I have two 3.5" by 48" heavy shipping tubes that are just SCREAMING to be coil forms.I'm thinking remote tuner, and maybe switchable taps as well.
Your experiment makes we want to go that route, instead of the HF2V that was practically given to me for under $50.
Lot here is 60 x 100, long axis runs E-W :( But I can use my neighbors trees... she gave me permission.
She's not there anymore, bad interior fire, not enough insurance... abandoned house now.
"Where would we be without the agitators of the world to attach the electrodes
of knowledge to the nipples of ignorance?" ~ Professor "Dick" Soloman
You have more space as me ..... my plot is 100 feet by 25 feet, that's all...
The helical is a oneband antenna, just now in qso with G7KLJ, he runs only 30 watts and the helical puts in a 3 dB better signal as the inverted L.
I use the streetlantern in the front yard to string a few lines to ;)
Will make a few pictures to show the setup.
Your idea sounds good, though i don't like coils in antenna's to lengthen them, too lossy, even top loading coils, i'd rather use tophats or top wires to load up the antenna's.
take care,
Cor
"If the Republicans will stop telling lies about the Democrats, we will stop
telling the truth about them." - Adlai Stevenson (1900-1965)
“I’m not liberal/conservative, I’m anti-idiotarian.”
At some point in the last 20 years, the left moved to the center, and the right moved into a mental institution
Yea, I need to put up a big "T Marconi" and see how low it loads up. And get better with EZNEC.
If the lot was rotated 90 degrees, I'd try a reversible wire Moxon on 75/80.
"Where would we be without the agitators of the world to attach the electrodes
of knowledge to the nipples of ignorance?" ~ Professor "Dick" Soloman
got piccie:
Last edited by PA5COR; 06-15-2010 at 06:25 PM.
"If the Republicans will stop telling lies about the Democrats, we will stop
telling the truth about them." - Adlai Stevenson (1900-1965)
“I’m not liberal/conservative, I’m anti-idiotarian.”
At some point in the last 20 years, the left moved to the center, and the right moved into a mental institution
So, what kind of roof mulch do you use to grow metal RF flowers like that?
BTW, your signature line is elitist. ;)
"Where would we be without the agitators of the world to attach the electrodes
of knowledge to the nipples of ignorance?" ~ Professor "Dick" Soloman
;)
The large vertical in the piccie in the middle starts at the groundlevel, 50 feet up, you can't see the 2 top hat wires clearly but they are there.
Doing some calculations and the efficiency of the vertical is 78% more or less compared to a full size vertical for 160 meters.
You caan make out the 5 element 6 meter beam, the 11 element 2 meter flexa yagi and the 23 element flexa 70 cm yagi.
The Diamond x 510 is above that.
On the left is the reworked Imax 2000 with 5 meter radials i was given, it now works fine on 10/12/15/17 as vertical.
The OCF ( Fritzel FD-4) with coil and wire for 160 is barely visible.
Time for a radio day, then back to the working table for a magloop for 160.
Who said you can't make a reasonable antenna for 160 meters on a small plot?
:chin::)
"If the Republicans will stop telling lies about the Democrats, we will stop
telling the truth about them." - Adlai Stevenson (1900-1965)
“I’m not liberal/conservative, I’m anti-idiotarian.”
At some point in the last 20 years, the left moved to the center, and the right moved into a mental institution
Great work Cor....You now have to work me between November and March next year....Looking forward to the S9+++ signal report on Topband...
Bob..VK3ZL..
Excellent job, Cor. Any antenna is better than none; that it compares favorably to a full-size radiator is the proverbial icing on the cake.
73 de Mike, N5RLR
* * * * * * * * * * *
"I drink for the honorable purpose of getting bagged." -- Jackie Gleason
"It is my belief...that the truth is generally preferable to lies." -- Albus Dumbledore
Thanks for all the nice words ;)
Except for the OCF antenna with coil and piece of wire made fit to work at 160 up, the vertical antenna was the only choice for DX, or a chance of DX.
The city lot i live on is just 100 feet long, 25 wide...
Room enough to go up, and the helical was tried first, going from the principle that winding a 1/2 wave length of wire will raise the radiation resistance, and improve radiation resistance and efficiency.
It worked fine, but with only the OCF antenna to compare it and a few friends with T and L antenna's i decided to test these too.
Off the helix coil went and i put up T and full size L antennas 15 meters ( 50 feet) vertical.
The results were not bad, but looking back over the months use of the helical vertical, something was missing, these L and T antenna's weren't as good as the helical.
So, this week i lowered the mast, and restored the helically wound antenna, with 2 x 6 meter long wires on top for top hat capacity.
The earth radials stayed the same for all antenna's so my personal experience is that this antenna works better local and DX as a L or T antenna with the same hight.
I even tried a 3/8 L antenna to get the current higher up the wire...and less loss in the radial net.
Tests over the last winter till now with UK stations 400 - 1000 km away confirmed the results, each antenna was up at least a month for testing to get some realistic results.
G7KLJ Steve, was a big help in this providing many reports and listening to my ramblings on antenna's.
(Some help from the book Low band DXing from ON4UN, Rothammel, RSGB/ARRL antenna boooks, and personal experience too)
All tests were done with standard 100 watt, the SB-1000 was not used.
Simply said the antenna is made of 9 glass fiber sections of 4 feet length each 1 1/2 inch thickness used in the army for putting up camo nets.
Total length 10.80 meters on which 100 meters of aluminium wire is wound ( always wind some more on it for pruning it to get it resonant)
That wire is sold in several thickness in agricultural outlets for fencing wire, i chose the 2.75 mm wire just over 0.1 inch thickness.
On top of that i made an topsection of 4.20 meters with 20 mm aluminium tubing and the last part a glass fiber top.
The top section has a simple wire running straight up that section to the top, where 2 wires of each 6 meters are connected as top capacity hat.
An elaborate ( 400 meters) of copper wire went in the ground filling every nook and cranny of the 100 x 25 feet city lot, several 40 meter long wires over the fence, and to the front of the house.
The ground net of the house was connected even the kitchen sink ( stainless steel) is connected to that.
Living on good conducting ground, young sea clay, i get decent results, even living on the edge of the town.
Feeding it directly with 50 Ohm coax, a few clamp on ferrite's at the feed point around the coax to keep RF from the outside of the coax.
Pruning it with the MFj analizer at the feedpoint, taking off windings to get it resonant in the part of choice for you at 160 meters.
Bandwith here between 1:2 is around 100 KHz.
Since we only can operate from 1810 to 1880 that is wide enough for the whole band.
Tried the Sb - 1000 on it, and it works fine with full power in it.
No televisions or other consumer goods were disturbed or hurt by that
If you read the thread from the start you get the idea how to go with it, if you want to build one, or just ask and i'll try to answer your Q's.
73,
Cor
Off to make a magnetic loop for 160....
Ehhh Bob, i would be happy with a 5 by 2.....;)
All typo's are mine alone...
Last edited by PA5COR; 06-17-2010 at 03:38 AM.
"If the Republicans will stop telling lies about the Democrats, we will stop
telling the truth about them." - Adlai Stevenson (1900-1965)
“I’m not liberal/conservative, I’m anti-idiotarian.”
At some point in the last 20 years, the left moved to the center, and the right moved into a mental institution
Done.
Test loop ready and made some qso's with iit on 160.
Just 50 watts before the variable C started to arc...
9 feet diameter, will post piccie later and more results.
Last edited by PA5COR; 06-17-2010 at 11:08 AM.
"If the Republicans will stop telling lies about the Democrats, we will stop
telling the truth about them." - Adlai Stevenson (1900-1965)
“I’m not liberal/conservative, I’m anti-idiotarian.”
At some point in the last 20 years, the left moved to the center, and the right moved into a mental institution
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