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5	CHARACTERISTICS OF ANTENNA
6	ANTENNA CHARACTERISTICS
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9	RADIATION RESISTANCE
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11	SOME COMMON METHODS OF LOADING
12	SOME COMMON METHODS OF LOADING
13	CONTINUOUS LOADING
14	4 AND 8 FOOT HELIX TABLE
15	4 AND 8 FOOT HELIX
16	CURRENT PROFILE 4 FOOT HELIX (D=18 INCHES)
17	CURRENT PROFILE 4 FOOT HELIX (D=66 INCHES)
18	CURRENT PROFILE 8 FOOT HELIX
19	IMPROVING CURRENT PROFILE ALONG THE LENGTH OF A HELIX
20	THIS ANTENNA WAS USED FOR 15 METER OPERATION WITH A POWER OF 5-10 WATTS. IT WAS GROUND MOUNTED AS SHOWN AND USED SHORT FOLDED RADIALS. MANY CONTACTS WERE MADE ALL OVER THE WORLD. THIS ANTENNA WAS DESTROYED “INTENTIONALLY” BY DRIVING WITH ENOUGH POWER TO SEE WHERE THE WEAKNESS IN THE DESIGN WAS LOCATED.
21	LEARNING FROM FAILURES THE FAILURE MECHANISN WAS OVERALL HEATING OF THE ANTENNA. THIS WAS FROM IxR LOSS DUE TO THE EXTREMELY SMALL SIZE OF THE WIRE USED TO CONSTRUCT THIS SCALE MODEL ANTENNA. THIS INDICATED THAT EVEN WITH LOW POWER (100 WATTS) A LARGE UNIFORM CURRENT WAS PRODUCED ALONG THE ENTIRE LENGTH OF THE ANTENNA. THIS INDICATED THAT IF YOU ARE GOING TO MAKE DLM ANTENNAS USING THIS DESIGN, THEY MUST BE CONSTRUCTED OF SUITABLE MATERIALS TO REDUCE I X R LOSSES TO A MINNIMUM
22	SOME PREVIOUS RESEARCH CONDUCTED ON HELIX ANTENNAS EXPLANINED SOME OF THE OPERATING PARAMETERS SEEN IN DLM ANTENNA OPERATION
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24	POWER DISSIPATION IN A DLM ANTENNA PHASE MEASUREMENTS MADE ON DLM ANTENNAS HAVE INDICATED A CONSTANT PHASE ALONG THE HELIX FROM THE TAP POINT TO THE TOP OF THE HELIX, MID-SECTION AND THROUGH THE LOAD COIL. THIS MEANS THAT THE HELIX AND THE LOAD COIL WILL NOT DISSIPATE ANY APPARENT POWER AND THE ONLY POWER DISSIPATED WILL BE I x R POWER OR JUST THE LOSS OF POWER CREATED FROM RESISTANCE OF THE LOAD COIL WINDING. (i. e. resistance of the wire) THERE IS NO I²R LOSSES IN A DLM FROM THE HELIX TAP POINT TO ABOVE THE LOAD COIL SEE OVERHEAD SLIDES
25	BASIC DLM ANTENNA A DISTRIBUTED LOADED MONOPOLE ANTENA IS MADE FROM FOUR BASIC PARTS. 1. HELIX 2. MID-SECTION 3. LOAD COIL 4. TOP-SECTION
26	"COMBINING A HELIX WITH" COMBINING A HELIX WITH A LOAD COIL PROVIDES UNITY CURRENT DISTRIBUTION ALONG THE HELIX AND EXTENDS TO THE TOP OF THE LOAD COIL IN ADDITION CONSTANT PHASE IS EXTENDED ALONG THE HELIX , THROUGH THE MID-SECTION AND ALSO THROUGH THE LOAD COIL THIS UNITY CURRENT DISTRIBUTION IS 2-3 TIMES LARGER THAT THAT OF A ¼ WAVE VERTICAL.
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29	REMOTE CURRENT PROFILE MEASUREMENTS CURRENT PROFILE MEASUREMENTS ALONG AN ANTENNA LENGTH ARE MADE WITHIN THE NEAR FIELD OF A GIVEN ANTENNA. THESE ARE RADIO FREQUENCY MAGNETIC FIELD MEASUREMENTS AND ARE MADE USING A TUNED COIL. THE SENSOR IS THEREFORE A TUNED CIRCUIT WITH THE CIRCUIT INDUCTOR WOUND ON A LONG FERRITE ROD. THE ENTIRE INSTRUMENT MUST BE SHIELDED TO PREVENT ELECTRIC FIELD INTERFERENCE. THE SENSOR USED IS DESCRIBED IN THE 16^THEDITION OF THE ARRL ANTENNA HANDBOOK IN THE TRANSMISSION LINE AND ANTENNA MEASUREMENTS SECTION ENTITLED AN RF CURRENT PROBE.
30	DLM CURRENT PROFILE MEASUREMENTS.
31	CURRENT PROFILE METER IN PLATFORM WAITING TO BE RAISED AND LOWERED TO MAKE CURRENT PROFILE MEASUREMENTS ALONG ANTENNA LENGTH
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33	CURRENT PROFILE MEASUREMENTS OF DLM ANTENNAS
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37	DLM ANTENNA BANDWIDTH BANDWIDTH OF DLM ANTENNAS IS MEASURED AT THE BASE OF THE ANTENNA. THE CRITERIA FOR BANDWIDTH HAS BEEN SET AT A 2:1 SWR. THESE PARAMETERS ARE ARBITRARY AS DLM ANTENNA HAVE SEVERAL BANDWIDTH DEFINITIONS AS WILL BE EXPLANIED. BESIDES THE 2:1 SWR BANDWIDTH THERE IS THE AMPLITUDE AND PHASE BANDWIDTH. THE AMPLITUDE AND PHASE CHARACTERISTIC OF A DLM THRU RESONANCE IS LINEAR AND CAN BE DEPICTED BY VISUALIZING THE UNIVERSAL RESPONSE CURVE FOR A TWO POLE BANDPASS FILTER HAVING LINEAR PHASE AND AMPLITUDE RESPONSE.. SINCE THIS RESPONSE IS OF THE UNIVERSAL SHAPE THE ANTENNA PERFORMANCE CAN BE PREDICTED AND UTILIZED WELL BEYOND THE 2:1 SWR BANDWIDTH. THE THIRD BANDWIDTH CRITERIA IS LOSS BANDWIDTH. DLM ANTENNAS WILL FUNCTION QUITE WELL WITH SWR RATIOS AS HIGH AS 8:1 OR MORE. THIS IS BECAUSE THEIR RADIATION RESISTANCE IS SO HIGH. HOWEVER NOT EVERY AMATEUR TRANSCEIVER CAN TOLERATE SUCH A HIGH SWR. A TUNER FUNCTIONING AS LINE FLATTENER WILL ALLOW DLM OPERATION WELL BEYOND THE 2:1 SWR BANDWIDTH. SINCE COAX LOSSES AT LOWER FREQUENCIES (1.8--10 MHZ ) ARE NOT SEVERE THE POWER DELIVERED TO THE ANTENNA WILL ONLY BE DECREASED BY A FEW TENTHS OF A DB.
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43	"BANDWIDTHS ASSOCIATED WITH HIGH FREQUENCY..." BANDWIDTHS ASSOCIATED WITH HIGH FREQUENCY DLM ANTENNAS ARE GENERALY 2% TO 5% OF THE OPERATING FREQUENCY. THERE ARE SOME EXCEPTIONS AND THESE ARE STILL BEING INVESTIGATED. TO IMPROVE ANTENNA BANDWIDTH AT THE SACRIFICE OF A SLIGHT DECREASE IN RADIATION PERFORMANCE, A FALSE WINDING CAN BE INTERLACED WITHIN THE PRIMARY HELIX WINDING. THIS ALSO HAS A SIMILAR EFFECT WHEN APPLIED TO LOAD COILS. THIS FALSE WINDING MAKES NO ELECTRICAL CONNECTION ON THE HELIX OR LOAD COIL. THE BANDWIDTH ENHANCEMENT HAS BEEN A FACTOR OF 2 WHILE DECREASING RADIATION PERFORMANCE BY ABOUT -1.0dB. TO UTILIZE THIS EFFECT THE FALSE WINDING CONDUCTOR MUST BE OF THE EXACT SAME MATERIAL AS THE HELIX OR LOAD COIL PRIMARY WINDING MATERIAL.
44	AMPLITUDE AND PHASE BANDWIDTH OF DLM ANTENNAS UNIVERSAL RESPONSE CURVE SEE RADIO HANDBOOK, FREDERICK TERMAN, 1943
45	UNIVERSAL RESPONSE CURVE
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52	"USE OVERHEADS FOR ADDITIONAL SWR..." USE OVERHEADS FOR ADDITIONAL SWR CURVES
53	WHAT ABOUT RADIALS? DLM ANTENNAS WORK WELL ON SHORTENED RADIAL SYSTEMS. TYPICALLY THE USE OF 1/8 WAVE LENGTH RADIALS IS RECOMMENDED BUT THE AREA AROUND THE DLM ANTENNA FOR A DISTANCE EQUAL TO THE ANTENNA HEIGHT SHOULD HAVE A VERY DENSE CONCENTRATION OF RADIALS SOME SCREEN MATERIAL.. WHAT HAS BEEN FOUND TO WORK WELL IS 16 1/8^TH WAVE LENGTH RADIALS WITH A DENSE COVERING OF SCREENING IN THE IMMEDIATE VICINITY OF THE DLM AND EXTENDING OUT FROM THE CENTER FOR A LENGTH EQUAL TO THE DLM ANTENNA HEIGHT FROM BASE TO LOAD COIL. THIS IS WHERE THE HIGHEST CONCENTRATION OF ANTENNA CURRENT ALONG THE DLM IS LOCATED. DLM ANTENNAS PARTICULARLY LIKE NON-RESONANT VERY DENSE GROUND SYSTEMS LIKE METAL COATED ROOFS AND THE HULL OF SHIPS OR ANY LARGE NON-RESONANT HIGHLY CONDUCTIVE SURFACE.
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55	A 40 METER DLM ON A WIRE SCREEN GROUND PLANE
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58	VHF DLM ANTENNAS THREE DIMENSIONAL DLM ANTENNAS CAN BE USED AT VHF FREQUENCIES UP TO 200 - 300 MHZ. BEYOND THESE FREQUENCIES THE HELIX DIMENSIONS MAKE FABRICATION VERY DIFFICULT. THIS PART OF THE PRESENTATION WILL DICUSS ONLY THREE DIMENSIONAL DLM TECHNOLOGY AS APPLIED TO VHF FREQUENCIES
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63	SOME VHF DLM ANTENNAS THE FOLLOWING SLIDES ARE VARIATIONS OF SOME OF THE VHF THREE DIMENSIONAL ANTENNAS.
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67	THE SPIRAL TOP HAT DLM THE PLANO TOP HAT DLM COMBINES THE TOP HAT AND LOAD COIL IN ONE STRUCTURE. THIS ANTENNA CONFIGURATION ALLOWS FOR MAXIMUM UTILIZATION OF THE ENTIRE ANTENNA WITH MAXIMUM CURRENT PROFILE EXTENDING FOR NEARLY THE ENTIRE LENGTH OF THE ANTENNA. BANDWIDTH AND EFFICIENCY OF THIS CONFIGURATION HAS BEEN IMPRESSIVE. BANDWIDTH EASILY EXTENDS BEYOND THE ENTIRE 40 METER BAND AND EFFECIENCIES HAVE BEEN MEASURED IN THE HIGH 80% TO 95% AS COMPARED TO A ¼ WAVE MONOPOLE ON THE SAME GROUND SYSTEM
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71	THE PLANOSPIRAL DISTRIBUTED LOADED MONOPOLE THE PLANOSPIRAL DISTRIBUTED LOADED MONOPOLE WAS DEVELOPED FOR APPLICATIONS OF DLM TECHNOLOGY INTO UPPER VHF,UHF AND MICROWAVE FREQUENCY REGIONS. THIS IS A COMPLETELY PLANAR ANTENNA IN THAT IT IS TWO DIMENSIONAL. THIS DESIGN RETAINS ALL THE CHARACTERISTICS OF THREE DIMENSIONAL DLM WHILE ALLOWING IT TO BE FABRICATED USING PRINTED WIREING BOARD AND THIN FILM FABRICATION TECHNIQUES
72	SOME EXAMPLES OF PLANOSPIRAL DLM ANTENNAS
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77	THE HIGH FREQUENCY PLANOSPIRAL DLM TO PERFORM MEASUREMENTS ON THE VERY SMALL PLANOSPIRAL DLM AT FREQUENCIES OF 250 AND 500 MHZ HAS PROVEN TO BE VERY DIFFICULT WITH THE CURRENT EQUIPMENT ON HAND. TO OVERCOME THIS PROBLEM THE 250 MHZ PLANOSPIRALDLM WAS SCALED FROM 250 MHZ TO 7 MHZ. THIS HAS PROVEN TO BE A BETTER TEST ENVIROMENT AS EQUIPMENT TO MEASURE CURRENT PROFILES AND OTHER PARAMETERS WAS READILY AVAILABLE THE MEASUREMENTS PERFORMED INDICATED THAT THE PLANOSPIRAL DLM BEHAVES IN EVEY DETAIL LIKE THE THREE DIMENSIONAL DLM IN EVERY CATAGORY
78	SCHEMATIC DIAGRAM OF HF PLANOSPIRAL DLM
79	CURRENT PROFILE PLANOSPIRAL DLM
80	REACTANCE AND RESISTANCE AS FUNCTION OF FREQUENCY
81	SWR BANDWIDTH OF HF PLANOSPIRAL DLM
82	OUTLINE DRAWING PLANOSPIRAL HF DLM
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86	FEEDING A DLM AS PREVIOUSLY MENTIONED THERE ARE NO MATCHING NETWORKS NECESSARY FOR CONNECTING TO A DLM ANTENNA. A DIRECT 50 OHM COAX IS ALL THAT IS REQUIRED. IN SOME OF THE DLM VARIATIONS A SERIES CAPACITOR IS USED. THAT IS THE EXTENT OF MATCHING DEVICES REQUIRED.
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88	MAKING HIGH FREQUENCY DLM ANTENNAS AS MENTIONED EARLIER THE BASIC DLM ANTENNA IS MADE UP FROM 4 BASIC ELEMENTS MID-SECTION HELIX ASSEMBLY LOAD COIL TOP-SECTION
89	ASSEMBLY OF BASIC DLM ANTENNA
90	THE HELIX THE HELIX IS A LONG COIL WOUND ON A FORM OF SUFFUCUENT STRENGTH TO KEEP THE WHOLE ASSEMBLY STABELIZED THE HELIX SUPPORTS THE UPPER PARTS OF THE DLM ANTENNA AND IS THE MOUNTING PLATFORM FOR THE ANTENNA
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92	HELIX MATERIALS THE PREFERRED MATERIAL FOR THE HELIX IS FIBERGLASS HOLLOW TUBING. THE NEXT BEST MATERIAL IS PVC TUBING SCHEDULE 40 THESE ARE NOT THE ONLY MATERIALS THAT CAN BE USED BUT ANY GOOD INSULATOR THAT WILL SUPPORT THE HELIX WINDING CAN BE USED.
93	WINDING THE HELIX THE HELIX CAN BE WOUND WITH A VARIETY OF MATERIALS. MATERIALS USED TO DATE THAT HAVE GIVEN GOOD RESULTS THIS FAR HAVE BEEN COPPER WIRE**** COPPER BRAID FLEX WEAVE COPPER STRAP
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95	40 METER DLM WITH BRAID WOUND HELIX
96	WINDING THE HELIX WINDING THE HELIX CAN BE DONE BY HAND BUT THE MACHINE SHOWN WORKS MUCH BETTER. HOWEVER THIS IS A CONSIDERABLE INVESTMENT FOR BUILDING ONE ANTENNA. THE SMALLER DLM’S LIKE THE 40 AND 30 METER AS WELL AS THE HIGHER FREQUENCIES ANTENNAS CAN ALL EASILY BE WOUND BY HAND, EVEN WITH COPPER STRAP. THE 80 AND 160 DLM HOWEVER ARE ANOTHER MATTER. WINDING A 160 METER DLM HELIX WITHOUT THE AID OF SOME FORM OF HOLDER IS ABOUT NEAR IMPOSSIBLE. THE BEST WAY TO WIND THESE ANTENNAS IS TO CONSTRUCT A BEAM OF 2x4 LUMBER AND SUPPORT IT ON A COUPLE OF SAW HORSES. THEN SUPPORT THE HELIX AT EACH END WITH SOME SORT OF ARRANGEMENT SUCH THAT YOU CAN ROTATE IT BY HAND. I HAVE DONE THIS ROTATING WITH MY RIGHT HAND AND FEEDING WIRE WITH MY LEFT HAND. YOU WILL NEED A SUITABLE CLAMP FOR SECURING THE WINDING MATERIAL WHEN YOU NEED TO TAKE A BREAK. IT IS A SLOW PROCESS THIS WAY BUT MUCH CHEAPER.
97	HELIX WINDING INFORMATION BELOW IS A TABLE OF HELIX WINDING INFORMATION FOR SOME OF THE LOWER HAM BANDS BAND HELIX HELIX WINDING MATERIAL TURNS METERS LENGTH DIA LENGTH # 160 16ft 3.5in 15.25ft WIRE 154 160 16ft 3.25in 15.25ft ½ W x .020 145 COPPER STRAP 80 8.0ft 2.0in 7.5 ft 3/8 W x .020 119 80 8.0ft 2.5in 7.5 ft 3/8 w x .020 100 40 48 in 1.25in 46 in WIRE 110 40 48 in 1.25in 46in BRAID 98 40 48 in 1.25in 46in 1/4W x .020 96 30 36.5in 1.0 in 33in ¼ IN cpr braid 80 30 36.5in 1.0 in 33in #14 flexweave 80
98	HELIX INDUCTANCE THESE ARE THE HELIX INDUCTANCE YOU SHOULD HAVE AFTER WINDING THE HELIX. THESE SHOULD BE WITHIN 10% 160 46uh 80 20uh 40 10uh 30 7.0uh NOTE: FOR TOP HAT VERSIONS DECREASE INDUCTANCE BY ½ TOP HAT SPOKE LENGTH FOR 40 METERS IS 30 INCHES. SCALE AS REQUIRED FOR OTHER BANDS
99	TOP AND MID-SECTIONS ALUMINUM IS BY FAR THE BEST MATERIAL FOR EITHER THE TOP OR THE MID-SECTION WIRE DLM ANTENNAS HAVE BEEN BUILT WHERE A HELIX AND LOAD COIL HAVE BEEN SUSPENDED FROM TOP AND MID SECTIONS MADE OF COPPER WIRE.
100	MID-SECTION DIAMETER AND LENGTH 160 2.Oin 14ft 80 1.0in 7.0ft 40 1.0in 42 in 30 7/8 in 29.1in
101	ANTENNA CURRENT AS FUNCTION OF MID-SECTION LENGTH THIS GRAPH INDICATES VARIATIONS OF CURRENT PROFILE AS MID-SECTION LENGTH IS VARIED. FOR THIS TEST THE POWER WAS HELD CONSTANT AND THE ANTENNA WAS RESONATED EACH TIME TO RESONANT FREQUENCY AT WHICH TEST WAS BEING PERFORMED
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103	TOP-SECTION LENGTH
104	LOAD COIL LOAD COILS ARE WOUND WITH #10 STRANDED PVC COVERED OR PLASTIC JACKET WIRE. THE 160 METER LOAD COILS HAVE BEEN WOUND WITH #10 OR #8 STRANDED WIRE 160 METERS LOAD COIL INDUCTANCE 70-75uh 80 LOAD COIL INDUCTANCE 30 uh 40 LOAD COIL INDUCTANCE 15-16 uh 30 LOAD COIL INDUCTANCE 10 uh THE LOAD COIL CAN TAKE ON ANY SHAPE YOU DESIRE. SELECT LOAD COIL DIAMETER AND CALCULATE USING STANDARD SOLENOID CALCULATIONS FOR COIL INDUCTANCE WITH SELECTED LENGTH AND DIAMETER
105	SOME SUGGESTED LOAD COILS THE FOLOWING ARE LOAD COIL DIMENSIONS AND WINDING LENGTH WITH INDUCTANCE 80 METERS COIL FORM 2.O in PVC PIPE O.D. =2.5in WINDING LENGTH IS 7.5 in AND WOUND WITH 36 TURNS #10 PVC COVERED WIRE. INDUCTANCE IS 30uh
106	MATERIALS 160 METER HELIX FORM USING FIBERGLASS IS 3.5 inches O.D. THIS FIBERGLASS HELIX FORM IS FIBERGLASS PIPE USED FOR THE PETROLEUM INDUCTRY. WALL THICKNESS IS VERY THIN BUT IT IS VERY STRONG. ALSO REINFORCED WITH EPOXY AND SPIRAL STRIPS OF FIBERGLASS CLOTH ARE USED INTERWOUND AROUND CIRCUMFERENCE AND ALONG LENGTH.
107	AMERON SPECIFICATION SHEET
108	MAX-GAIN SYSTEMS MAX-GAIN SYSTEMS IS A SUPPLIER OF FIBERGLASS TUBING AND OTHER MATERIALS MADE OF FIBERGLASS. THEY HAVE SQUARE TUBING, ROUND ROD AND A VARIETY OF OTHER PRODUCTS. THE WILL SHIP MOST ANYWHERE IN THE USA. HAVE LENGTHS CUT TO 4 FEET AS 8 FEET IS MIN. LENGTH OR YOU WILL PAY A LOT FOR SHIPPING
109	MAX-GAIN PRICE LIST FOR ROUND FIBERGLASS TUBING
110	A WORD ABOUT FIBERGLASS TUBE AND PVC PIPE FIBERGLASS TUBING: FIBERGLASS TUBING FROM MAX GAIN SYSTEMS HAS A FINISH THAT MUST BE ROUGHED UP BEFORE COATING WITH EPOXY OR EPOXYING INTO END FITTINGS. THE EPOXY COATING AND FIBERGLASS PIPE MUST BE PAINTED TO PREVENT UV LIGHT DETERIORATION. THIS IS DONE AFTER THE HELIX MATERIAL HAS BEEN WOUND AND COATED WITH EPOXY. FOR SUPERIOR STRENGTH UNDER ALL CONDITION THIS MATERIAL IS RECOMMENDED BUT IN SMALL QUANTITIES IS VERY EXPENSIVE PVC SCHEDULE 40 PIPE SCHEDULE 40 PVC PIPE CANNOT BE EPOXIED TO END FITTINGS. THIS MATERIAL WILL NEED TO FASTENED TO ALUMINUM END FITTING BY DRILLING AND TAPING FOR MACHINE SCREWS. IT IS SUGGESTED YOU USE STAINLESS STEEL HARDWARE TO PREVENT CORROSION. SCHEDULE 40 PVC PIPE WILL BECOME BRITTLE IN COLD WEATHER AND CAN CRACK UNDER HEAVY STRESS OR SHARP BLOWS.
111	Applications Applications Loops Dipoles DLD Arrays Phased arrays Parasitic yagis
112	APPLICATIONS THE BASIC DISTRIBUTED LOADED MONOPOLE ELEMENT CAN BE CONFIGURED INTO MANY OTHER ANTENNA APPLICATIONS. THESE HAVE INCLUDED. DIPOLES LOOPS PHASED ARRAYS CLUSTERS OF DLM ELEMENTS YAGI ARRAYS DRIVEN HORIZONTAL AND VERTICAL POLARIZED ANTENNA ARRAYS
113	DIPOLES PLACING TWO DLM ANTENNAS BASE TO BASE FORMS A DISTRIBUTED LOADED DIPOLE (DLD) ANTENNA. YOU CAN ALSO WIND ONE CONTINUOUS HELIX. THE CENTER OF A DLD IS AT GROUND POTENTIAL AND CAN BE FED OFF CENTET BY CONNECTING THE COAX SHIELD TO CENTER AND THE COAX CENTER CONDUCTOR TO THE PROPER MATCHING TAP. LIKEWISE YOU CAN ALSO FEED IT BALANCED WITH A BALUN TRANSFORMER BY SELECTING PROPER TAPS EACH SIDE OF HELIX CENTER. DLD ANTENNAS HAVE BEEN MADE FOR 40,30 AND 20 METERS WITH EXCELLENT PERFORMANCE.
114	DISTRIBUTED LOADED DIPOLE EXAMPLE.
115	DISTRIBUTED LOADED LOOP ANTENNA THE DISTRIBUTED LOADED LOOP ANTENNA IS STILL UNDER GOING REFINEMENT. WITH DLD ELEMENTS IT IS POSSIBLE TO HAVE A CARDIOID INIDIRECTIONAL PATTERN BESIDE A BI-DIRECTIONAL PATTERN. LOOP NULS HAVE BEEN MEASURED IN EXCESS OF -40DB WITH LITTLE EFFORT. THE DLM ELEMENTS ARE MADE TO RESONANT HIGH IN FREQUENCY AND TUNED TO RESONANCE WITH CAPACITOR AT THE TOP OF THE DLM ELEMENTS. THE LOOP SHAPES CAN BE SQUARE OR DIAMOND. FEEDING IS VERY SIMPLE, JUST TAP THE HELIX AS BEFORE FOR A 50 OHM MATCH. CAN BE FEED BALANCED OR UNBALANCED WITH BASE OF DLM ELEMENTS AT GROUND POTENTIAL. CONNECTING TWO DLM MAKES A ½ WAVE LOOP, 4 MAKES A FULL WAVE. A 40 METER DLM LOOP CAN BE AS SMALL 2 FEET ON SIDES A 160 METER DLM LOOP CAN BE 12 FEET SQUARE OR EVEN 8 FEET SQUARE. LOOPS FOR OTHEWR BANDS OF INTEREST CAN BE NESTED INSIDE ONE ANOTHER.
116	DLD LOOP ANTENNA
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118	40 METER DLM LOOP ANTENNA
119	PHASED ARRAYS PHASED ARRAYS OF 2 DLM ELEMENTS HAVE BEEN DESIGNED AND BUILT FOR BOTH 40 AND 30 METERS.
120	40 METER 2 ELEMENT PHASED ARRAY USING DLM ELEMENTS
121	"NOW FOR INFORMATION ON USING..." NOW FOR INFORMATION ON USING THIS TECHNOLOGY THIS IS PATENT PENDING TECHNOLOGY OF THE UNIVERSITY OF RHODE ISLAND KINGSTON. YOU ARE ALLOWED TO BUILD THESE ANTENNA BUT ONLY FOR YOUR OWN USE AND EXPERIMENTATION. YOU MAY NOT DO ANY OF THE FOLLOWING. YOU MAY NOT BUILD MORE THAN ONE AND SELL THEM,GIVE THEM AWAY OR MANUFACTEUR THEM WITHOUT FIRST OBTAINING A LICENSE FROM THE UNIVERSITY OF RHODE SLAND, THE URI FOUNDATION. BOTH ACTING AS AGENTS FOR THE STATE OF RHODE ISLAND. DOING ANY OF THE ABOVE WILL INFRINGE ON THE PATENT AND RESULT IN LEGAL CONSEQUENCES FAR GREATER THAN YOU MAY EXPECT.
122	"THE END" THE END THANK YOU FOR YOUR INTEREST
123	"THE FOLLOWING INFORMATION IS COPYRIGHTED" THE FOLLOWING INFORMATION IS COPYRIGHTED