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1-10 of 21 messages
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Roomcap HB9ABX
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by 5P1CC on February 4, 2009
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Hello... i would like to ask if anybody owns or operates an antenna called RoomCap by HB9ABX...?
Ther seem to be no information about it in the web, except for things published by HB9ABX himself..
So is anybody out there using this antenna..?
73 de Claus
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RE: Roomcap HB9ABX
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by N3OX on February 4, 2009
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If I told you, HB9ABX would come and kill me.
Let's put it this way.
It's a magic antenna.
Perfect design.
Better than any antenna out there.
Yet HB9ABX sells the plans one by one with strict confidentiality agreements to individual hams who find him on the internet.
One might wonder why he has no lucrative contract with some government or military organization to supply RoomCap antennas for their HF needs.
Honestly, even if he were on to some new antenna physics (which he's not), I wouldn't send him my dollars. His attitude is anti-scientific and unhelpful to the ham community, and if he were really onto something he could make money from it some other way.
If you want a good, short antenna for your car or home, build a conventional short monopole antenna with a large capacitance hat and good, high Q loading coils.
It'll get you "57 reports from Belgium on 160m" too, and you won't be supporting this "pay for plans and not tell anyone how much the antenna sucks" nonsense.
73
Dan
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RE: Roomcap HB9ABX
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by N3OX on February 4, 2009
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For those not familiar with HB9ABX, here are the conditions under which you may know how to build his antenna, from his website:
"The construction guide for the RoomCap antenna can be ordered according the following conditions.
Conditions:
Each one who wants the construction guide has to sign a NDA (Non Disclosure Agreement), and has to
make a contribution to the expenses of this project.
This contribution is: 100.- Swiss Francs, (or 65 Euros, or 100 US$), payable as written above.
No further charges apply."
So you see, 5P1CC, I couldn't tell you anything even if I had spent the money on the plans.
73
Dan
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RE: Roomcap HB9ABX
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by 5P1CC on February 5, 2009
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Hi Dan... yes i read a lot of that on his homepage and other places as well, and then i mailed him and asked, in a very polite way, why he didnt go public with this information on his webpage so this antenna could proof itself... but that only resultet in a new mail where he send me his "terms of purcase" and what else, meaning that if i wanted to know something i had to pay the 100eu, and forever keep silence about the holy grail of antennasecrets and magic fizz-bang...:-)
But im not going to pay one single penny for something i havent seen what is. Antennas or what else...
And im not going into his game, whatever that is, so i thougt that there might be another REAL user out there that dared to tell if this antenna works as well as he claims...
There is more than enough fruitcake-contraptions been hyped and sold as antennas, and im not going to spend anything on that either...:-)
So i suppose your suggestion could be the right one for me..:-)
Tnx for the answer..:-)
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RE: Roomcap HB9ABX
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by 5P1CC on February 7, 2009
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Well... i did some tinkering myself, and i believe i managed to make a copy of the roomcap myself.
Its just an ugly coil-wire-crocdileclip contraption standing here on my desk.
I can get a low swr on 40-30-20 m so far.
It receives signals ...
On 20 and 30m it receives strong signals...!
On 20 meters i just made contact with RK3QWW with only 2 watts.....!
Maybe its a bit to early to name this contraption RoomCrap....:-)
Sorry.. couldt help it.. had to write it.. apologize..:-)
So next is to make a copy of it OUTside in my garden, and compare it to my loaded dipole up 30 ft...
Ehm.... the secret...? There is no secret in my contraption..:-)
73 de Claus
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RE: Roomcap HB9ABX
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by N3OX on February 7, 2009
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"Ehm.... the secret...? There is no secret in my contraption..:-) "
Too bad, I was about to write a 60 EUR check and mail it to you.
Oh well.
:-)
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RE: Roomcap HB9ABX
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by 5P1CC on February 8, 2009
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Well... you could have it for free if there was...:-)
In fact i made 2 other contacts yesterday on 30 an 40 m... a bit of a surprise to me, maybe condx were up..
And maybe i could do the same with any meager piece of wire plugged into my tuner...:-)
Compared to my doublet, the doublet wins every time by far, much stronger sigs and less noise..
I hope i can collect the bits i need to make weatherproof this week, and then i will rise it in the garden..:-)
73 de Claus
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RE: Roomcap HB9ABX
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by N3OX on February 8, 2009
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Claus,
Ham radio is fun with horrible antennas. No doubt.
Piece of wire with your tuner, whatever.
It's pretty easy to make a piece of junk with gain of -10dBi as long as it's not 0.05wl long or less.
It's pretty hard to make a reasonable sized piece of junk have a gain of -30dBi. You do need to make it ridiculously short.
So there's a whole range of random antennas that will allow 1W to 10W output power with 100W applied.
A QRP enthusiast who runs 1W to good antennas makes tons of fun contacts every day... so, why not 100W to a terrible antenna?
The difference, of course, is that the actual QRPer may be able to turn the "power" knob up 20dB or 30dB with an amp if they need it ;-)
I tried an experiment with my near-half-wave tall vertical on 40m. Instead of using my proper matching network at the base, I switched it to the 80m position, just straight through coax connection to the base of a half wave wire. This is a terrible antenna setup, and I measured about 10dB loss on receive comparing the shack tuner + coax feed vs. the L network at the base.
So I use this bad antenna system and make a few contacts on 40m; I had a QSO with I1YRL who heard me perfectly and gave me a 579 report, I worked ZC4LI who was a new one for me on 40, and I busted a pileup on C57R, and all of this was in a short time.
The moral, of course, is that you have to be very critical of an antenna design to know whether or not it's radiating 98W or 9.8W, because either one will make contacts pretty easily ;-)
"Compared to my doublet, the doublet wins every time by far, much stronger sigs and less noise.. "
And that's the comparison many people with poor antennas don't do!
Now, to be fair to HB9ABX, his website does have many comparisons against other antennas, but I remain skeptical given that I'd have to pay $100 to attempt to reproduce his results, and I wouldn't be allowed to publish the full report of such a test.
73
Dan
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RE: Roomcap HB9ABX
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by 5P1CC on February 8, 2009
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Hi Dan.. youre absolutely right..:-)
It really takes a lot to know what you are doing, when you are comparing antennas..:-)
I did make alle the 3 contacts with my "contraption" standing here on the desk and with 2 w only, the needle was barely moving.. i have done that on my ladderline feeder as well not knowing the antennawires had broken of sometime...:-)
If the results HB9ABX are publishing is genuine he is really on to something, but i havent seen any results at all anywhere that wasnt published or relayed by him, so why arent there any other users flooding the net with fantastic reports....?
I wouldnt pay a dime for anything i havent seen or know what is, there are plenty of "contraptions" out there that wont do anything but waste your money...
Earlier this afternoon i made a scalemodel for 144 mhz and it does something... our local beacon (OZ7IGY) is not audible here on my ordinary outdoor antenna (VHF/UHF) but i can hear it loud and clear on the "contraption" on my desk... that doesnt prove anything but i think its remarkable, of cause its a matter of reflections and stuff as well, but the "antenna" is just a piece of wire 12" or so and a coil and a piece of pcb..:-)
If you are interested i will mail a picture of it, it might be a great addition to you "N3OX" callsign antenna..:-) I really liked that, and maybe "5P1CC" will make 12bd gain over a dipole, if so i could charge peoble money for using it as well..HI :-)
I hope and wish HB9ABX is on to something, but i want to see it to believe it..
73 de claus
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RE: Roomcap HB9ABX
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by N3OX on February 8, 2009
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I'd like to see your antenna... my email in my profile is good.
"I really liked that, and maybe "5P1CC" will make 12bd gain over a dipole, if so i could charge peoble money for using it as well..HI :-) "
It absolutely will give you 12dBd.
In the WPX contests.
;-)
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