Guy--
Thanks-- beautifully described. It is as I thought, but the diagram on the
W0UCE page confused me, particularly with the connections to the
Counterpoise.
Bill--W4BSG
----- Original Message -----
From: "Guy Olinger K2AV" <olinger@bellsouth.net>
To: "Bill Aycock" <billaycock@centurytel.net>
Cc: <topband@contesting.com>
Sent: Thursday, December 08, 2011 1:56 AM
Subject: Re: Topband: Best small space antennas
> Bill,
>
> Instructions for creating a drawing of the basic configuration: 160 only,
> no tuning inductors or capacitors. Tuning after construction by adjusting
> the length of the top of the L.
>
> Start in the center of a blank piece of paper. Draw a transformer with a
> completely separate primary and secondary. Draw the core bars vertical so
> all of one winding is on the left and all of the other winding is on the
> right.
>
> On the left side of the tranformer connect the upper end of the winding to
> the inverted L.
>
> On the left side of the transformer connect the lower end of the winding
> to
> the folded counterpoise.
>
> On the right side of the transformer connect the upper end of the winding
> to the feed coax center conductor.
>
> On the right side of the transformer connect the lower end of the winding
> to the feed coax shield. Do not ground the coax shield until 30-50 feet
> away from the transformer.
>
> That's the wiring diagram.
>
> Length of the inverted L is adjusted to prune to resonance at your choice
> of center frequency. This appears to be centering in the vicinity of
> 130-140 feet, **IF** you are using an isolation transformer built to our
> specs, but we will know more when there are 100 of these up in the air and
> reporting.
>
> The transformer is wound on an Amidon T300A-2 #2 material powdered iron
> toroid. Twenty bifilar turns of #14 double polyimide insulated, sleeved
> with AWG12 teflon standard wall no shrink sleeving. Requires 15 feet of
> wire and 15 feet of teflon sleeve, cut in half to make the two winding
> wires.
>
> 73, Guy.
>
> On Wed, Dec 7, 2011 at 11:33 PM, Bill Aycock
> <billaycock@centurytel.net>wrote:
>
>> 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<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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