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K40 Antenna Rant
- Thread starter Mudfoot
- Start date
You need to read my posts more carefully. I didn't mention using the trunk lip gasket on the roof, as you imply.
It's not a 3 way mounting antenna out of the box. If you want to roof mount, you either buy the donut or fabricate one.
I stand by my original posts. It has a lame roof mounting scheme. The company has went to shit. I'm not as ignorant as you think I am.
I'm glad you enjoy your K40.
It's not a 3 way mounting antenna out of the box. If you want to roof mount, you either buy the donut or fabricate one.
I stand by my original posts. It has a lame roof mounting scheme. The company has went to shit. I'm not as ignorant as you think I am.
I'm glad you enjoy your K40.
Lets end this shall we?
TOSE, 42 is allowed to have his own opinions on the equipment he has used, as are all members of the board, including you.
This thread IS about an antenna, not about who is better qualified to install an antenna, personal issues, etc.
If you want to provide a positive report on the antenna, please go ahead, but also please do not waste space ranting about another member's experience.
73
Jeff
TOSE, 42 is allowed to have his own opinions on the equipment he has used, as are all members of the board, including you.
This thread IS about an antenna, not about who is better qualified to install an antenna, personal issues, etc.
If you want to provide a positive report on the antenna, please go ahead, but also please do not waste space ranting about another member's experience.
73
Jeff
Sorry if I came across that way, totally not my intention, I was just trying to pass on information that I was given about using the k40 with or without an amp. No more than that pardon me if it seemed so. I am dumber than a box of rocks when it comes to cb/ham radio. I install cell site equipment for a living and that's what I know. I use these forums just like every other joe for information that may help I'm my quest to talk on a cb lol. I am going to put a sign up at my house that says no cell phones allowed!! God bless all and have a great day.
The shorter the whip is, the larger the base coil must be to make it resonant, and therefore more loss and less efficient radiated energy it will have. Sirios have the longest whips, Wilsons are the next longest, and the K40 is shorter by a fair measure. Keep in mind, that a 1/4 wave steel whip has no gain; it has unity gain. No mobile antenna has gain; they have unity gain (1/4 wave) or less with any base loaded antenna.
It really has nothing to do with what antenna one fancies; it is either loss or more loss with a less efficient antenna choice. Height is might even with mobile antennas. The laws of RF physics are just as much at work with a K40 as a Sirio or Wilson is. But the design of the Sirio and Wilson are just better than the K40. Just can't beat the laws of physics. No one - or no antenna - can.
It really has nothing to do with what antenna one fancies; it is either loss or more loss with a less efficient antenna choice. Height is might even with mobile antennas. The laws of RF physics are just as much at work with a K40 as a Sirio or Wilson is. But the design of the Sirio and Wilson are just better than the K40. Just can't beat the laws of physics. No one - or no antenna - can.
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My stepfather's K40 seems to work just fine. I wouldn't say it is better than my Wilson 1000 but I don't know if it is any worse either. I'd think that being only a few inches (5") in height difference they would be pretty darn close in performance on the local. I think that DX would be where one may see any real difference. Even that wouldn't even be too much. Build quality may or may not be another issue, and one I can't speak to. I believe that Wilson antennas has also been bought/sold to another company and had declines in quality control. I know my stepfather's coil pops off on real bumpy roads, but it has to be at least 10 years old and hit every tree in the north Maine woods. I think that it just needs a little tweak of the locking mechanism inside the bottom end of the coil. When the coil is on, SWR is still very low. My Wilson 1000 has also been through the ringer and isn't without its own few issues. I have had to disassemble it and clean all the connection points to get my SWR back down after 2 years of use. Both are decent antennas. The K40 just isn't as popular anymore. Its like Reebok or Nike, or Ford/Chevy/Dodge. Sure there are plenty of opinions but they all have their strong points and weak points. I don't think that any are really "better" than the other.
I NEVER had any problems installing it (other than fabricating a seal). I'm saying: I don't much care for the mounting scheme as compared to other roof mounts antennas.
I could go into great detail as to why, but I don't feel it's worth the time. I believe other hobbyists that have installed various antennas, are able to see the difference for themselves.
The antenna was/is popular, since it was/is easily installed by most inexperienced users. The clever matching system helped to ensure an easy tune, as well. I like the antenna when used as a lip mount. I just don't like it's roof mount application.
The K40 has a lousy engineered design for roof mount applications. Anyone with junior high shop class experience can see the K40's obvious weaknesses, when compared to other roof mount designs.
Wilson's have issues as well, especially since they changed hands. Most SWR problems I've seen, are caused by users over tightening the coil.
Most members on this forum are aware that I tend to avoid emotional attachments to my equipment.
I could go into great detail as to why, but I don't feel it's worth the time. I believe other hobbyists that have installed various antennas, are able to see the difference for themselves.
The antenna was/is popular, since it was/is easily installed by most inexperienced users. The clever matching system helped to ensure an easy tune, as well. I like the antenna when used as a lip mount. I just don't like it's roof mount application.
The K40 has a lousy engineered design for roof mount applications. Anyone with junior high shop class experience can see the K40's obvious weaknesses, when compared to other roof mount designs.
Wilson's have issues as well, especially since they changed hands. Most SWR problems I've seen, are caused by users over tightening the coil.
Most members on this forum are aware that I tend to avoid emotional attachments to my equipment.
My experience and opinion
There's a cb'er 30 miles from me that uses a K40 mag mount with his 2 pill in his mobile. He likes his setup and it works fairly well I might add.
I too have a K40 mag mount antenna that I used for six months. I owned a K40 back in the eigthies on my sports coup(looked cool sort of). The only problems I've had with my K40 was that when it got wet the swr went up until it dryed out. The K40 whip was too short for 11 meters 25 years ago and my K40 antenna's whip I own now is too short. I always had to adjust the whip to where the Allen screw would barely catch the whip. Also,my K40 would pick up my iPhone 5 screen noise. It doesn't pick up the noise now with the Sirio in almost the same mounting spot. I did move the Sirio back back on the roof just a few inches more. Now the only way I can hear my iPhone noise is if I place the phone out the window near the roof line.
I found out about the Sirio Performer PL5000 several months ago,did my research,and realized that I might benefit from purchasing one in which I did.
In my personal opinion the Sirio outperforms the K40 hands down plus the Sirio has weatherproof rubber bushings and seals to keep the water outside where it belongs.
There's a cb'er 30 miles from me that uses a K40 mag mount with his 2 pill in his mobile. He likes his setup and it works fairly well I might add.
I too have a K40 mag mount antenna that I used for six months. I owned a K40 back in the eigthies on my sports coup(looked cool sort of). The only problems I've had with my K40 was that when it got wet the swr went up until it dryed out. The K40 whip was too short for 11 meters 25 years ago and my K40 antenna's whip I own now is too short. I always had to adjust the whip to where the Allen screw would barely catch the whip. Also,my K40 would pick up my iPhone 5 screen noise. It doesn't pick up the noise now with the Sirio in almost the same mounting spot. I did move the Sirio back back on the roof just a few inches more. Now the only way I can hear my iPhone noise is if I place the phone out the window near the roof line.
I found out about the Sirio Performer PL5000 several months ago,did my research,and realized that I might benefit from purchasing one in which I did.
In my personal opinion the Sirio outperforms the K40 hands down plus the Sirio has weatherproof rubber bushings and seals to keep the water outside where it belongs.
Attachments
There's a cb'er 30 miles from me that uses a K40 mag mount with his 2 pill in his mobile. He likes his setup and it works fairly well I might add.
I too have a K40 mag mount antenna that I used for six months. I owned a K40 back in the eigthies on my sports coup(looked cool sort of). The only problems I've had with my K40 was that when it got wet the swr went up until it dryed out. The K40 whip was too short for 11 meters 25 years ago and my K40 antenna's whip I own now is too short. I always had to adjust the whip to where the Allen screw would barely catch the whip. Also,my K40 would pick up my iPhone 5 screen noise. It doesn't pick up the noise now with the Sirio in almost the same mounting spot. I did move the Sirio back back on the roof just a few inches more. Now the only way I can hear my iPhone noise is if I place the phone out the window near the roof line.
I found out about the Sirio Performer PL5000 several months ago,did my research,and realized that I might benefit from purchasing one in which I did.
In my personal opinion the Sirio outperforms the K40 hands down plus the Sirio has weatherproof rubber bushings and seals to keep the water outside where it belongs.
ive use k40s years ago . mine were mag mounts though. but they worked good at that time
early 1990s??? later i started using wilsons and seen a slight increase in tx/rx probaly
due to the wilson having a 62 inch sting and k40 was only 54 [i think]. now i DO agree
that they should include the rubber gasket in thier roof mount and just charge a few extra dollars . jmo
I always used the magmount with K40's. Sirio just has a better solution to moisture intrusion protection.
The K40 is a good antenna if you are barefoot or run under say 200 watts and you are trunk mounting it or doing the mag mount. I used to be able to buy them for 38 bucks. Today they run as much as a Wilson 1000 or even more. That said your money would be better spent on a Wilson 1000.
My Wilson mag mount's pl259 just messed up so I slapped on an old K40 trunk mount. Seems to be working great, i'll probably run it for several weeks until I get the Wilson fixed.
My Wilson mag mount's pl259 just messed up so I slapped on an old K40 trunk mount. Seems to be working great, i'll probably run it for several weeks until I get the Wilson fixed.