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The World Of Loop Antennas

The World Of Loop Antennas. An Infinite Array of Simple Stealth Designs Designs Covering RX & TX Loops For Mobil or Home Compilation By KG6UDW. Loop Antennas 80 thru 6M Easy Wire Shapes. ELECTRICLY SMALL MAGNETIC LOOP ANTENNA.

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The World Of Loop Antennas

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  1. The World Of Loop Antennas An Infinite Array of Simple Stealth Designs Designs Covering RX & TX Loops For Mobil or Home Compilation By KG6UDW

  2. Loop Antennas 80 thru 6M Easy Wire Shapes

  3. ELECTRICLY SMALL MAGNETIC LOOP ANTENNA “Trying to compare comparable things, let us not consider an MLA only as a replacement of a long-wire TX antenna. MLAs function as RX antennas nicely even under QRM and ‘radio smog’ that prevent a ‘large antenna’ from picking up any useful signal. MLAs deserve much wider attention than that the OK ham community gives them.”

  4. ELECTRICLY SMALL MAGNETIC LOOP ANTENNA The Ultimate Solution for Hams with Antenna Restrictions

  5. ELECTRICLY SMALL MAGNETIC LOOP ANTENNA

  6. ELECTRICLY SMALL MAGNETIC LOOP ANTENNA Antenna Q Factor: You’ve probably heard the term “Q factor” tossed around in describing antennas, but maybe you haven’t quite yet picked up on exactly what it means from a practical standpoint. Let’s see if we can get at Q, or quality factor, as it relates to antenna circuits and amateur radio operations without reviewing any college level physics or higher math. When we’re done, you’ll have an intuitive understanding of Q that likely far exceeds that of the average ham!

  7. ELECTRICLY SMALL MAGNETIC LOOP ANTENNA 1942 1937

  8. ELECTRICLY SMALL MAGNETIC LOOP ANTENNA In the grander picture: Beyond ham radio, the quality factor is a value that describes some characteristics of an oscillating or resonating system. In radio we’re mostly interested in electric circuits that do the oscillating, and an antenna circuit is of particular interest as oscillating circuits go. SEE WEB PAGE: http://www.hamradioschool.com/antenna-q-factor/

  9. ELECTRICLY SMALL MAGNETIC LOOP ANTENNA The SWR curve diagram below, that an antenna that operates well over a broad band of frequencies (ƒ2 – ƒ1) is going to result in a relatively low Q value. An antenna that operates well across only a very narrow range of frequencies is going to generate a relatively high Q value.

  10. ELECTRICLY SMALL MAGNETIC LOOP ANTENNA SWR curve diagrams

  11. ELECTRICLY SMALL MAGNETIC LOOP ANTENNA The Handy Loop from Alpha Antenna • Handheld and jaw or tripod mountable • 3 foot wide, • 10-40 Meter, • 30W PEP SSB coaxial magnetic loop antenna. This loop is a favorite of permanent base operators who have limited space or when SOTA, EmComm, RADAR, and other rapid response operators need to quickly deploy & then take down an antenna. • VARIABLE AIR CAPACITOR 10-40 meter Handy Loop with 6:1 reduction

  12. ELECTRICLY SMALL MAGNETIC LOOP ANTENNA • High noise rejection is also one of the favorite features of this antenna design for many operators in RFI prone environments. • Highly efficient but Limited to 20-30watts • Good for CW or Digital Modes. RTTY, PSK 31 or fldigi software. • At low power phone is not the best mode of operation but dig is a great use of this type ant. • Higher power requires a large expensive vacuum capacitor and mechanical drive for tuning. 1.5pF @ voltages as high as 5000KV. Or higher • May require frequent retuning due to limited band width. • Large Horizontal loops where used on ships and land based areas.

  13. ELECTRICLY SMALL MAGNETIC LOOP ANTENNA It is useful to know that the practical advantage of an MLA (MLA size related to a wavelength) is logically higher with longer wave lengths. Naturally, one has to consider the optimum loop size 2a/λ, and an achievable efficiency. It is also useful to know that good magnetic loop antennas may exhibit Q values exceeding 1 000, sometimes even more than 3 000. Such antennas then function really well and their ‘loss’ against a much larger dipole may be insignificant.

  14. ELECTRICLY SMALL MAGNETIC LOOP ANTENNA It is often observed that due to a simpler pointing of a small MLA, the MLA output signal can be larger if the MLA is pointed to the minimum of the dipole radiation pattern. If in an actual QTH it is impossible to build a classical long-wire antenna for the lowest SW bands, then good MLAs can be used as ‘not-ersatz’ antennas. The theoretical model of MLA radiation (a freely available 4NEC2 program) indicates that in certain directions and elevation angles, an MLA can have a real gain higher than that of a normalized dipole.

  15. CHA F-Loop Antenna 80~10M • Newly upgraded CHA F-LOOP Standard Antennas are ideal for RV/camping, hotels, apartments, condominiums, homeowners associations, deed restrictions and CCRs (Covenants, Conditions and Restrictions), Short-Wave Listening (SWL) and other places where it is not feasible to erect a multi-band wire or vertical antenna.

  16. CHA F-Loop Antenna 80~10MBYCHAMELEON ANTENNA Field Packable Design Easy Assembly and Set Up HF Digital signal Limited to 20W

  17. CHA F-Loop Antenna 80~10M 1watt 9413 KM = 5848.97 Miles

  18.  The F-LOOP can be assembled and operated under 3 minutes. • CHA F-LOOP operational details:* Frequency: Now 80-10 Meters * Power: 10W CW or 20W SSB PEP* RF Connection: SO-239 UHF female The CHA F-LOOP antenna system consists of:* CHA F-LOOP matching box* LMR-400 coax cable* 12 ft. RG-58A coax with integrated RFI choke* Coupling Loop* Screw-Together hard-line* Molle-style transport bag • Easy tuning:1 - Peak signal in receive mode with the tuning knob.2 - Adjust for minimum SWR in transmit3 - Repeat these steps whenever changing frequency.

  19. Military use of DDRR loop Ant The Directly Driven Ring Radiator (DDRR) Input from up to four 10,000 Watt auto-tune transmitters http://www.radioexperimenter.us/rm-1976-08/low-band-antenna.html Close-up view of military-type Directly Driven Ring Radiator (DDRR) antenna set up for long range communications tests in the 2.0 to 30 MHz frequency spectrumwith a 50kv tuning Capacitor.

  20. Military use of DDRR loop Ant

  21. SKYLOOP ANTENNA My Loop Antenna • Brand: CHAMELEON ANTENNA • Manufacturer's Part Number: SKYLOOP • Part Type: HF Portable Stealth Antennas • Product Line: CHAMELEON ANTENNA Base HF SKYLOOP Antennas • DXE Part Number: CHA-SKYLOOP • Portable Ant Type: Wire • Portable Ant Power Rating: 1,000 W PEP will produce higher voltage at ends. Need to use insulators. • Portable Ant Connector: SO-239, UHF female • Mounting Clamp Included: No • Antenna Weight: 3.00 lbs.

  22. SKYLOOP BASE ANTENNA

  23. SKYLOOP ANTENNA • Additional Information • Portable Antenna Band • 10 meters • 12 meters • 15 meters • 17 meters • 20 meters • 30 meters • 40 meters • 6 meters • 60 meters • 80 meters • CHAMELEON SKYLOOP specifications:* Frequency: 80 - 6 meters* Power handling: 1,000W CW* RF Connection: UHF female on impedance transformer* VSWR: Antenna tuner required* Length 250 ft.CHAMELEON SKYLOOP antenna systems consist of:* One matching transformer* 250 ft. antenna wire* Two isolation loops* One carabineer* Three insulators Stealthy HF multi-band capable antenna system

  24. ELECTRICLY SMALL MAGNETIC Stealthy LOOP ANTENNA • Weekend project. • Low Cost. • Simple to build, start small. • Components readily available. • Maybe you should give it a try. • The web has a multitude of information.

  25. ELECTRICLY SMALL MAGNETIC Stealthy LOOP ANTENNA

  26. Food for Thought“Be Creative Explore Loop Ant” • Be reasonable. • Be Stealth & CC&R. • Be Practical. • Be it Permanent or Portable. You can use electrically small loops –but please note: Magnetic Loops are the most favored as NIVS antennas at ground level. Take care as high RF voltages +5KV exist on certain parts of these antennas. THANKS FOR WATCHING.

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