Guy--(and others who may contribute)
I have been following your posts, and have some questions, brought on by a
view at the W0UCE diagrams, at:
http://www.w0uce.net/K2AVantennas.html
The top figure seems to match what I understood from your post, but the
figure that includes the Inv "L" confuses me, particularly with regard to
the connections. I need a more simplistic description, including the
connections to the transformer
Thanks- Bill--W4BSG
----- Original Message -----
From: "Guy Olinger K2AV" <olinger@bellsouth.net>
To: "Jim Miller Waco Texas WB5OXQ" <wb5oxq_1@grandecom.net>
Cc: <topband@contesting.com>
Sent: Wednesday, December 07, 2011 7:57 PM
Subject: Re: Topband: Best small space antennas
> Note: the following is not a theoretical or untested antenna. There
> are working antennas in the field using the folded counterpoise
> described below, scoring well in contests**, in use up to a year and
> more. Contest scores of the sort attained are not made using antennas
> with significant deficiencies or fundamental flaws.
>
> A miscellaneous end-fed inverted L or end-fed inverted U over an
> elevated 5/16 wave single wire folded counterpoise (FCP) will have
> good radiation from a small lot, with the ability to put out a strong
> signal not usually associated with small lots. In the simple
> implementation of this antenna (160 only), the length of the L or U is
> adjusted for zero reactance, usually resulting in a 50-60 ohm feed Z
> at resonance.
>
> There are NO radials. The main design point of the antenna is to
> minimize lossy currents induced in the dirt and confine TX signal
> current to the FCP and the radiating wire. This is a real, and lossy
> issue for a few short or miscellaneous radials. Enough of an issue to
> kill 15 dB.
>
> The radiating wire first goes up as much vertical as you can manage,
> then out as far as manageable, and then down if length is still needed
> to prune to resonance. The main point is to pick a feed point on the
> property that has your best vertical rise and then get the rest of the
> length for resonance however you can. For some properties this has
> meant putting extra angles in the up+over+down radiator. Some
> properties will not need the "down" part.
>
> The antenna uses a REQUIRED isolation transformer at the feed point
> because the counterpoise is NOT resonant, and the feed would really
> rather use the much lower Z but hugely lossy coax shield current as a
> counterpoise. The folds in the FCP are designed to maximally reduce
> counterpoise fields at the ground, reducing lossy currents in the
> dirt.
>
> The isolation transformer's leftover inductive reactance, a
> disadvantage in many applications, in this case helps to tune out the
> capacitive reactance of the FCP and reduces the length of the
> radiating wire needed to achieve simple resonance for the antenna.
>
> The counterpoise extends plus and minus 33 feet from the feed point,
> 167 feet folded into 66 linear feet occupied on the property. The
> middle 20 feet of the 66 should be straight, but either end can be
> bent away from the straight line to accommodate the property. Up 8
> feet or higher is recommended. Lowering the counterpoise increases
> the coupling to dirt, increasing losses.
>
> The isolation transformer uses the same physical components as a
> balun, but the unlike the balun there is NO connection of any kind
> between the primary and secondary windings. This is accomplished with
> twenty bifilar turns of double polyimide insulated #14 with teflon
> sleeving wound on an Amidon T300A-2 #2 material powdered iron toroid.
> One wire is the primary, and the other is the secondary. The low MU
> powdered iron toroid was picked over time to avoid heating, still
> provide required coupling, with other choices sometimes failing in
> spectacular fashion. We have no information of our currently-used
> winding method on the Amidon T300A-2 ever failing for any cause,
> though we would not expect it to survive a direct lightning strike.
>
> With the isolation transformer, the antenna and FCP is entirely above
> ground and not connected to anything else. We use a 5 megohm resistor,
> in parallel with a non-resistor lawn mower spark plug, from the FCP to
> ground as a static drain. The gap drains lightning induced voltage to
> protect the resistor, the resistor drains wind, snow, rain static.
> The resistor and gap protect the winding from a voltage puncture that
> will grow into a carbon track to ground.
>
> 73, Guy.
>
> ** As reported in Dec 2011 CQ, Jan 2011 CW160CW contest, USA low
> power unassisted, the 29 scores over 100K out of 335 scored logs in
> class:
>
> Station, state, score, QSO, ST+PROV, DX
>
> K9AY WI 259,346 991 58 36
> W0UO TX 250,716 882 58 44
> K1EP MA 232,750 909 56 39
> K2AV NC 223,908 907 57 37 << No radials, 5/16 FCP
> K8BL OH 203,328 819 58 38
>
> KU1CW KS 197,885 795 58 37
> N2WN TN 191,090 640 55 42
> WB8JUI OH 190,372 852 58 38
> N7IR AZ 183,855 856 58 27
> W2TZ NY 178,633 723 56 35
>
>
> NA8V MI 177,030 793 59 31
> W4AA FL 173,619 494 56 45
> K1HTV VA 172,956 733 55 32
> W1WBB RI 161,550 654 55 35
> KU8E GA 152,613 615 58 35
>
> W7RH AZ 135,369 500 55 34
> K4WI AL 128,520 509 55 30
> N9NCK WI 126,162 516 55 31
> KV8Q OH 125,741 674 57 20
> N9AUG OH 125,330 608 55 28
>
>
> W2TX FL 121,800 504 52 35
> K9QVB IL 120,120 641 56 21
> WW3S PA 119,848 706 55 16
> K2UF NY 119,392 541 53 29
> K0PK MN 118,400 678 58 16
>
> WF4U UT 114,239 664 56 15
> W1BYH MA 106,444 404 54 35
> W5WMU LA 106,020 574 54 22
> N4JF AL 101,920 493 54 26
>
> ** 3830 claimed scores listing of Dec 2011 ARRL 160 contest, North
> America low power unassisted, top 20 of 119 listed as of this writing:
>
> Station, state, score, QSO, ST/PROV, DX
> 2011 ARRL 160 - 3830 Claimed Scores 06Dec2011
>
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Call QSOs Sec Cntry hr Score Club
> NA Single Op LP
> K8FH 920 74 18 27 175,076 Medina 2 Meter Group
> NE9U 978 75 14 172,927 MWA
> K4FT 976 75 9 28 166,236 KCG
> WB8JUI 940 71 9 21.32 152,560
> K0TI 920 76 5 21 150,255 MWA
> K0DI 875 75 8 28 146,495 Lincoln ARC
> K2AV 788 65 9 21.5 119,066 PVRC << No
> radials, 5/16 FCP
> W0DLE 725 74 3 21 112,343 Grand Mesa
> K9MMS 653 74 10 16 112,224 SMC
> K0PK 657 72 6 19 104,130 MWA
>
> K3PA 618 74 7 101,817 Kansas City DX Club
> WA1FCN 645 68 7 99,864 ACG
> K2ZR 695 64 4 20.0 90,112 Western NY DX Associ
> K0AD 584 75 6 10 88,500 MWA
> W0UO 519 71 9 14 85,680 NTCC
> K0CN 478 73 11 83,076 MWA
> N1IX 516 60 10 13 78,540 YCCC
> VE3OSZ 442 68 15 77,854 CCO
> W9ZRX 492 69 8 20.5 77,616 SMC
> W7RH 437 72 8 76,869 Arizona Outlaws Cont
>
>
>
> On Sun, Dec 4, 2011 at 8:18 PM, Jim Miller Waco Texas WB5OXQ
> <wb5oxq_1@grandecom.net> wrote:
>> With limited space what is the best antenna for 160? The only room
>> available is a 130X50' area. Ground radials will be nearly impossable to
>> put in large enough to be of much value. 1/4 wave antenna tried, very
>> narrowband and interfeared with every receiving device in a block. I may
>> just be out of luck. wb5oxq
>> _______________________________________________
>> UR RST IS ... ... ..9 QSB QSB - hw? BK
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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