• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
  • Click here to find out how to win free radios from Retevis!

K40 VERSUS OTHER MOBILES

crusader

Member
Jun 19, 2005
59
1
16
southwest england
just wondering how users of the k40 thought they performed against other mobiles on the market...such as the wilson, sirio and the like,i use a 1/4 wave when static but its not very practical for mobile use.i also own the sirio 4000 but it must have a fault as its deaf.how does the good old K40 compare after all these years in production?
 

I think if your not running more then 500 pep watts Crusader , the K40s are very good antenna's , they have a cap in them to help with SWR properities , if to much watts are put through the loads the cap will go bye bye and the antenna becomes useless . They are good antenna's all the same. They were once the antenna to use in this hobby until Wilson came out with the 1000s , they were just a better power handling antenna without the problems of having a cap involved. I thought the K40s RXed and TXed very well if not neck and neck with the Wilson's , but the power and ease of installation as well as performance of the Wilson's kind of put the ole K40s in the back seat so to speak and never looked back. Good to see you out here Crusader , it's been a while. Happy Holidays to you.
 
The K-40 was the greatest loaded antenna on the market when it was introduced. It used a larger diameter coil, a long stinger, and had a fantastic quick disconnect. It also matched in very well due to the inclusion of a small capacitor in the base. This capacitor was also the K-40s downfall as it would blow with too much power applied. A letter I received from K-40 said the antenna could safely handle 250 watts, but I know of people running twice that power with no problems.

The engineers (Jim Wilson) at Wilson KNEW the K-40 was the antenna to beat and went after it directly. They built a larger coil, had a longer stinger, and eliminated the capacitor in the base by going with a shunt fed (dc grounded) feedpoint. They also used better materials. This is why the Wilson 1000 beat the K-40 according to Lockheed test reports.

To this day, the Wilson 1000/5000 is superior to the K-40 and any other base loaded antenna on the market! With so many out there, if there was a problem, everyone would be complaining about it!

Barjan took over the CB antenna line and is reported to build the 1000/5000 just as they always have. I have an original 1000 and may cut it open to check it against a late model Barjan version.

If you want a better "loaded" CB antenna, you need to look at a center loaded or top loaded antenna. The only top loaded antennas I know of are the fiberglass (Firestik) type and its MY opinion that they don't work as well as the base loaded Wilsons.

An EXCELLENT center loaded antenna is the Predator 10K made by Kale!!! You can find them here... http://predator10k.net/
Stick with the single coil! There have been enough feedback from owners that the single coil outperforms the double coil.

So, if I was to list the antennas in order of preference, it would be:

#1 Predator 10K
#2 Wilson 1000/5000
#3 K-40

I currently own all three.
 
hey guys,thanks for such great information! i really didnt expect to get such alot of interesting backround on the old k40 / wilson antennas.many thanks Master Chief, and also to you Switch Kit,good to see your still around and merry christmas to you too.all the best from the U.K.
 
I'll go one step further...
in that i never liked the K40...
K40 was never more then the 2ed best antenna..

long before kale came out with the 10K
(now best antenna availible)

K40 was easily getting beaten out by an antenna quite simular to kales and perhaps the antenna that brought about kales 10K
(i think it was called D-2500 tho i forget the maker..in early 80's)

dont get me wrong..
K40 is a ok antenna....but it always suffered against center loaded
antennas and after suffered also to wilson 1000/5000

if you are not looking for as big an antenna such as Kales 10K
(best on market without doubt)

then go with the Wilson 1000 or 5000 (depending on power you use)
but dispite how so many say they hear little if any difference between the Wilson 1000/5000 and Kales center load 10K

i know only thise who have not tried both antennas out can say that (or those who do not know how to test antennas fully)

for both local and skip conditions favor greatly Kales 10K
problem for many is its size

Merry Xmas and Happy Holidays to ALL !!!!
 
the only time i saw a 102 inch whip outperform my D-2500

was a friend i had many yrs ago (a bit of a nut)

he stacted on top of one another 4 102 inch whip antennas
(i do not remember how he joined them together though)
he had it guy wired to all 4 corners of his car

with a super simple 4 watts un moded CB he spoke skip madly

ofcourse he got pulled over all the time and given many tickets

car was not safe either in that the antenna swayed to where it hit cars on either side of where he was driving

but once still
damm did he get out with it
 

dxChat
Help Users
  • No one is chatting at the moment.
  • @ BJ radionut:
    EVAN/Crawdad :love: ...runna pile-up on 6m SSB(y) W4AXW in the air
    +1
  • @ Crawdad:
    One of the few times my tiny station gets heard on 6m!:D
  • @ Galanary:
    anyone out here familiar with the Icom IC-7300 mods
  • @ Crawdad:
    7300 very nice radio, what's to hack?
  • @ kopcicle:
    The mobile version of this site just pisses me off