Central States VHF Society

Exploring the World Above 50MHz since 1965

  • Digital Communications

    A great number of exciting new digital operating modes have developed, largely because of the availability of personal computers, soundcards, and advanced software. But amateur digital communication began in earnest in the late 1940's (if you don't count Morse as a digital mode!) when hams worked out techniques of connecting mechanical Teletype keyboard/printers to amateur gear using FSK and AFSK modulation. WSJT has become a very popular tool for digital communications. FSK441 mode is in use for meteor scatter contacts and JT65 is popular for terrestrial communications.More Info
  • EME Moonbounce

    Amateur radio (ham) operators utilize EME for two-way communications. EME presents significant challenges to amateur operators interested in working weak signal communications. Currently, EME provides the longest communications path any two stations on Earth can utilize for bi-directional communications. Amateur operations use VHF, UHF and microwave frequencies. All amateur frequency bands from 50 MHz to 47 GHz have been used successfully, but most EME communications are on the 2 meter, 70-centimeter, or 23-centimeter bands. Common modulation modes utilized by amateurs are continuous wave with Morse Code, digital (JT65) and when the link budgets allow, voice..More Info
  • Aurora and Solar Weather

    The interaction between Earth's magnetic field and Solar particles is a complex and mysterious field of science. The storm events involve high electric currents in the ionosphere and vast amounts electric power affecting to great many things. One of the ways to observe what is happening up there, is to detect the effects of these phenomena to non ionizing long wave electromagnetic radiation - radio waves.More Info
  • VHF Contesting and Rover Operations

    Hams have been putting stations in their cars since the Twenties (1920's that is). Today, there is great satisfaction in facing the challenge of installing a transceiver in our small cars and pick-ups, using somewhat inefficient antennas, and still being able to make contacts with hams thousands of miles away while "tooling" down the highway.More Info
  • Annual Technical Conference

    Every year since 1968, during the last weekend in July, the Central States VHF Society hosts an annual technical conference. There are two days of technical presentations, antenna range gain measurements, noise figure measurements, a flea market, and often times a vendor area. It's a great time to learn about weak signal VHF communications and an excellent place to network and catch up with old friends.More Info

2003 Antenna Gain Results

Tested in Tulsa, OK - July 26, 2003


50 MHz CallDesignGain (dBd)
WD9IVD7 element K1FO Mod9.8
KB0PE4 element HyGain8.4
 Reference Dipole0
144 MHz CallDesignGain (dBd)
KB0PE20 ele Yagi15.0
K3IWK10 ele 17.5' HB12.7
 Reference Yagi12.2
WD5AGO10 ele HB11.8
K5YPVMod'd FM Broadcast 5 ele7.0
KA5ONMFractal HB Broad Band Dipole0.3
W2RSMFJ 1717-0.2
W2RSAEA HotRod-6.7
222 MHz CallDesignGain (dBd)
K3IWK17.5' HB 14 ele Yagi (14.0 at SEVHFS)13.8
 Reference Yagi13.0
WD5AGO12 ele 13' HB Yagi12.8
KB0PE11 ele CC parts Yagi on 12' boom12.6
K5LLL7 ele KLM Scrap Yagi11.6
WD5AGO2 8 ele HB Yagi on 7' boom10.8
432 MHz CallDesignGain (dBd)
KB0HH40 ele HB Yagi on 36' trussed boom17.9
KB0HH25 element HB Yagi on 17' boom16.8
WD9IVD41 ele 34' boom HB ATV (439 MHz) yagi based on a K1FO design15.4
 Reference Yagi15.0
K3IWK22 element on 15.5' boom #114.7
K3IWK22 element on 15.5' boom #2 (16.7 at SEVHFS)14.7
WD5AGO18 ele HB Yagi on 12' boom13.6
W2RSMFJ 171712.7
N9LHD4 ele Com'l WB Yagi10.4
KO0ZCC Boomer Circ9.2
K5LLL6 ele CC6.8
KO0ZM2 432 Ho Loop3.2
W2RSMFJ 1717 Dual Bander-0.2
902 MHz CallDesignGain (dBi)
NN5DX HB 12 ele Yagi10.8
KO0ZDB Products 800 MHz Corner Reflector10.7
K5LLL Com'l 800 MHz Yagi cut down to 9029.9
ND2XAEL H5001 11.5" by 11.5" Horn w/dielectric window9.6
ND2XAEL H5001 11.5" by 11.5" Horn w/o dielectric window9.4
NN5DXCom'l 9 ele Yagi7.5
WA5VJBReference 4 ele Yagi7.5
WA5AGOFAA 1030 Horn 18" x 20"6.5
WA5VJB400-1000 MHz PCB LP6.0
N9LHDVJB 900-2600 MHz LP5.6
W7XU 20 ele Loop Antenna remains (post Tornado)5.3
KD4NOQCom'l 800 MHz 6 ele Yagi4.9
1296 MHz CallDesignGain (dBi)
K5PJR Loop feed 26" x 31" dish18.8
WD5AGO25 ele LoopYagi18.7
KB0PE25 ele LoopYagi16.6
K0GCJ31" dish w/3 turn Helix feed - Not Circular Polarization16.5H / 5.4V
WA5AGOFAA Horn 18" x 20"15.2
ND2XAEL H5001 11.5" by 11.5" Horn w/dielectric window14.9
ND2XAEL H5001 11.5" by 11.5" Horn w/o dielectric window14.7
WA5VJB10 element Cheap Yagi13.0
W0AUS6.7 x 9" Ridged Horn 13" long9.5
WA5VJBReference Horn6.8
N9LHDVJB 900-2600 MHz PCB LP5.8
2304 MHz CallDesignGain (dBi)
W9IIX45 el LPY17.9
ND2XAEL H 5001 11.5" by 11.5" Horn w/o dielectric window15.3
ND2XAEL H 5001 11.5" by 11.5" Horn w/dielectric window15.1
WA5VJB"31-inch" dish18.5
 Reference Horn12.5
W0AUS 6.7" x 9" Ridged Horn 13" long12.1
KA0BVZ30 element HB Yagi12.0
ND2X8" x 6" AEL H5101 Horn 5.5" long11.5
K0GCI31" dish with Helix Feed - Not CP; Horiz was rotated ~30 deg from L-Band measurement10.0H / -4.2 V
WA5VJBTrough Reflector Com'l9.9
WA5VJB2-10 GHz PCB LP5.6
2450 MHz CallDesignGain (dBi)
WA5VJBHuber Shuner 9 ele Slot feed patch array14.5
 Reference Horn13.1 dBiC
KA0BVZ30 element HB Yagi12.1
W0AUS6.7"x 9" Ridged Horn 13" long12.0
N9LHDVJB 900-2600 MHz PCB LP5.6
WA5VJBVJB 2.1-10 GHz PCB LP5.1
3456 MHz CallDesignGain (dBi)
ND2X8" x 6" AEL H5101 Horn 5.5" long16.3
W0AUS 6.7"x 9" Ridged Horn 13" long15.6
 Reference Horn15.5
N9LHD8"x 8" 16 patch array14.4
N0LNOCircular Horn 3" dia 7.7" long6.7
WA5VJB2.1-10 GHz PCB LP5.7
5760 MHz CallDesignGain (dBi)
WD5AGO 8" x 10" Homebrew PCB Horn 18" long20.9
N9LHD12" x 12" Patch array w/64 elements17.5
W0AUS6.7"x 9" Ridged Horn 13" long16.8
WA5VJBARA DRG 4-10 GHz Ridged Horn16.4
ND2X8" x 6" AEL H5101 Horn 5.5" long13.4
W0LNO1.5 inch dia Horn 7" long7.5
WA5VJB2.1-10 GHz PCB LP6.0
10 GHz CallDesignGain (dBi)
W9FZ18" DBS dish with W1GHZ Feed31.7
W9FZSame dish before the tweak31.3
WA2VOI18" DBS dish with Chaparral Feed31.4
WA2VOI18" DBS dish with the 10/24 GHz feed30.9
K0KFCRCA 18" DBS dish with W1GHZ Feed30.0
W0AUSHB 4..5" x 5" Horn 6" long20.3
WA5VJB8" Cassigrain Dish w/Dielectric WG18.3
 Reference horn17.7
WA5VJBARA DRG 4 -10 GHz Ridged Horn13.8
24 GHz CallDesignGain (dBi)
WA2VOI18" DBS dish w/AA6IW Dual band feed37.7
WA5VJBNURAD 12.5" Cassigrain Dish35.2
WA5VJBSci. Atlanta SA 12A-26 WR-28 Horn23.5
WA5VJB8" Cassigrain Dish w/Dielectric WG22.4
 Reference Horn20.7
47 GHz CallDesignGain (dBi)
W5LUA16" Commercial WR-22 Dish42.0
WA5VJBSci. Atlanta SA 12A-26 WR-28 Reference Horn27.6
WA5VJB3" Rexolite 24 GHz lens antenna w/WR-22 feed19.5

Note: The 47 GHz range needs a little more work for next year and more antennas to test!

144-450 MHz by WB0TEM
902-47,100 MHz by WA5VJB with Thanks to WA2VOI

Go to top