From one of the FB ham radio groups:
Anyone? Bueller?Your not dedicated till you drive a ground rod home thru the south texas clay. Today i set up my hf20a wire antenna. This antenna needs 2 ground rods. The good news is that i get 1:1 swr from 160-10m no tuner.
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1:1 SWR from 160m through 10m without a tuner? That's not an antenna he's using, it's a dummy load.
All the world’s a stage, but obviously the play is unrehearsed and everybody is ad-libbing his lines. Maybe that’s why it’s hard to tell if we’re living in a tragedy or a farce.
You got me,Originally Posted by KJ3N
maybe a picture of the installation might help.I looked the antenna up, looks like a OCF dipole terminated like a Beverage Antenna.
Him claimed "1:1" match is problematic in wording and most likely improbable in real life; maybe he misread or misspoke in his description
antenna.jpg
This was useful (not) in my understanding.
.
Da Pope is wise.
The only way you get those kind of results is with a lot of loss in the antenna system. Oh, you can get RF to radiate off of it, but the question is exactly how much of the total applied RF is getting radiated.
"People Who Don't Want Their Beliefs Laughed at Shouldn't Have Such Funny Beliefs" -AD5MB
"If someone tells you he believes in and talks to an invisible bunny named Harvey, you put him on medication and a regimen of therapy. If someone tells you he believes in and talks to God, well, that's perfectly acceptable. Why that's the case is impossible for me to fathom." - WP2XX
Latest ClubLog entries.
Whenever someone confuses RF ground with AC ground, Domo kills a kitten.
Now we have to perform a sacrifice to W4RNL to right the wrongs.
Jim
The machine does not isolate us from the great problems of nature but plunges us more deeply into them. - Antoine de Saint-Exupéry
I suggest a 200 watt incandescent bulb.
"Where would we be without the agitators of the world to attach the electrodes
of knowledge to the nipples of ignorance?" ~ Professor "Dick" Soloman
My homebrew OCF works from 160 - 10 but will not be 1:1 everywhere....15 meters is baaaaaad ;)
Though nowhere worse as 1:3 ( needs tuner) 160 - 80 - 40 - 20 -18 -12 -10 are moostly below 1:3 or even 1:1.2.
First thought this is not an OCF antenna but an end fed antenna with a short piece counter poise and earth connection, clearly from the provided piccie you see only the short end grounded, the longer wire has the "Special purpose part" in it.
Still a wire fed with 1:4 or 1:9 un un won't give you 1:1 on all bands.
Possibly with a ruddy large non inductive 50 Ohm resistor in it ;)
From their advertisement:
Package Contents:1× HF20A Balun(The white Box)1× Special-purpose part (The golden metal Box) Must be that 50 Ohm ruddy big resistor then ;)
http://www.aliexpress.com/item/HF20A...050744819.html
More piccies of the gold colored heatsinked "Special purpose part" LOL
Here they state SWR < 1 :2
Radiating wire 20 meters, short side 1.5 and after the "special purpose part" to ground also 1.5 meters.
So in effect a radiating dummy load.
Most power will be lost in the balun and resistor, though on some frequencies it might actually radiate a bit better as a leaky dummyload.
You know how things work, if anyone didn't had a decent antenna up and tries this as first one it is a very good antenna.....
Till he finds out what a real antenna does.
Last edited by PA5COR; 06-23-2015 at 04:10 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
Same reason I'm not a fan of the folded dipole. Resistive loads are futile.
"Where would we be without the agitators of the world to attach the electrodes
of knowledge to the nipples of ignorance?" ~ Professor "Dick" Soloman
I made a PSK-31 contact with a friend while he was testing his rig into a dummy load so, yeah, I agree—you can get some RF to radiate off of pretty much anything. That doesn't make it a good antenna, however.
Cor, I think you're right. That “Special Purpose Part” looks suspiciously like a high-wattage resistor, doesn't it? Check out this page!
Last edited by NQ6U; 06-26-2015 at 08:19 PM.
All the world’s a stage, but obviously the play is unrehearsed and everybody is ad-libbing his lines. Maybe that’s why it’s hard to tell if we’re living in a tragedy or a farce.
They make fairly good driven elements, though.
Jim
The machine does not isolate us from the great problems of nature but plunges us more deeply into them. - Antoine de Saint-Exupéry
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