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Please don't laugh. I am totally ignorant about amateur radio. When I tried to use the internet to answer questions, all I have found are formulas and charts I don't understand. For example; I looked for instructions for erecting an inverted L antenna. I really needed to know how mush of the wire is used for the horizontal portion and how much for the vertical portion. I was hoping for percentages (60/40 or 70/30 etc.), instead all I have found is a formula.

I have purchased a Palstar R30A receiver and want the best possible reception. I was advised to use a 160/6 inverted L antenna with balum, so I purchased one. Now that I have it, the wire is much too long for my location.

Did I receive bad advice? I didn't know what questions to ask. What are my options? By the way, what does 160/6 represent?

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First, I believe the 160/6 might refer to the antenna's coverage of the 160 meter band through the 6 meter band, with all other ham bands between included. Only important if you plan to transmit.

If you're only interested in short wave listening, it simplifies the antenna requirement. My suggestion is to string up whatever length of wire you have. More is better but don't stress over a premade antenna not fitting your lot. Simply cut to size.

The balun can be optional for simply receiving. In fact, I would connect with the balun and then later bypass the balun just to compare. Part of the fun of experimenting! Have fun and discover what works.

Hope this helps.

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    $\begingroup$ "cut wire to length" I would advice not to cut your purchased antenna, just use any lenght of random wire for your RX antenna. You purchased antenna may be of use to you later, or you can sell it.... once you cut that one, you cannot use it later, nor sell it. $\endgroup$ Feb 6, 2018 at 8:25
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Where are you using the radio ? In the City... In the countryside ?

The City will be much noiser (from an RF standpoint).

If you are heaving "solid noise" everywhere that you tune too - you may have some local RFI (Radio Frequency Interference) due to your computers, Tv, Strip Tube lights, A/C etc.... The easiest way to fund this out is

a) Get your radio running on a car battery (12V) b) Turn all the electricity off in your house/flat !!!

If things improve drastically you are causing the issue.

If things stay the same ... it is something outside your house.

If the issue is outside your house - disconnect your very large antenna, and replace with a simple vertical - as in a piece of wire (obviously take care due to power lines etc) plugged into to your receive socket.

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I'm sorry that I didn't see your question earlier. As @AlmostDone says, "160/6" means that the antenna is designed to work from the 160m band to the 6m band, in other words 1.8 MHz to 54 Mhz.

How much of your antenna should be horizontal and how much should be vertical is not very important, but you'll want the antenna to be as high as you can practically accomplish, because the higher it is the better you will receive far-away shortwave stations. If the wire is too long for your property, then a good solution could be to weave it back and forth a bit, or bend it so that it wraps around your property. (Gentle bends, such as 60° or less, would be better than sharper bends.) The horizontal part of the antenna won't do much for receiving shortwave broadcasts, but do help make the impedance of the antenna more convenient for the receiver.

If you have to cut the wire, it will change the impedance of the antenna and make it difficult to sell as @EdwinvanMierlo says. For receiving, the impedance of the antenna often doesn't matter very much, but for transmitting it does matter; so I'd recommend not cutting the wire if you might try to resell the antenna later, or if you are thinking about getting an amateur radio license and transmitting with the antenna later. If you have to cut it, try to cut off as little as possible; if you have to lop off more than about a third, then the impedance of the antenna might become a problem for the receiver at the lower frequencies.

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It is first important to know what frequency you will be using. The higher the frequency, the shorter the antenna and vice versa.

A basic formula for a dipole antenna (not an L antenna) would be to divide your operating frequency in MHz (e.g. 15 Mhz) into 468. That will give you the length of your antenna in feet (e.g. 31.2 feet). From this, you can make a dipole antenna = ----------x----------- or an inverted vee antenna (Google 'dipole antenna','inverted vee antenna' or 'how to construct a half wave HF dipole antenna').

Be advised that the dipole and inverted vee antennas are directional. So depending on where you live and with whom you wish to communicate, you will ideally want to align your antenna broadside to that direction.

A vertical or discone antenna will allow you to transmit and receive in a 360 degree pattern.

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