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Hi

Does anyone have detailed specs to build a home brew dipole or similar to use for New Zealand CB frequencies:26Mhz
I wish to build my own antenna and favour the dipole type to begin with. I used gear for the 27Mhz CB band years ago in RSA and am having a hard time finding homebrew antenna info for new zealand CB conditions.
Frequency range -26.330Mhz up to 26.770 Mhz (ch1-ch40)
Also some names of NZ retailers to get base station antennas / Radios info & prices from etc.

thnx 4 a great site! wish I had it 20 yrs ago...while dx'n the 11m band using hard to get knowledge & gear.

Hi there,
Do you mean like a horizontal sort of dipole aerial?

Regarding retailers in NZ that sell CB radios and aerials, it's a very short list these days.
The last CB aerial I bought, I imported from MobileOne in Aussie and it was not cheap at all.
About the only companies I'm aware of that still sell CB radios (these being AM only sets) in NZ are Mobile Systems in
Tauranga and Radio Rentals in Auckland.

Hope this is of some help.

Hi Mike

Thanx for your reply. Yes I meant a horizontal dipole antenna . I have in the meantime after my original post built a homebrew 26Mhz verticle quarterwave antenna from scrap copper tubing. Its a copy of an 27Mhz avanti verticle dipole sold years ago in RSA.pity I cant post a pic for your perusal.
I used the same overall design but tuned it to 26Mhz specs and added a few modifications like a 4:1 balun (also homebrew). Ive also bought a 26mhz 40ch ssb base radio off trademe and got a windom antenna from the seller which I installed north/south and it works far superior to my own verticle antenna mentioned above especially on the ICOM receiver I am using.I am planning to add another east /west windom to the same antenna system in the next few days to get 360 degree coverage. Not sure yet if the swr will remain as good as it it now 1:2 but am keen to find out.
Thanx for all your valued assistance.

mike

Ps: any idea on how the 27mhz radios are converted to 26mhz and vice versa? I have a 26mhz Uniden washington 40ch ssb base radio but I also have a 27mhz uniden grant 40ch ssb radio. I have not yet inspected the circuit boards of both radios to compare and figure it out but will get to it after the windom mods are completed. Its pointless Tx'n on 27mhz in NZ so Id like to convert the 27mhz grant to 26mhz.


Thanx for all your valued assistance.

mike

You already have the lengths of you 2 elements, ( 2 elements each a 1/4 wave long) ad one to the center and the other to the screen of your feed line. hang it horizontal/vertical/ inverted v formation. distance between toe elements, +/- 5 cm (2")

just do a search on the net for any 11mtr 27mhz antennas then for 26mhz make the lengths a couple or three inch longer..

most 5/8th wave 27mhz antennas will SWR around 26.5 to 28mhz.. all below 1.1:5

Buy or borrow a copy of the ARRL antenna handbook all the calcultions you willl need are in there.
Cannot understand why you would want a horizontal dipole for CB in NZ as all antenna are verticle, you are setting yourself up for up to a 40dB loss in reception unless you intend to use for skip? where the recieved signal loses much of it orientation due to repaeated skywave bounce. IMHO you are probably better off with a 1/4 wave ground plane aerial, there is a lot of inflated performance figures qouted for 5/8 aerials that dont pan out when compared to a properly set up 1/4 wave.

Graeme

Did you find your answer on the length you needed? Around 9' 2" should get you there for 26Mhz. Make it longer so you can fold it back for tuning. If you can find a 10 meter convertible radio like the export galaxy, or other such radios you will be able to do what you are asking. My old DX88HL works from 25.615 through 27.855 (working by memory here). Look for that sort of radio.

This antenna may be what you require, simple to build and relativly easy to install. http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=12938 substitute in the frequency you require.

Graeme