TheRadioBoard

Hello Friends ,
My antenna is an inverted L antenna. The long wire antenna is built V-shaped. This is one leg of the "V" 30 m long stretched between a tree and a 6m high mast. Another wire is with a 15m long.
Roof of the house of the shorter leg. Together, therefore, a 45m long long wire antenna.
I would like to increase my Antennamast on 10m, but am not sure whether the shape of the antenna is optimum.
Question for you: is this form of antenna unfavorable? Another form of the antenna can unfortunately not my property. I ask for your opinion.

Johannes
excuse my awful english

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Please visit my website at: http://schwitt.de/radiobasteln

Johannes

I have a similar aerial although it doesn't extend all along the side of the house like yours. I have no technical data but it works well for me. I can get Voice of Croatia, Radio Tirana and the 2000KW (!) Hungarian station.

BTW the graphics on your website are great. I love the animated DXing ones. Is there a way of copying them for private use? I'd love to have one on my desktop.

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John

Hi John,
you can get the animated graphic to your needs. point with the mouse on the graphics and copy with left mouse button and save it on your computer.

I make the animated graphics wit FLASH and transform it in gif.

I want to make the Antenna higher and hope it will bring more stations.

Johannes

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Please visit my website at: http://schwitt.de/radiobasteln

Johannes,

Assuming we are talking about operation on the AM BCB only, the shape and size are not "Optimum".

That does not mean "unfavorable" though.

Since almost none of us can erect an "optimum" antenna for that band, reception can be unpredictable.

So, the best we can do in theory is to make the antenna as high, as long, and in the clear as we can.

Also use a good ground(An ifinitely long silver sheet under the antenna).

With DX reception being unpredictable, depending on conditions at your location, you will just have to try different configurations and see what works best for you!

73
de kb0lxy

Hello Johannes,

I concur with Ham-er's comments about having a good ground. It is just as
important as a good antenna. Another "must have" accessory is an
antenna matching unit. I favour the series tuned variety.

Cheers, J.B., VE3EAR

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To be where I am, I had to leave where I was!

Hello radiofriends,

every modern house in Germany, located around the building a loop of metal in the earth. Furthermore, all water pipes and gas pipes are made of metal together. The protective earth of the power line are also connected to this. This all gives a very good ground connection for radios.
Only the V-shape of my antenna does worry me.

J.B.
what do you mean by "antenna matching unit" ? A ATT or a Balun ?
Here my ATT :


Johannes

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Please visit my website at: http://schwitt.de/radiobasteln

Hi Johannes,

Your A T T looks great! What does the second T in yours stand for?
Antenna Tuning T...? They have a number of names, some of which
are not correct, but they all do the same job. The matching of the
antenna to the radio so that the transfer of energy is maximized.
I wouldn't be too concerned about your antenna arrangement.

73, J.B., VE3EAR

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To be where I am, I had to leave where I was!

[quote="Johannes"]Hello radiofriends,

every modern house in Germany, located around the building a loop of metal in the earth. Furthermore, all water pipes and gas pipes are made of metal together. The protective earth of the power line are also connected to this. This all gives a very good ground connection for radios.
Only the V-shape of my antenna does worry me.

Johannes

That's very interesting and a very good way for grounding.

In my job I build cable tv 'headends' and we do the same thing. Boss says to tie the loop to 8 foot earth rods every 5-6 feet. Sometimes we installers are lazy and those rods become 10 feet apart

My antenna shape is very similar to yours. I'm very pleased with it.

-Bill

Hi J.B.,
ATT is the German abbreviation for "Antennentuner".
In the future i will use AT.
The AT on Dave's website was my model. It works wery well.
In my job i work too with high tension (10-100.000 Volts). I work for an distributor for gas, water and electric. A wrong click on the computermouse and ouer city is dark.

Exray,
I have visit your "sparkbench". It is a wonderful site with great projects. I love the old look and the old big knobs of your homebrew radios.
Now i have found the picture of your antenna in an older posting.

Johannes

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Please visit my website at: http://schwitt.de/radiobasteln

I think this model of the antenna would be really helpful for getting a good & clear signals. I would also like to sry this experiment on my tv antenna. I hope it would work. Let's see...

Spam links removed by moderator

Johannes' site - English translation.
http://translate.google.com/translate?s ... basteln%2F

.......................

I use a very similar antenna with no problems , and when they used SSB radios on comerical Vessels on the inland water way a good portion of the inverted L antennas were Ved back

My ant is 90 ft long and the slanted back portion is 30 ft , dropping back and below the horizontal part

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Mark

Hello Members,

I determined that Criswat is a spammer. He posted a spam link. In checking
the IP address of his post, it was found to be in India. His IP was also one
listed as a spam IP location.

I have taken measures to cancel his account. I also banned not only his IP
address but all in the range of his ISP. His spamming says on The RadioBoard
are now over.

This person was smart in how he worked his post to blend in and at the
same time offering his spam. But I am one of the few forum owners that
check every member as well as every post and every link.

I now return this thread to it's normal schedule.

Dave

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Please visit my website at: http://www.makearadio.com

Attaboy, Dave, thanks for your eternal vigilance, and everything else about this board.

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God made us able to listen to one thing while doing another, so radio is a divine gift.

My first antennas were inverted "L" types. I have used them for transmitting (shhhh!) and receiving on the mediumwave band.
They tend to have the most vertical (groundwave) gain opposite of the horizontal portion of the wire.
So for example if you put up an inverted L with the horizontal part stretched east you will get more gain from the west.
However this is mostly only useful for groundwave daytime work, since at night that horizontal part will catch more skywave skip.

The antenna I favor more over the usual inverted L is the single wire Windom antenna.
This is setup much like like an L, but the vertical part of the wire is off towards the center.
So it's literally the inbetween version of an inverted L antenna and a T type antenna.

So what's the difference where you connect that vertical wire to the horizontal part up in the air?
Simple... sort of..
With an inverted L you get more gain towards one side of the antenna for daytime groundwave reception, and gain for skywave broadside of the horizontal part during night.
With a T areal where you connect the vertical wire directly between the (tophat) stretched top wire you get great daytime groundwave reception but it's not so useful for nighttime skywave.
So in between is the best of both worlds which is why the Windom was very popular in the 1930s for AM broadcast band reception.

Horizontal antennas are great for picking up skywave nighttime skip, vertical is great for daytime groundwave. So combine the two (the Windom) and voila!

Sorry if off topic but I felt the need to post this

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