Posted: 4/18/2010 7:44:27 PM EDT
|
Has anyone modified a small mag base antenna for use on a backpack? I was ocnsidering sacrificing one, and weaving it through the molle webbing of a backpack on the outside.
I looked around and looks like there are plenty of military antennas for personal area networks but didn't see any commercial units in the HAM band. Just looking for something better then the stubby yaggi on the handheld. Making my own 2 meter and just soldering on the conencto is another possibility... |
|
I don't normally steer people away from ARFCOM for answers, but in this case:
http://hfpack.com/ |
|
A little expensive, but people love them around the world.
http://www.buddipole.com/ |
|
That looks awesome but not quite what I'm looking to do. I don't want to hike a massive antenna to the mountain top (although aparently a bunch of people near tapanzee bridge in ny did that today and made contact with us). I want to be able to hit the local repeater/other hikers as I hike. I figure an antenna upgrade is worth the 1 unused magbase antenna and 1 vertical unused row of MOLLE. |
|
Quoted:
I don't normally steer people away from ARFCOM for answers, but in this case: http://hfpack.com/ Cool thank you. Going through the site. Looks like most of it is radio-dedicated pack builds but I'll probably find something low key/low weight in there. |
|
Quoted:
Has anyone modified a small mag base antenna for use on a backpack? I was ocnsidering sacrificing one, and weaving it through the molle webbing of a backpack on the outside. I looked around and looks like there are plenty of military antennas for personal area networks but didn't see any commercial units in the HAM band. Just looking for something better then the stubby yaggi on the handheld. Making my own 2 meter and just soldering on the conencto is another possibility... A mag mount antenna depends on the car body for being the ground plane... and using the antenna only, no ground plane. BUT, there is a better solution for 2m... the "roll up J-pole" or "slim jim". Remember, for 2m, power is not the problem... antenna height is everything. So, anything you can do to jack it up is good... hoisting up over a tree limb, whatever. Here's one already made up. You can't buy the materials for the price, and it is tuned and works. Order with your choice of connector, with or without coax, and 2m only, or 2m/70cm dual band versions. http://www.2wayelectronix.com/ http://www.hamuniverse.com/n9taxslimjimreview.html Review I have one of these, the 2m only, without coax, in my kit. |
|
Quoted:
Quoted:
Has anyone modified a small mag base antenna for use on a backpack? I was ocnsidering sacrificing one, and weaving it through the molle webbing of a backpack on the outside. I looked around and looks like there are plenty of military antennas for personal area networks but didn't see any commercial units in the HAM band. Just looking for something better then the stubby yaggi on the handheld. Making my own 2 meter and just soldering on the conencto is another possibility... A mag mount antenna depends on the car body for being the ground plane... and using the antenna only, no ground plane. BUT, there is a better solution for 2m... the "roll up J-pole" or "slim jim". Remember, for 2m, power is not the problem... antenna height is everything. So, anything you can do to jack it up is good... hoisting up over a tree limb, whatever. Here's one already made up. You can't buy the materials for the price, and it is tuned and works. Order with your choice of connector, with or without coax, and 2m only, or 2m/70cm dual band versions. http://www.2wayelectronix.com/ http://www.hamuniverse.com/n9taxslimjimreview.html Review I have one of these, the 2m only, without coax, in my kit. Those look like they're for a stationary setup, not for on the use while hiking (as in actually moving, not stopping). I'm looking more for a civilian version of this in VHF/UHF band http://cgi.ebay.com/MBITR-Tactical-Vest-Antenna-System_W0QQitemZ190363592709QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item2c528de805 |
|
External frame pack + mirror antenna mount. Then just make sure the mount has the right threads for whatever antenna you wanna put on it. note: your counterpoise (frame) is gonna be less than the antenna was designed for (a car) if you pick a mobile antenna so you might have an issue with that. A 'high gain' HT antenna on a BNC/SMA mount might work a bit better.
Easiest, make a 2M 1/4 wave ground plane out of an SO-239 mount like 
mount it in some 1/2 inch PVC and lash it to the frame. Hell, done right you could cophase some dipoles 2M dipoles off your pack and give you a little directionality. 
|
|
Quoted:
External frame pack + mirror antenna mount. Then just make sure the mount has the right threads for whatever antenna you wanna put on it. note: your counterpoise (frame) is gonna be less than the antenna was designed for (a car) if you pick a mobile antenna so you might have an issue with that. A 'high gain' HT antenna on a BNC/SMA mount might work a bit better. Easiest, make a 2M 1/4 wave ground plane out of an SO-239 mount like http://www.hamuniverse.com/2mgrnplane.jpg mount it in some 1/2 inch PVC and lash it to the frame. Hell, done right you could cophase some dipoles 2M dipoles off your pack and give you a little directionality. Thank you, looks like project time. I was hoping to go with something small, but better then rubber duckie antenna |
|
I bought an MFJ extended dual band antenna (with a BNC on the end) that is about 15 inches long. It is good for about 1 or two S units on my Icom V82. That is almost not worth the effort, but it is for back country use and a little might get you out. Hustler make an SF-2 that is a 5/8 two meter mobile antenna with a 3/8-24 thread on the bottom. These are about 60 inches long and are for 146 MHz. If you can rig a ground plane to your pack, it might work for you. I bought two of these with one to use with a ground plane on my portable two meter repeater. I plan to put the other on my Bronco to use with an Icom 2100 mobile. I have not done any testing on these yet.
RS |
|
Just get an SMA-24 (http://www.cometantenna.com/products.php?CatID=1&famID=1&childID=4) or the Opek brand of the exact same antenna HR-603VU-SMA, which I have (http://www.opektech.com/RubberDuckAntennas.html) and then one of the SMA remote clip mounts:
http://www.opektech.com/Small_Clip_Mounts.html Try the clip-on mount attached to the top of your pack. Obviously you'll have to duck a lot in the woods. BTW, that Opek 15-inch is my favorite HT antenna. The best I've tried short of my monstrous 1/2 wave telescopic connector-destroyer. |
|
Quoted:
Quoted:
External frame pack + mirror antenna mount. Then just make sure the mount has the right threads for whatever antenna you wanna put on it. note: your counterpoise (frame) is gonna be less than the antenna was designed for (a car) if you pick a mobile antenna so you might have an issue with that. A 'high gain' HT antenna on a BNC/SMA mount might work a bit better. Easiest, make a 2M 1/4 wave ground plane out of an SO-239 mount like http://www.hamuniverse.com/2mgrnplane.jpg mount it in some 1/2 inch PVC and lash it to the frame. Hell, done right you could cophase some dipoles 2M dipoles off your pack and give you a little directionality. Thank you, looks like project time. I was hoping to go with something small, but better then rubber duckie antenna Anything physically smaller than that antenna is a compromise. Now, you could take A-Free-Man's idea for the roll up J pole, and mount it inside the 1/2" PVC. This would give you performance/gain, flexability in mounting, and ruggedness. |
|
Roll up J-Pole, attached to an inexpensive fiberglass fishing pole iwih the guides removed and cut to teh right length. Works like a champ, and the inexpesive crappie poles are flexible enough to bend back on branches.
Cabellas has the cheap crappie poles udner $10. ETA- thinking about this more, use a cheap fly rod, it is lighetr and more flexible. Buy one of those fly fishing starter kits and you get a reel as well, and the fly reels are great ways to wind up portable long wire antennas 
|
|
Quoted:
Quoted:
What frequencies do you want to use the antenna for? VHF/UHF, we were using 146.525 today That's a really bad choice in frequency by the way. Why would you pick 5khz off of the national simplex frequency? Or do they not cover the concept of bandwidth on tests anymore? |
|
Quoted:
Quoted:
Quoted:
What frequencies do you want to use the antenna for? VHF/UHF, we were using 146.525 today That's a really bad choice in frequency by the way. Why would you pick 5khz off of the national simplex frequency? Or do they not cover the concept of bandwidth on tests anymore? I saw there was activity on the frequency in the area(scanners are addicting). Something about 'radios on the mountaintops' and we were hiking up to the mountaintop, so an opportunity to say hi to people on adjacent mountaintops int he same state park. |
|
Quoted:
Roll up J-Pole, attached to an inexpensive fiberglass fishing pole iwih the guides removed and cut to teh right length. Works like a champ, and the inexpesive crappie poles are flexible enough to bend back on branches. Cabellas has the cheap crappie poles udner $10. ETA- thinking about this more, use a cheap fly rod, it is lighetr and more flexible. Buy one of those fly fishing starter kits and you get a reel as well, and the fly reels are great ways to wind up portable long wire antennas Thank you, investigating that option |
|
Quoted:
Just get an SMA-24 (http://www.cometantenna.com/products.php?CatID=1&famID=1&childID=4) or the Opek brand of the exact same antenna HR-603VU-SMA, which I have (http://www.opektech.com/RubberDuckAntennas.html) and then one of the SMA remote clip mounts: http://www.opektech.com/Small_Clip_Mounts.html Try the clip-on mount attached to the top of your pack. Obviously you'll have to duck a lot in the woods. BTW, that Opek 15-inch is my favorite HT antenna. The best I've tried short of my monstrous 1/2 wave telescopic connector-destroyer. What did you use for a ground plane? |
|
Quoted: Quoted: Quoted: What frequencies do you want to use the antenna for? VHF/UHF, we were using 146.525 today That's a really bad choice in frequency by the way. Why would you pick 5khz off of the national simplex frequency? Or do they not cover the concept of bandwidth on tests anymore? Easy fella, this isn't the QRZ forums. |