Charlie Tango 11m DX Radio Group Forum
Would you like to react to this message? Create an account in a few clicks or log in to continue.


Welcome to the Charlie Tango DX Group. The home of ALL things Radio - CB, 11m DX, Amateur, PMR446, PLD, Network and Data. We welcome all radio enthusiasts of all knowledge levels. Join today and claim your own unique World Famous CT Call-sign
 
HomeEventsCalendarFAQLatest imagesSearchRegisterLog in

11m Winter Challenge, 1st December - 31st March. Details in DX Lounge. Join us now..........
Navigation
Useful Radio Sites
Log in
Username:
Password:
Log in automatically: 
:: I forgot my password
CT Bill Board





Views This Year
All Time Views
Classified Adverts

Latest topics
» Call sign request
Cobweb help please  Icon_minitimeToday at 6:02 pm by S Ramsey

» CW contacts for dummies
Cobweb help please  Icon_minitimeToday at 2:50 pm by Ivy Mike

» Callsign Request (Issued)
Cobweb help please  Icon_minitimeToday at 1:12 pm by John123

» CRT SS6900V
Cobweb help please  Icon_minitimeToday at 12:33 pm by Mavic2Pro

» South Coast PMR net report
Cobweb help please  Icon_minitimeYesterday at 11:16 pm by Sharpshooter

» 11m winter challenge
Cobweb help please  Icon_minitimeYesterday at 9:44 pm by Kaosss

» Southern and Southcoast Net
Cobweb help please  Icon_minitimeYesterday at 8:37 pm by Razz229

» 11m conditions
Cobweb help please  Icon_minitimeYesterday at 7:08 pm by John123

» CRT ss9900 cooler
Cobweb help please  Icon_minitimeYesterday at 10:24 am by Razz229

Keywords
frequency radio 2022 SS6900 Calling anytone display ss9900 yaesu callsign ALINCO Mckinley power lincoln Sirio 9900 sign president 6900 chart antenna call Mobile division list Baofeng
QRZ Database

 

 Cobweb help please

Go down 
4 posters
AuthorMessage
26ct954
Major contributor
Major contributor



Call Sign : 26-CT-954, M7PLD..
Posts : 242
Times Thanked : 2
Join date : 2020-11-27
QTH or Location : Ellesmere Port
Equipment Used : icom 718,cobweb,anytone 667,
Age : 68

Cobweb help please  Empty
PostSubject: Cobweb help please    Cobweb help please  Icon_minitimeWed Jun 09, 2021 5:24 am

Just bought a second hand 7 band version,, mcr cobweb having a issue with the  Swr  really high on  20m, its only low at the  moment 10ft till i sort this out, its a twin wire i noticed the wires are twisted can this be my problem,, i am using a external ATu and that get the  numbers low any ideas please... Forget to mention its only a few months old...
Back to top Go down
View user profile
Bean
Major contributor
Major contributor



Posts : 214
Times Thanked : 6
Join date : 2019-06-29

Cobweb help please  Empty
PostSubject: Re: Cobweb help please    Cobweb help please  Icon_minitimeWed Jun 09, 2021 10:00 am

Is it to low in frequency ? as in the elements are to long , NC has posted about this before with mcr cobwebb ,all I did with mine was to have more of the wires in contact with each other on each support pole thus shortening the element without any cutting . If its just high all over on 20m then maybe the element has broken or something at the shorting point.
Back to top Go down
View user profile
Northern Crusader
Major contributor
Major contributor



Call Sign : M0GVZ / 26CT1760
Posts : 481
Times Thanked : 32
Join date : 2019-11-13
QTH or Location : IO94SA
Equipment Used : Icom 7300, TS480, President McKinley, Albrecht AE6110, CRT Mike
Age : 52

Cobweb help please  Empty
PostSubject: Re: Cobweb help please    Cobweb help please  Icon_minitimeWed Jun 09, 2021 5:19 pm

The wires being twisted don't matter.

I used to own an original made by the original designer Steve Webb. I replaced it by one made by a guy who sold on Ebay under the username MCR666 because Steve Webb stopped making them when he retired.

At the time this guy was the only one making them. When I got it it was instantly obvious it wasn't the right size. Sure enough when I put it up and got the antenna analyser on it the resonant frequency was above the ham bands. Unfortunately because of the lengths of the spreaders there wasn't enough gap between the elements to be able to lengthen them enough to get the SWR down.

I offered to help this guy and went to his house with some parts from my geniune one so he could get measurements and address the problem. He took me to where he made them which was in his bedroom. He had a metal frame bed and was building them and tuning them mounted on one of the poles in the corner of the bed so of course the antenna was capacitively coupling to the metal bed frame barely a foot below it and making it appear electrically longer than it was which is why it was too small. Unfortunately despite his bleating about his knowledge of amateur radio he didn't even think there would be a problem and refused to accept there was. And as far as he was concerned because the rig internal ATU could match it it was fine, even though the original needs no ATU other than for the top end of 10m.

The bloke is an absolute arse who was more interested in bragging about his CD and DVD copying rigs and how many thousands of pounds he was making from pirated vehicle manuals he was selling on Ebay than addressing the issues with the Cobwebs he was selling.

So unless MCR666 has woken up, smelled the coffee and altered his design then none of the ones he sold either directly or through LAM are the right size and there's not enough slack in either the spreaders or the wire elements to be able to extend them enough to correct that.

43CT016 and 26ct954 like this post

Back to top Go down
View user profile
26ct954
Major contributor
Major contributor



Call Sign : 26-CT-954, M7PLD..
Posts : 242
Times Thanked : 2
Join date : 2020-11-27
QTH or Location : Ellesmere Port
Equipment Used : icom 718,cobweb,anytone 667,
Age : 68

Cobweb help please  Empty
PostSubject: Re: Cobweb help please    Cobweb help please  Icon_minitimeWed Jun 09, 2021 5:48 pm

Thanks for all the info, i didn't pay much for mine £80 which was a bargain will have to keep using the external Atu too keep things safe...
Back to top Go down
View user profile
Bean
Major contributor
Major contributor



Posts : 214
Times Thanked : 6
Join date : 2019-06-29

Cobweb help please  Empty
PostSubject: Re: Cobweb help please    Cobweb help please  Icon_minitimeWed Jun 09, 2021 7:50 pm

Mine was the mcr666 5 band version that I got when I first got my licence in 2016 ( and still believe the cobwebb/cobweb is one of the best antennas for the newly licenced to start with for the higher HF ) 10>17m were no problem and worked out the box as it were but the 20m element was to low in frequency and as I said before an extra cable tie on each support arm to shorten the electrical (RF) length sorted that.
Back to top Go down
View user profile
The author of this message was banned from the forum - See the message
Northern Crusader
Major contributor
Major contributor



Call Sign : M0GVZ / 26CT1760
Posts : 481
Times Thanked : 32
Join date : 2019-11-13
QTH or Location : IO94SA
Equipment Used : Icom 7300, TS480, President McKinley, Albrecht AE6110, CRT Mike
Age : 52

Cobweb help please  Empty
PostSubject: Re: Cobweb help please    Cobweb help please  Icon_minitimeFri Jun 11, 2021 2:30 pm

It's a shame he was such a dick about it and didn't address the issues because the build quality was actually quite good and because of how he did the spreaders it actually had fewer points of failure than the original.

I ended up using the wires and junction box with it's supporting arm from my original one on the spreaders and centre plate of MCR666's in the end. The fact it lasted several years and several moves from my house to a farm a few miles away where my radio club does field day when it was used as an antenna for a second station pays testiment to the build quality.
Back to top Go down
View user profile
Sponsored content





Cobweb help please  Empty
PostSubject: Re: Cobweb help please    Cobweb help please  Icon_minitime

Back to top Go down
 
Cobweb help please
Back to top 
Page 1 of 1
 Similar topics
-
» Cobweb query
» Cobweb purchase
» Cobweb height
» Any body got a cobweb antenna
» Cobweb and 2m/70cm on the same pole.

Permissions in this forum:You cannot reply to topics in this forum
Charlie Tango 11m DX Radio Group Forum :: Help and Discussion Forums :: Antenna Discussion-
Jump to: