a can-opener to the roof of one of my previous trucks (Chevy Tahoe). It got snagged on a low-hanging ice-laden branch on the way up to a tower site. The roof gave up before the antenna did. I guess that says something about Diamond mobile antennas...? --- Jeff From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED]Sent: Thursday, April 20, 2006 3:46 PMTo: Repeater-Builder@yahoogroups.comSubject: Re: [Repeater-Builder] Anetenna Help Just about any 5/8 wave antenna mounted on top of a Ford pickup truck. The roof metal is so thin that frequent flexing from antenna sway, wind resistance, low tree branch contact can cause metal fatigue on thecab roof. The antenna NMO mount was installeddirectly above the cab interior light. Nice install but the metal finally cracked about 1/2 inchcircumference further outfrom the outer edge of the NMO mount. The singing problem was resolved by wrapping thin fishing line around the full antenna length at about 1 turn per 1 1/2 inches for its full length. The thinner the whip antenna the higher the audio frequency.Observe automobile antennas and you will see many factory manufactured AM/FM antennas wrapped as mentioned above. Go out and wiggle your mobile antenna. Look at the automobile metal near the base. Watch it flex. The longer the antenna the more flexing. I solved the problem by relocating the antenna using a homemade bracket mounted between the front fender and hoodnearcorner of windshield. Gary K2UQ YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] Anetenna Help
At 4/20/2006 12:46 PM, you wrote: Just about any 5/8 wave antenna mounted on top of a Ford pickup truck. The roof metal is so thin that frequent flexing from antenna sway, wind resistance, low tree branch contact can cause metal fatigue on the cab roof. The antenna NMO mount was installed directly above the cab interior light. Nice install but the metal finally cracked about 1/2 inch circumference further out from the outer edge of the NMO mount. The singing problem was resolved by wrapping thin fishing line around the full antenna length at about 1 turn per 1 1/2 inches for its full length. The thinner the whip antenna the higher the audio frequency. Observe automobile antennas and you will see many factory manufactured AM/FM antennas wrapped as mentioned above. Go out and wiggle your mobile antenna. Look at the automobile metal near the base. Watch it flex. The longer the antenna the more flexing. I solved the problem by relocating the antenna using a homemade bracket mounted between the front fender and hood near corner of windshield. Gary K2UQ Your mounting arrangement may be mechanically superior, but it's electrically inferior. Aside from the distorted antenna pattern you'll get, you'll also get a lot more RF into the cab. I noticed when riding with a friend who mounted his antenna in the same place you did that I could not duplex using my HT as the receiver because the RF from his mobile radio completely wiped out my HT's receiver even when transmitting on low power on the mobile. I don't have this problem at all in my car, which has the mobile antenna mounted in the middle of the roof. This is because the roof acts as a shield: no RF can get inside the passenger compartment until it loops around the edges of the roof, by then most of the current has radiated away (at least at UHF). I'll take my chances with the roof keep the RF out of my face, thank you. Bob NO6B Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Anetenna Help
To: KB1CHU..Don't sell that little thru the glass dual bander antenna from Radio Shack short. I have one mounted on the tinted glass side window of my suburban and it is a dandy little antenna. I tuned mine for a 2 meter frequency, have no desire to use it on 440 mhzandthe R/S antserves me quite well. If for some reason it disappeared, I would replace it with another exact model. For those who like to bang tree limbs, bend the thin metal of their automobiles and listen to the singing breezes while driving, that's great but for a little powerhouse that does a darn nice job, that thru the glass R/S antenna is right up there with the big boys. Gary K2UQ Trenton, NJ YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] Anetenna Help
[EMAIL PROTECTED] wrote: For those who like to bang tree limbs, bend the thin metal of their automobiles and listen to the singing breezes while driving, that's great but for a little powerhouse that does a darn nice job, that thru the glass R/S antenna is right up there with the big boys. Heh-what kind of antennas are you putting on your cars that do any of that??? Yikes! -- Jim Barbour WD8CHL Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Anetenna Help
I have a dual band antenna from Radio Shacknew in the package but old stock ( I bought a lot of stuff from a radio shack that was overstock). It comes with a length of cable,mount and antenna. The catch is it is a through the glass mount. Be aware that they don't work well with certain tinted windows. If youneed it send me your mailing address and it will go out this week. If not I'll find a use for it at some point. I also have a single band 2 meter 5/8 wave mag mount antenna with cable. It would not be good for 70cm as it would not match up. Let me know which one you want if you can use one of them. KB1CHU YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] Anetenna Help
Thomas Flint wrote: I have a dual band magent mount antenna, the other day during high winds I lost the antenna part. Do to financial issues I am unable to buy another at this time. Does anyone know of away I can make it work using something else in its place. Any help would be greatly appreciated. KL0LS A 1/4-wave cut for abt 147 will sorta work on UHF as a 3/4-wave. Pattern's not the greatest, but usable...ymmv... -- Jim Barbour WD8CHL Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Anetenna Help
I've made an antenna whip out of a stainless steel heliac welding rod. If you can scounge one, that might work. Paul, kb9wlc --- Thomas Flint [EMAIL PROTECTED] wrote: I have a dual band magent mount antenna, the other day during high winds I lost the antenna part. Do to financial issues I am unable to buy another at this time. Does anyone know of away I can make it work using something else in its place. Any help would be greatly appreciated. KL0LS Yahoo! Groups Links [EMAIL PROTECTED] __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Anetenna Help
Hi you don't say what bands. I assume 144 and 430 why not as a temp measure just use a 1/4 wave rod and change it for whatever band you want to use. 144 is around 20 inches 430 around 6 73 Steve - Original Message - From: Thomas Flint [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, April 07, 2006 12:50 AM Subject: [Repeater-Builder] Anetenna Help I have a dual band magent mount antenna, the other day during high winds I lost the antenna part. Do to financial issues I am unable to buy another at this time. Does anyone know of away I can make it work using something else in its place. Any help would be greatly appreciated. KL0LS Yahoo! Groups Links -- Internal Virus Database is out-of-date. Checked by AVG Free Edition. Version: 7.1.385 / Virus Database: 268.3.0/290 - Release Date: 23/03/06 Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Anetenna Help
--- Thomas Flint [EMAIL PROTECTED] wrote: I have a dual band magent mount antenna, the other day during high winds I lost the antenna part. Do to financial issues I am unable to buy another at this time. Does anyone know of away I can make it work using something else in its place. Any help would be greatly appreciated. KL0LS YOu may be able to stick a 19 to 20 inch wire, stainless steel welding rod or similar in the mount. If it is just a mount and does not have a matching network in it , it will work both bands. Should work fine on 2 meters and while the radiation patern may not be that great for the 440 band, it will load and work the local stuff. __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
