1. A TECHNICAL BRIEFING FOR AMATEUR RADIO OPERATORS
“VERTICAL COLLINEAR ANTENNAS: BETTER THAN A DIPOLE?”
PRESENTED TO:
ARASWF
NAPLES, FL 34119
JANUARY 2017
PRESENTED BY:
DR. AL TORRES
KP4AQI

2. January 2017: “Vertical Collinear Antennas: Better than a Dipole?”
For Year 2017
January 2017: “Vertical Collinear Antennas: Better than a Dipole?”
February 2017: “How to See Radio Frequency (RF) Waves: the Carbon Magic”
March 2017: “ Classical Modulations: The New Zero Bandwidth Concept ”

3. PRESENTATION OUTLINE
WHAT IS A VERTICAL COLLINEAR ANTENNA?
VERTICAL COLLINEAR ANTENNA ATTRIBUTES
VERTICAL COLLINEAR ANTENNA CONFIGURATION
COMPARISON OF DIPOLE ANTENNAS WITH VERTICAL COLLINEAR ANTENNAS
VERTICAL COLLINEAR ANTENNA COMPUTER PROGRAM
BUILDING A VERTICAL COLLINEAR ANTENNA
SUMMARY

4. WHAT IS A VERTICAL COLLINEAR ANTENNA (VCA)?
The VCA is a rugged antenna, an omnidirectional collinear, it is capable of surviving harsh environments. It's a good choice for repeater installations and can be top, or side mounted to the tower
You can obtain approximately dB of gain over a dipole, depending on the number of elements you use. The higher the gain the narrower the elevation pattern
The main elements are constructed from ½ wavelength sections of coaxial cable. You can also do the elements of ¼ wavelength coaxial sections
You can “house” the coax sections inside a PVC pipe and allowing the top ¼ wave bare section above the PVC pipe

5. VERTICAL COLLINEAR ANTENNA ATTRIBUTES
Higher gain function than a typical dipole
If half wavelength sections are used it will be independent from a ground plane
Vertically polarized
Good Impedance Matching to 50 ohm coaxial line (low VSWR)
Efficient Radiator if made from Copper material
Simple to fabricate; can be encased in PVC pipe

6. VERTICAL COLLINEAR ANTENNA CONFIGURATION

7. COMPARISON OF DIPOLE ANTENNAS AND VERTICAL COLLINEAR ANTENNAS

8. VERTICAL COLLINEAR ANTENNA COMPUTER PROGRAM
Vertical Collinear Antenna Calculations AT.xls

9. BUILDING A VERTICAL COLLINEAR ANTENNA FOR VHF
Computer Program lets you select the operating center frequency (e.g / MHz) and coax sizes
Construction made from popular coax units. Can use RG-213 with a propagation velocity factor of 0.66
Can have multiple elements; elements can be quarter wave type or half wave types
If you use half wave type elements, antenna is ground independent

10. JOINING THE VERTICAL COLLINEAR ANTENNA ELEMENTS

11. COAX PREPARATION FOR THE VERTICAL COLLINEAR ANTENNA

12. VERTICAL COLLINEAR ANTENNA 5 ELEMENT PATTERN

13. THREE ELEMENT VERTICAL COLLINEAR ANTENNA PATTERN

14. SUMMARY WE HAVE DEFINED VERTICAL COLLINEAR ANTENNAS
COLLINEAR VERTICAL ANTENNAS ARE MORE EFFICIENT THAN DIPOLE ANTENNAS (HIGHER GAIN)
COLLINEAR VERTICAL ANTENNAS ARE EASY TO FABRICATE; DESIGN CALCULATIONS ARE PROVIDED BY THE KP4AQI EXCEL COMPUTER PROGRAM
CAN BE FABRICATED FROM ANY SIZE COAX PROVIDED THE PROPAGATION VELOCITY OF THE COAX IS KNOWN. SIZE OF THE COAX DICTATES THE POWER HANDLING OF THE ANTENNA

15. MORE INFORMATION or COPY OF PRESENTATION
SEND AN TO THE FOLLOWING URL:
CONTACT ME AT:
AL TORRES
KP4AQI
P. O. BOX 24283
DAYTON, OH