Home made CB/11M base Antenna - Suggestions & Advice

[JLow75]

Hi All,

I am going to build a vertical polarised base station antenna for CB/11M as it's time for a new project & I have access to all kinds of free/inexpensive stuff , plastic tubing/poles/wire/metalwork/electrical consumables etc etc. Also at my base location I have tried various antennas (some expensive!) without much success for various reasons - so I am now refusing to spend any more money on this hobby, and doing some research I believe I can make an antenna that will perform just as well as most manufactured antennas.

I am a time served technician with over 21 years experience in all aspects of electrical & electronics wiring & build , so there will be no problem with me building anything to a good standard - however it's my antenna theory knowledge that lets me down! - I would like some advice on which type of antenna is most likely to give me the best results for my location

I have researched some home brew antennas & I think the main choices are:

1/4 wave Dipole
Groundplane antenna
Bazooka
J-Pole
inverted V

My location & use details:

I basically live in a heavily built-up area (although it is quite high up on a hill)
The antenna can be mounted anywhere from ground level upto around 20-25 foot in the air (I do have some access restrictions)
no trees - just a gable wall of my house & a flat roof
I get a LOT of noise on 27Mhz in this location, so I want a type of antenna/location that may reduce this if possible.
size isn't too much of an issue, within reason (as long as I can get it in a suitable location on the house)
No DX use - more interested in local stations, up to 20 miles away


If anyone can advise on what antenna would be my best best for the above mentioned criteria that would be great, also any youtube links welcome

Thanks in advance

[Oggy]

I would suggest buy the ARRL antenna handbook and spend some time reading it.
I got many tips years ago from this including rock salt earths and the like.

[JLow75]

I don't want to delv too deep into it - too busy!, just thought I'd see if anyone on here is into homebrew antennas & could suggest the best type & mounting method for local use in a built up area etc

[rizz]

If you get a lot of noise an Omni directional antenna will not be ideal for reception maybe you could make a dipole but angle the bottom element to 45 degrees which will make it directional to a point in that direction, if you put that radial horizontial it will be completely directional in the radial direction, you can then turn it around until you can hear people through the noise at leave it in that position. I have a boomerang and I'm experimenting with Qrm and making the antenna directional for the least noise possible.

[Black_Pirate]

i go for a double bazooka or a loop antenna , although not a omni the loop is simple and can be made cheap...the d.bazooka and t2lt simple and quite effective... googling stealth antennas will throw up some good ideas and on youtube...

[Adriano9966]

Why just the one antenna? If you have the space why not several you could have an inverted v dipole in the attic or even a loop if you wish .
here is a useful video on how to build an unobtrusive groundplane antenna https://www.youtube.com/watch?v=aLgFeTpIX4A

and another useful video of the t2lt coax antenna which you could support with a cheap telescopic fishing pole
https://www.youtube.com/watch?v=Gf8xeq77kkI&t=6s hope that helps have fun with your home brewing

[Oggy]

I don't want to delv too deep into it - too busy!, just thought I'd see if anyone on here is into homebrew antennas & could suggest the best type & mounting method for local use in a built up area etc

A T2lt (coax antenna) seems a good cheap antenna a lot seem to favour these days.

I'll tell you how to build one but......too busy

[bigal68]

I built a homebrew Gainmaster from the instructions from PsiDoc on an earlier thread on here.

For some reason I can't seem to find the thread now, but there is plenty of information on the net regarding this...... and plenty of pictures too.

Couldn't find a 66mm former for the choke at the bottom, so I used some black guttering downpipe from B&Q (68mm diameter).

Seems to work ok, SWR is <1.5:1 from about 26.4 to 28.7ish which does for what I want.

Its taped up to a 10m fishing pole mounted about 6ft off the ground at the back of my greenhouse up the garden, and with no more than a max of 40w out the back of various radio's I have tried, has got me round Europe when the band is open....... so I'm guessing its not a dummy load....

I have tried J-poles with various results. My biggest gripe with these (built using wire and 300ohm feeder for the matching section) is that they all appeared to be relatively narrow banded. I seem to remember that the best I got was about 800khz <2.0:1 SWR...... which wasn't enough really.

I've also tried the bazooka/double bazooka with varying success. I found these to be a bit narrow too, but seem to be variable dependant on the weather, and I couldn't get the SWR below 1.8:1 no mater how I tried. Choke baluns and everything.

Both the bazooka's and the J-poles worked ok, and aren't bad antenna's...... but I still think the the homebrew gainmaster is my favourite

[JLow75]

Thanks for that all, that's great

Yes that's what I'm planning to do, as I have a large loft - make a simple Inverted dipole from wire for the loft & maybe something outside I can support with a fishing pole or plastic tube etc, that would be no problem, then I will compare the loft dipole with a few outside attempts.

Will the Inverted dipole need a 1:1 balun at the feed point?

[The Collector]

Make a Ham International "Big Mac" copy...and make ME one while you're at it please

Good luck with your project

[The Collector]

I once made a Bazooka style twig using the bottom section of a silver rod. I fitted a 2ft approx thick wooden dowel down into it a couple of inches which was screwed in place and a piece of coax inner (with the clear plastic on it) attached to the screw with a washer. This was then wound up and up and then screwed into the wood at the top end. I then tightly wound insulating tape over the thing to waterproof it. I'd pre-swr'd the length of wire before winding it all up. It worked pretty well for a 6ft aerial but obviously not a well as it did as a proper silver rod.

I also made a ground plane for a silver rod that looked like a square version of the Sigma 4's crows nest, out of one of those 4-legged ground plane kits that you could buy back in the day. I added cross pieces between the legs for support towards the ends. It didn't make any difference at all lol, but it looked great!

The things we do when we're 14 or 15 eh

[porky.69]

Make a Ham International "Big Mac" copy...and make ME one while you're at it please

Good luck with your project

one of the best antennas back in the day

[JLow75]

Thanks all. Work is well in progress & should have 1st attempt up tomorrow. will post results/pics
Its great what you can do with 3M lengths of very cheap PVC waste pipe/overflow pipe

[mastercare]

Hi Jlow75
Last summer i built which is basically a Halo antenna for 10 metre band, it works very well and ive had some good DX on it subject to band being open which isn't very often at mo, its basically a square frame and on the net its known as homebase 10, its a folded dipole also i find it picks up very little noise. for 11 metres just make the dipoles a bit longer and tune it to the main part band u wanna use...
cheers
paul

[JLow75]

Not interested in DX / skip - I want an antenna that performs the best for local stations (up to about 20 miles away)

Yes I can try a halo too