Antenna Direct Radio Range

I had a few questions about the range you can expect from different antennas and which ones are best in terms of range, everything else being equal, which I hope you can help with. Forgive me if any of my questions are dumb because I am quite new to all this.

I haven't been able to find too much on the internet with regard to the range of different types of antennas just the odd page.

Dipole Antenna Range?

For direct radio range can you tell me roughly what range you could expect from a dipole antenna at the following wavelengths on all different modes at around 28 Mhz and at different power output in watts e.g. 5, 10, 20, 50, 100, 200, and so on and in different modes like FM, AM, USB? This is for direct radio range only.

1/4
1/2
5/8
0.64
1/1

Range of Yagi and Magnetic Loop Antenna?

I also wondered what range you could expect from different Yagi antennas mounted vertically with different numbers of elements? What effect do more elements have? Is it similar to the length of dipoles? I am guessing that more is better. I also wonder the same for magnetic loop antennas for range and the length of the wiring in the loop? How much do these two types of antenna improve on the dipole antennas, at least in one direction? 

Log Periodic and Delta Loops?

Are Log Periodic and Delta Loop antennas similar to Yagi and Magnetic Loop antennas? How does their range compare? Delta loops I read are meant to perform better at ground level than other antennas though I have no idea about range. And those Log Periodic antennas look like evergreen trees.

Back onto dipoles, the one thing that has been bugging me is would it be better to have a 5/8 dipole that goes from the ground up to the bottom of the roof of your house or to have a smaller 1/4 ground plane boomerang higher up for example on the chimney? 

The place I live in is a huge old victorian style house and I imagine the highest point which would be one of the chimneys must be 50 feet up. There are other buildings fairly close as well as big trees. And apart from the last 12 months, I live in an area that usually gets a lot of air traffic.

Final question, does anyone make a 0.64 dipole? These are slightly bigger than the 5/8 dipoles and I believe have a better range. Although I don't know what that range is. In terms of fractions of a wavelength, if my thinking is correct a 0.64 is 41/64ths whereas a 5/8 is 40/64ths of a wavelength so it probably adds just shy of 2 foot to the length if my maths is right.

If you're able to help give me a better idea on ranges especially for FM I would appreciate it for different types of antennas compared to dipoles and also whether a small boomerang high up is better or worse than a 1/2 or 5/8 dipole from the ground.

It depends entirely on the height of the antennas at both ends above sea level and if there's anything blocking that line of sight.

Whether it's a 1/4 wave or whatever doesn't matter, your local background noise floor, what your S meter shows on an empty channel, will be the limiting factor. In regards to modes CW is the one that'll eak out the absolute maximum range watt for watt, the rest are pretty much a crap shoot with the exception of SSB on a legal radio which will give you an extra S point due to the higher power output on an unmodified radio.

If you are at a low height and wanting to contact someone withina few miles at a higher elevation of a few hundred feet or more then the 1/4 wave will be the better antenna as it radiates a stronger signal at higher take off angles than the others.

For local contacts antenna height above ground matters more than what wavelength it is.

Dipoles are 1/2 wave. Anything longer than that and you start to have all kinds of funkiness happening with lobes and nulls.

Northern Crusader has said it well. There can be so many variables to consider.

A couple of unscientific sounding statements often heard regarding antennas, of which do contradict some antenna theory but are generally true for 27/28MHz are "as big as you can, as high as you can" and "height is might". Get an antenna up in the clear and it almost certainly will do better for line of sight than lower down.

A couple of great sources of info which will help answer some of your questions if you want to look them up are:

Old School: "The Radio Amateur Antenna Handbook" Read it as a young child and still have a flick through it from time to time. Describes many antenna types and has diagrams giving gain levels of various antennas compared to the basic dipole.

New School: Look up DX Commander Callum on youtube. I think he's a member here too. He has some interesting vids regarding radiating patterns and take off angles of different length antennas.

A practical example.. I tried a T2LT (which is effectively a ½ wave dipole) in my back garden surrounded by houses about 400' above sea level. I had continuous 5 to 6 signal of background electrical noise. The furthest line of sight QSO using about 20W on SSB was in the next town about 15 miles away.

I took that same setup to an open disused airfield a few miles from home which is about 820’ above sea level. The background noise dropped to between 0 and 1 s point, and I had many QSOs over 50 miles and one ear strainer was pretty much dot on 100 miles.

Height is might , thats true enough and having the antenna up and in the clear is the way to go.
Of the modes you are might most likely to be using (SSB,FM,AM ) SSB will give you a better chance for longer range contacts  but its not a power thing (4w constant to 12w pep), its all to to with the SNR signal to noise ratio. The 1/4w has a higher take of angle is always a funny one to hear ( or read) at what angles and at what heights are the tip heights of the comparison antennas ? It would be very easy to install a 3/4w-5/8 wave etc with much higher gain at certain high angles over a 1/4w. A dipole is 1/2 a wavelength ( 1/4 each side) because its impedance is close to the 50 Ohm output of a radio , around 72Ohm depending on height. Besides the "height is might"saying another one is "if you cant hear them you cant work them "( or even know they are there) Achieving a low background noise could be far more important than the actual antenna used.

Here is a take off angle and gain graph someone did on another website I'm on which compares all kinds of commercial CB antennas including some very famous ones people swear by - Antron A99, Imax 2000, Gainmaster, Predator, Starduster, J Poles and a few others. You'll see at most the difference between best and worst is about 3dB at low angles which is worth a single S point on a CB S-meter. 

Thanks for the information guys.  In my original post, I said Dipole when what I actually meant was vertical. 

To clarify I was essentially wanting to know whether a small boomerang on the chimney 50ft up would be better than a vertical from ground level going up to 20 or 30ft.

And the main thing I was interested in knowing was the direct radio range on FM with different power settings of verticals to Yagis, Magnetic loops etc all other things being equal. How far can you get out if you can manage to keep background noise to a minimum where you live?

I am already in an area that is reasonably high up so I wouldn't really be concerned with going higher only targetting urban areas that are lower down close by and also much further away.

Hi John,

There has been some invaluable information provided by our more knowledgeable Charlie Tango members already.

The study of antennas and indeed antenna propagation is a complicated subject with many facets, some individuals having devoted their entire lives to such understanding.

When we delve into the actual specifics of such subjects we often find that it is far more complicated than first imagined especially with many variables to add to our own specific needs or requirements. As such, a lot of individuals learn the broader aspects of antenna theory and can happily put them into practice.

Even if the broader aspects of antenna theory are utilised we can still be caught out by our own circumstances. 
The so called 'best antenna in the world' will prove fruitless if we live near a massive interference source, run poor feedline, have a poor performing transceiver or even indeed live in a proverbial 'radio hole' surrounded by high terrain.


Conor, (Northern Crusader), has given you some great insight and even a very useful graphical representation showing that when all things are equal there is very little to choose with the usual commercial antennas available.

Kevin, (Bean), has also usefully mentioned SNR signal to noise ratio as well as the utilisation of other transmission modes to improve antenna coverage. With his example in mind FM voice modulation actually reduces our possible antenna coverage.

Neal, (SangueG), has provided some useful resources and insight into his own antenna experimentation.


In answer to one of your specific enquiries, a 'boomerang' antenna is at best a poor compromise antenna. It is usually a 1/4 wave helically wound, (so already deficient), antenna masquerading as a poor dipole or 1/4 wave GP, (ground plane), and I am sure other antennas would outperform it regardless of how high you are able to get it mounted.

You other enquiries are pretty diverse which may require you to do some more research into particular fields. The internet is awash with valuable information on such broad subjects.


If it helps any there is a useful resource available online for antenna range predictions. You can enter specifics including your chosen location to provide mapping models for your enquiries remembering that these are an 'at best' prediction.
The link is below :-

https://www.ve2dbe.com/rmonline_s.asp


For help in utilising such a tool someone has helpfully provided a video tutorial online available at the following link :-

https://www.youtube.com/watch?v=WJPPUk37jUA



I wish you the best with your antenna research. 

I also would like to thank all the invaluable Charlie Tango members here that gave their time and knowledge freely in assisting you with your task.


All the best,
Victor