My primary hobby is off roading with my Jeep club and CB radio communications are essential to us. Most of our radios are standard Cobras, Unidens, etc. that have been peaked and tuned at the local CB shop and running on Firestik type antennas. No one runs amps or anything special as far as I know.
As a former military communicator, I think it would be smart to carry a "field CB and electrical first aid kit" of sorts. Sorry for the corny name but it illustrates what I'm getting at.
The basic kit should be small enough to carry at all times in the glove box or center console of a Jeep and not duplicate the basic tools like screwdrivers and such that all four wheelers would carry anyway. Basically vehicle spare fuses, relays, electrical tape, 16 gauge wire, test leads, mini-multimeter and a small SWR meter. Perhaps an extra mic if space wasn't an issue.
The next step was including pre-cut lengths of wire to build simple, static wire antennas to improve the transmission in a bad situation or to replace a broken whip. In the military we called these "field expedient" antennas and all good communicators carried pre-cut wires with sufficient insulators and ties for various types of wire antennas.
The antennas I wanted to pre-cut were a vertical whip replacement (1/4 wavelength), a simple inverted "L" (1/4 wavelength vertical and 1/2 wavelength horizontal) and a sloping, 1/2 wavelength long wire. I specifically chose simple antennas that I could teach other club members to build on a dark and rainy night in the woods without messing with baluns or having long coax feeds to deal with.
Using .234 to compute a 1/4 wavelength for for the CB spectrum (25 - 27 MHz) shows it should be between 106 to 111 inches but my web research indicates that all commercial CB whip antennas are actually or are based on 102 inches. My math shows a 1/2 wavelength should be 212 - 222 inches or should it be 204 inches? Is my math wrong or is something else the reason for this? I know in a field situation it shouldn't make a huge difference but the difference is enough to bother me, especially if I'm going to teach a class on it.
Would you choose different wire antennas for non-technical people to use on a cold and rainy night in the Southern Piedmont area? This area is low mountains with sandy clay soil that is generally moist and has a high mineral content in the mountain areas. If so, which ones and why?
If your 12v radio was mounted in your Jeep and was grounded properly, would you still need to run a grounding wire to actual earth if you started attaching longer wire antennas to it? Would you run the grounding wire from the coax shielding where the antenna begins to actual earth or just to a good ground on the frame?
What else would you add to your kit and why? I do plan to test and trim the antennas with my SWR meter before I pack it but I'd like to have the correct measurements for class purposes.
Thank you for your thoughtful answers and I look forward to your input.
Simple Wire Antenna Construction for Field Use
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I wheel too...as do a few here like Thumper. Although my rigs are more simple trail rigs...not crawlers like Thumpers. His tires dwarf my 33's!
Actually, I simply keep an extra antenna or two in the TJ as they don't take up much room laid down. And I only use Everhardt Superflex Tiger TSM series for wheelin'...as do the majority of my friends. They'll out perform the Firestiks hands down and are much more forgiving to off road abuse IMO. Some folks still run 102" SS whips, too...although some clubs have banned them. I also keep an extra mic for me in my console. I have loaned that out, too.
I only carry spare quick disconnects & solderless connectors (in my general electrical kit), some 12 & 14 gauge wire, some misc. SS nuts and bolts, etc. I have on board air too. No welder, but we all wheel together and nobody is left behind. Recovery gear...same as Thumper, including winches, straps, shovels, tools, some spare parts, etc.
But there is plenty of room in CJ's, YJ's, and TJ's for an extra antenna, mount (clamp or otherwise), and coax. I too don't run an amp (yet) in the TJ. When I trailer the TJ though, my truck has plenty of radio equipment (including amp) in it. And I keep an extra antenna (or two) in there, too. I'll throw my SOTT-5' Tiger on there and have nothing short of a rolling base station.
I guess I'm not really following the logic of keeping stuff to make a wire antenna in the rig? Heck, if someone breaks an antenna I loan them one of my other TSM's in the rig. Nobody has broke one of them yet. Most of the guys I wheel with can care less about making antennas, just wheelin' and gabbin' on the radio. And I'm like you, most of the guys I wheel with look to me to keep thier radio stuff going.
Actually, I simply keep an extra antenna or two in the TJ as they don't take up much room laid down. And I only use Everhardt Superflex Tiger TSM series for wheelin'...as do the majority of my friends. They'll out perform the Firestiks hands down and are much more forgiving to off road abuse IMO. Some folks still run 102" SS whips, too...although some clubs have banned them. I also keep an extra mic for me in my console. I have loaned that out, too.
I only carry spare quick disconnects & solderless connectors (in my general electrical kit), some 12 & 14 gauge wire, some misc. SS nuts and bolts, etc. I have on board air too. No welder, but we all wheel together and nobody is left behind. Recovery gear...same as Thumper, including winches, straps, shovels, tools, some spare parts, etc.
But there is plenty of room in CJ's, YJ's, and TJ's for an extra antenna, mount (clamp or otherwise), and coax. I too don't run an amp (yet) in the TJ. When I trailer the TJ though, my truck has plenty of radio equipment (including amp) in it. And I keep an extra antenna (or two) in there, too. I'll throw my SOTT-5' Tiger on there and have nothing short of a rolling base station.
I guess I'm not really following the logic of keeping stuff to make a wire antenna in the rig? Heck, if someone breaks an antenna I loan them one of my other TSM's in the rig. Nobody has broke one of them yet. Most of the guys I wheel with can care less about making antennas, just wheelin' and gabbin' on the radio. And I'm like you, most of the guys I wheel with look to me to keep thier radio stuff going.
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CharlesW
When we wheel as a club we share gear and no one gets left behind. Everyone's been strapped to the trail head at one time or another and no ever gets further away from the group then a good whistle or Jeep horn can be heard even if the radio stops working. That's not the situation I'm thinking about though.
Many of our members wheel solo while hunting, fishing, geocaching or just nature observing between events and it was those solo situations I was thinking of.
That late afternoon when your rig breaks down on a forest service road while you're out without any other rigs on your way back from your favorite fishing hole, out of range of any cell phone towers. Not everyone wheels solo but many do from time to time.
That situation doesn't apply to everyone but some folks could be considered higher risk wheelers since they wheel often without a club around. I think that in that situation, a bit of knowledge and an extra 100 inches of wire may help you reach some random driver listening to channel 19 on the highway down the valley.
Many of our members wheel solo while hunting, fishing, geocaching or just nature observing between events and it was those solo situations I was thinking of.
That late afternoon when your rig breaks down on a forest service road while you're out without any other rigs on your way back from your favorite fishing hole, out of range of any cell phone towers. Not everyone wheels solo but many do from time to time.
That situation doesn't apply to everyone but some folks could be considered higher risk wheelers since they wheel often without a club around. I think that in that situation, a bit of knowledge and an extra 100 inches of wire may help you reach some random driver listening to channel 19 on the highway down the valley.
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Bozo
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Oh...by the way, welcome to the forum Charles! Great and helpful folks here!THUMPER wrote:231
how is Portland for wheeling to bend or prineville ?
i am in bend alot and have seen some nice trails
not as good as some of the ones i have here but almost .....lol
Thumper, it depends. This time of year they close the majority of trails in the Tillamook State Forest...which is probably one of the closer OHV areas. Spring through Fall though it's okay. A bit too much traffic on many of the trails though for my liking. I'm a bit sick of those things in the Portland area myself though.
There are many places in the Eastern and Central part of the state though. I've only wheeled at Virtue Flats (which is anything but flat!) outside of Baker City (Eastern Oregon). [Please login or register to view this link] is a quick write up from one of my wheelin' friends about it. It is by far one of my favorite places to wheel and camp. I'd recommend it to anyone! Many of the gullys and level 5's would play havoc with full width axle rigs and buggys though.
I know you guys have some awesome wheelin' spots down there, too. I someday hope to take some time and wheel them. There are still many areas up here I haven't hit yet either. Naches in Washington, Evans outside of Seattle, Owhaynees in Idaho, and the BLM lands in Eastern and Central Oregon to name just a few.
My friend Kevin (Dustdriver) has some good links on his site [Please login or register to view this link] you might find helpful. He gets weeks at a time off work and is able to hit many places. If you get time, check out his site and links...especially his photo gallery! Dang! Makes me mad I have to be a working sap!
Sorry Charles...didn't mean to hi-jack your thread.
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231
Cool...that makes sense. Personally, I think I'd have those high risk guys wad up a dipole...already pre-made and tuned. Have them keep fishing line, too...and maybe even a sling shot and large shot to shoot the fishing line high over a tree limb. Many Ham friends I have will do just that...set up a dipole station where ever they might be. Most will be doing it though for the VHF/UHF bands though, which obviously are much smaller than the HF we run. But nevertheless, it can be done with very little space requirement.CharlesW wrote: Many of our members wheel solo while hunting, fishing, geocaching or just nature observing between events and it was those solo situations I was thinking of.
Just my $.02
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CharlesW
As an obviously experienced wheeler and communicator, your two cents is appreciated.
I love the dipole but had discounted it for this application since to raise it 30 feet off the ground would require 35+ feet of coax to feed it and it would also require a balun. That and the need for it to be suspended 30' up from two trees perpendicular to the desired transmit direction on sloped, rocky terrain on a dark and stormy night puts it in the too hard category for non-technical types.
Heck, as a trained field radio operator I always tried the inverted "L" first for temporary installations just because it was simpler and faster to set up in the dark and much easier to incrementally adjust the transmit direction with. For longer term solutions, especially in daylight, I generally built long wire or dipole antennas depending on the terrain and space available.
An inverted "L", though not quite as efficient as a good dipole, has similar gain and transmission characteristics to a dipole but isn't so finicky about how it's erected and is "bottom fed" so doesn't require the long coax, nor does it require a balun. This seemed to be a much simpler bi-directional antenna to erect in an emergency type of situation then the dipole. Not needing 30 - 50' of coax and a balun is a huge space saver IMHO when it comes to kit building.
I love the dipole but had discounted it for this application since to raise it 30 feet off the ground would require 35+ feet of coax to feed it and it would also require a balun. That and the need for it to be suspended 30' up from two trees perpendicular to the desired transmit direction on sloped, rocky terrain on a dark and stormy night puts it in the too hard category for non-technical types.
Heck, as a trained field radio operator I always tried the inverted "L" first for temporary installations just because it was simpler and faster to set up in the dark and much easier to incrementally adjust the transmit direction with. For longer term solutions, especially in daylight, I generally built long wire or dipole antennas depending on the terrain and space available.
An inverted "L", though not quite as efficient as a good dipole, has similar gain and transmission characteristics to a dipole but isn't so finicky about how it's erected and is "bottom fed" so doesn't require the long coax, nor does it require a balun. This seemed to be a much simpler bi-directional antenna to erect in an emergency type of situation then the dipole. Not needing 30 - 50' of coax and a balun is a huge space saver IMHO when it comes to kit building.
