Go Back   Worldwide DX Amateur Radio Forums - Ham - CB - HF - VHF - UHF > Amateur Radio Related > Amateur Radio Antennas


Amateur Callsign Lookup
Enter Callsign:

How would a 11m beam work on 6m with a Antenna tuner?

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 10-21-2009, 11:56 PM
Junior Member
iTrader: (0)
 
Join Date: Jul 2009
Posts: 1
hilifer is on a distinguished road
Default How would a 11m beam work on 6m with a Antenna tuner?


Looking to buy a Yaesu FT-767GX with built In Antenna tuner with 6 meters.....Just wondering how a 11 meter beam would work...
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Worldwide Radio Forum
  #2  
Old 10-22-2009, 12:29 AM
Junior Member
iTrader: (0)
 
Join Date: Jul 2009
Location: 60 Mi S. Houston,Texas
Posts: 13
regencycb is on a distinguished road
Smile 11m beam 6 meters FT767

Quote:
Originally Posted by hilifer View Post
Looking to buy a Yaesu FT-767GX with built In Antenna tuner with 6 meters.....Just wondering how a 11 meter beam would work...

You may run into one problem the FT767 has seperate antenna connectors for HF/ 6m/2 m /440 depending if all modules are installed. The internal tuner only works on the HF antenna connector on 160-10 meters. You will have much improved results with a home brew 3 element beam that is resonant in the six meter band.

SD
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #3  
Old 10-22-2009, 01:50 AM
Senior Member
iTrader: (0)
 
Join Date: Aug 2008
Posts: 336
HiDef is an unknown quantity at this point
Default

It might load up but performance will not be anything like a 6 meter beam.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #4  
Old 10-22-2009, 02:12 AM
Supporting Member
iTrader: (0)
 
Join Date: Apr 2005
Location: Oklahoma
Posts: 3,075
W5LZ is an unknown quantity at this point
Default

Can it be done? I don't know about the tuner's capability so can't say for sure. Very definite maybe. Would it be worth doing, an 11 meter beam on 6 meters? It'd work, but it's probably not worth the effort. Try it and see what happens. Then come tell the rest of us.
- 'Doc
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #5  
Old 10-22-2009, 03:59 AM
Radio Tech's Avatar
Radio Operator
iTrader: (0)
 
Join Date: Sep 2008
Location: North Carolina
Posts: 258
Radio Tech is on a distinguished road
Default

Work? Yes
As a beam ? No
Would work like a omni directional antenna.
The tuner would "tune" the driven element. But the director and reflector would not be in sink.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #6  
Old 10-22-2009, 04:40 AM
Senior Member
iTrader: (0)
 
Join Date: Mar 2005
Location: england
Posts: 1,022
bob85 is on a distinguished road
Default

regencycb is correct, the ft767gx tuner only works on hf, it does not work on the 6/2/70 modules, you will need an external tuner,
11mtr beams don't work very well as a beam on 6mtrs with or without a tuner.
__________________
the blind lead the blind but the enlightened will lead you to the sigma4
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #7  
Old 10-22-2009, 05:08 AM
Captain Kilowatt's Avatar
Administrator
iTrader: (0)
 
Join Date: Apr 2005
Location: Nova Scotia,Canada
Posts: 3,113
Captain Kilowatt is on a distinguished road
Default

You would do better with a simple 1/4 wave groundplane on 6m than you would trying to use an 11m beam. Any directivity seen would be a result of extra losses in certain directions rather than gain in peak directions.
__________________
Front/back ratio comes from the antenna. Forward gain comes from the wall socket.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #8  
Old 10-22-2009, 08:41 AM
jazzsinger's Avatar
Senior Member
iTrader: (0)
 
Join Date: Jul 2008
Location: United Kingdom
Posts: 236
jazzsinger is on a distinguished road
Default

if its the type of beam the elements telescope on, then it might not be that hard to convert for 6m.thats taking into account you no longer wish to use it on 11m.

for 6m centred on 52mhz you would need to make the driven element about 8.98 feet (2.74m) total length.reflector would be around 9.44 feet (2.88m) and director would be around 8.54 feet (2.60m),if your tubing will telescope into those lengths you've cracked it.

after that the only thing you would have to worry about is spacing between the elements to give the right impedance,trial and error with an antenna analyser preferrably or a swr meter if its the only instrument you have would optomise the beam on the new frequency range.

as others have said though it may be more desireable or easer depending on the 11m beam design to build one from scratch and keep the 11m beam for 11m or 10m or build 1/4 wave gp which is simple and relatively small for that frequency range.

Infact if you made the radiating element of the 1/4 wave gp half the size of the above lengths for the beam driven element,4.49 feet or 1.37m you wouldn't be far out,add 3 or 4 ground wires of the same length at 45 degree downward sloping angle attached to the coax shield and you got yourself a very cheap and very effective 1/4 wave groundplane for 6m.

might be wise to add a little extra to the lengths to allow for tuning the antenna in its mounting location.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #9  
Old 10-23-2009, 01:51 PM
Senior Member
iTrader: (0)
 
Join Date: Feb 2007
Location: n.w pennsylvania
Posts: 601
hotrod is on a distinguished road
Default

Quote:
Originally Posted by jazzsinger View Post
if its the type of beam the elements telescope on, then it might not be that hard to convert for 6m.thats taking into account you no longer wish to use it on 11m.

for 6m centred on 52mhz you would need to make the driven element about 8.98 feet (2.74m) total length.reflector would be around 9.44 feet (2.88m) and director would be around 8.54 feet (2.60m),if your tubing will telescope into those lengths you've cracked it.

after that the only thing you would have to worry about is spacing between the elements to give the right impedance,trial and error with an antenna analyser preferrably or a swr meter if its the only instrument you have would optomise the beam on the new frequency range.

as others have said though it may be more desireable or easer depending on the 11m beam design to build one from scratch and keep the 11m beam for 11m or 10m or build 1/4 wave gp which is simple and relatively small for that frequency range.

Infact if you made the radiating element of the 1/4 wave gp half the size of the above lengths for the beam driven element,4.49 feet or 1.37m you wouldn't be far out,add 3 or 4 ground wires of the same length at 45 degree downward sloping angle attached to the coax shield and you got yourself a very cheap and very effective 1/4 wave groundplane for 6m.

might be wise to add a little extra to the lengths to allow for tuning the antenna in its mounting location.
yes i know a ham that did this very thing also think he may cut the boom also?not sure
youd definately need a anylizer if ya got one it would be worth a try if ya have a little free time on your hands.
__________________
magnum delta force
magnum omega force
uniden grant
cobra 2000gtl
sirio z180
skythumper65dx
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #10  
Old 10-23-2009, 07:41 PM
Captain Kilowatt's Avatar
Administrator
iTrader: (0)
 
Join Date: Apr 2005
Location: Nova Scotia,Canada
Posts: 3,113
Captain Kilowatt is on a distinguished road
Default

In one case it was asked if an 11m antenna could be made to work on 6m with a tuner. The short answer is yes. The tuner will force the antenna to accept power from the transmitter and the antenna will radiate but how well it will radiate is another question. Again in short, the result will not be great but it will be better than nothing at all.

In the other case it was suggested that perhaps the 11m antenna be resized for 6m. In this case the antenna is no longer an 11m antenna and in fact has become a 6m antenna and will work well as long as care is taken to use the proper dimensions. Years ago I salvaged my old Wilson Shooting Star and used the aluminum to make a six element yagi for 6m. It works great,better than the comparable from Cushcraft. In this case I am NOT using an 11m antenna on 6m but rather CONVERTED an 11m antenna into a 6m antenna.
__________________
Front/back ratio comes from the antenna. Forward gain comes from the wall socket.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Crusader 10K, 5 Element Yage Beam Antenna, UP DATE AudioShockwav A1 Antennas 24 10-24-2009 08:47 AM
Interesting reading, datsun66 General Ham Radio Discussion 3 08-16-2007 09:16 PM
Interested in switching over to a beam antenna automan4025 CB Antennas 1 06-03-2007 03:42 PM
Jays I-10K Antenna Feedback RollingRadios A1 Antennas 29 10-02-2004 08:52 AM


All times are GMT -7. The time now is 11:04 PM.


Powered by vBulletin®
Copyright ©2000 - 2009, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.3.2
Worldwide Radio Forum