Does anybody have any good ideas for a good cb antanna setup in a feller buncher? I have tried different magent mounts and have stuck them on the inside of the cab but with crappy results. When I need to get out I put the antanna on the roof and it work ok. Iwould like it to work good all the time. Anyboby have a better idea?
snowpeke, timbco factory mounts a 10" rubber antenna behind the cab close to the fire extinguisher bottle upside down, basically mounted to the bottom of the roof. i don't know how the reception is but why would you want to listen to that crap anyway isn't that the best part of running a buncher? being away from everyone not dealing with the trucks and the drama on the landing? i can guarantee the skidder operators are blaming you for there lack production, piles to big, piles to small, buts not pointed exactly to the trail, buts on stumps, crossed up top!!!! this set-up is also used on timberjack and tigercat skidders usually in front of the windshield upside down mounted to the bottom of the roof...............theironoracle
Thanks for the reply theironoracle the 10 inch antanna is for the fm radio. Iam just trying to get better reception for the cb radio. Yes I do not listen to the landing talk. I work with another buncher and we run on a different channel. Great comments on piles to big to small, I try to make it good for the skidders.
I sent you a PM, did you get it?
Yes I got it. I have done business with him. Great idea.
Drill-less method to find that reception sweet spot on your machine: Mount your antenna on a mounting bracket using all the insulators that your antenna calls for, (flat or 90* bracket depending on your overhang or flat lip of grounded metal). Use a decent "C" clamp and clamp the bracket tightly to the overhang. This lets you move it around in different locations or even angles before you break out the cordless drill. Just make sure the two surfaces are clean AND DRY. Remember to check your standing wave to ensure your cb has a chance for a long-life. I had a Firestick antenna upside down under the front overhang on our 2520 Timberjack years ago just because the hole was there already. Worked pretty good. Didn't need a spring that way either, and protects the wires. I moved my music radio antenna (10"rubber) outside the cab on my 325D because if you couldn't see the Radio station tower, the reception sucked. Cat puts them inside so they wouldn't have to warranty the antennas. Guess they get broke off. lol. Anyway, I drilled out the hole in a cb mounting bracket to fit the radio ant base, and clamped it to the rear overhang along with the rest of my antennas (The rest are all mounted permanent). Still haven't drilled the radio bracket mount holes....:tong
I have sometimes done work for a radio shop and here is my take. When you mount an antenna upside down on a machine or anywhere near vertical metal (basically any time it is not on the flat roof of a car) the standard length antenna will become very poorly matched. (High SWR). The length will need to be changed a great deal more than the few inches that normal tuning would be. One time I had a customer who wanted a short CB antenna mounted on the mirror of one of those Ford van-type motorhomes with the sleeping area over the driver and passenger seats. Even with the stainless steel whip bent away from the body it was still only a few inches from the metal skin. I used an analyzer setup so I could see exactly where the sweet spot was in frequency and how far it was to get it where I needed it. Once I did, it worked beautifully, but it took some time and energy to get there. I can't remember if it was shorter or longer than standard but I want to say shorter. If you spend the time to get the SWR as low as possible your performance will be much better than if you just go with good enough. Also the lower the frequency (CB is about the lowest of any radio you guys are likely to use) the more interaction it has with the metal surrounding it. But to tune your antenna length with just a radio and SWR meter when there is metal interaction around it is going to take a lot of time and patience.
Is it really a CB? No one uses CB in northern BC anymore. Everybody up here uses VHF/FM, 149-175 Mhz if I remember correctly. I think the US uses slightly different freqs. I have seen those antennas mounted inside the cab on bunchers and they work fine for the range that they need.
Everyone in the US still uses CBs.
BDFT I think the VHF radio is strictly a BC thing, everyone down here uses CB's. Most logging companies in this area have gone to cell pnones, other than Weyerhaeuser who maintains a large 49Mhz system for them and contract shovels. A few companies here and there have their own lowband, VHF or UHF company radio systems but most of the conversations are "call me on my cell when you get reception". I used to install a lot of company radio, cell phone, and CB installs for loggers and road builders back in the 90's but its far and few between now.
You might consider going to hand-held vhf radios like a Motorola CP200. They are 5 watt, just like CB, but we've always been able to reach farther with them then we ever had with a CB. Advantage is no antenna mounting. I have a CM300 mounted in my TimberPro but all of our log cutters carry CP200s in a chest pack. I never have a problem reaching them. My antenna is mounted just on top of the roof. The whip bent right at the base the first day, but is still making a connection. I can reach for miles with my radio.
I wanted to add some info to this thread. I am now back to working as a radio mechanic, that is, I fix, install, maintain and do anything to them. We don't install a whole lot of radios on equipment but we have the equipment to analyze antenna systems and this way we can make adjustments intelligently. I just finished installing a VHF radio in a D5M used for fire service. Basically it has to be set up with full forestry guards and anything that is less than 3/4 inch thick will be torn off by trees and brush. Therefore the antenna has to be installed over the engine somewhere and the power reduced so as not to fry the operators brains when transmitting. In this case I mounted it upside down to the big welded nut that is used to lift the plate off the top of the sweeps. This was not great because it was parallel to the exhaust pipe and pretty close. It did not match on any frequency. After much trial and error, I found that if the mounting plate was bent forward about 30° and rotated to the left about 20° I got a pretty good match across the entire band. It was very critical. If I moved it a little bit it would throw the whole thing off because the exhaust and the front sweeps are surrounding it. I also had to cut the whip a bit shorter than normal. Of course one additional problem is that forestry/fire uses frequencies from the 151-174 MHz range (CB is 27 MHz) which is a wide range and is challenging for an antenna in a normal configuration. All this is made possible by using an SWR analyzer rather than a SWR meter and transmitting and trying. The analyzer displays the response of the antenna across the whole range you are testing, all at once, in a curve on a graph, so you can look and see what effect your adjustments are having as you go along. All this to say that with equimpent, every installation is different and challenging, but it can be done if you are patient.
For best result on transmit and recieve on equipment would prolly be the 102" stainless steel whip. The are almost endestuctable and work great. Ive been on jobs before where cb radio came in handy and used the whip on dozers and trackhoes and worked flawlessly. They are kinda big but nuttin will work any better and last as long.
102" is the full natrual length of an antenna for CB. Everything else is a compromise. They make it work by installing coils at some point along the antenna to transform the impedance (usually at the bottom). Sometimes the antenna itself is a coil such as Firestik, stock Peterbilt antennas, and many others like them. As long as they can be tuned to match the frequency they will work and work pretty good. But the longer the overall length of the antenna, the better it will work. The kicker is that a nice long antenna that is broken off will not work nearly as well as a short compromise antenna that is still intact. In the woods around here, a 102" whip on a piece of equipment would not last five minutes. That is why I encourage short antennas that are tucked in among the metal of the machine even though they are hard to get tuned. If they stay unbroken they will continue to work.
We started using the antenna from the proper frequency hand held two way screwed right into the back of the radio. You can get a small adapter from your radio shop straight or 90 degree. It works awesome, no more cords wrapped around things or cut from being slammed in the cab door, no more magnets. Reception is about 75% as good as before. With a CB put it just behind the front window and the worst thing youll have to do is swing the machine to point to the other guy.
With a CB, that is OK, but do not do it with a commercial radio over about 10 watts or the amount of radio waves in the cab will be scrambling your brains and everything else....
Comercial radio's are the only thing we use them on. It can't be any worse than having the large antenna in the cab with you.
We don't mount full size antennas inside the cab either, you need to get all that power away from the operator. Like I was saying earlier, on the dozer with sweeps we still turned the power of the radio down a bit because it is right in front of the operator. Not as good as getting it up above the roof, but some distance is better than no distance. The eyes and reproductives are lacking in blood flow and suffer the effects of heating more rapidly than the rest of the body, so we try to maintain a degree of separation. In cab antennas are just the opposite of this which is why I say, limit to hand held power (5 watts) or maybe a little bit more since it isn't being held right against the head, but don't sacrifice health and safety for operational convenience.