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

2002 Antenna Gain Results

Tested in Milwaukee, WI - July 26, 2002


144 MHz CallDesignGain (dBd)
WA9KRT10 ele K5GW 17 ft.12.6
N9MYKModified 5 ele Arrow Antenna7.2
NA0IA6 Ft Cheap Yagi7.1
KD4NOQ2M Endfeed1.8
WB9OGMFull Wavelength Sq.0.3
222 MHz CallDesignGain (dBd)
KB0PE20 ele HB from CC 13B2 boom + CC parts14.1
NA0IA6 ele Cheap Yagi9.4
WA1MKE3 ele Yagi8.3
W0ZQ3 ele HB8.1
WB9OGMFull Wavelength Sq.2.9
432 MHz CallDesignGain (dBd)
K0NYCushcraft 19 ele14.9
KB0OZN15 ele HB K1FO13.1
W0LMD6 ft dish w/Dual Band Patch feed12.0
KD4NOQ7 ele Rolcon RCS7-42011.4
N9MYKMod'd 10 ele Arrow Antenna10.9
KO0Z9 ele K2RIW at 439 MHz10.3
NA0IA6 ele Cheap Yagi6.6
N8KWXM2 HO-Loop3.2
N8KWXEggbeater No Ground Plane1.2
902 MHz CallDesignGain (dBi)
WA1MKE23 ele F9FT18.0
K0DAS21 ele F9FT17.1
KB0OZN18 ele KLM12.9
NA0IA11 ele LoopYagi12.7
KB0OZN10 ele Cheap Yagi with 22 ft of RG213 that could not be removed11.1
K9VNMCom'l Log Periodic8.0
K0DASDouble diamond6.3
N0CIHDouble diamond5.1
K9VNMQuad Array of 7 turn Helix Antennas5.0
1296 MHz CallDesignGain (dBi)
K0DAS55 ele F9FT23.6
NA0IAS19 ele Loop Yagi17.3
N6CL15 ele Yagi16.0
K0DASTwo 3# Coffee Can horn11.1
NA0IA10 ele Cheap Yagi w/22 ft of RG-213 that could not be removed10.2
W0LMD30 turn Helix - 6 dB Axial Ratio10.0
K0DASDouble Diamond8.5
NA0IADouble Diamond8.3
W0LMD1/4 wave vertical2.5
W0LMD4 1/2 turn helix - 8 dB Axial Ratio1.5
2304 MHz CallDesignGain (dBi)
W9IIX45 ele LPY #224.1
W9IIX45 ele LPY #123.6
K0DAS52 ele LPY DEMI23.4
K0GCJ"31-inch" dish18.5
NA0IA21 ele LPY Directive Systems16.6
K0GCJ"24-inch" dish w/loop feed15.7
WA5VJBHuber-Suhner 9 patch array15.4
WD9OWN"12-inch" x "12-inch" pyramidal horn13.2
WD9OWN1# coffee can7.2
K0DAS52 ele LPY DEMI5.4
NE8IPringles can Optimized<-10
NE8IPringles can per CNN Hacker article<-10
2400 MHz CallDesignGain (dBi)
W0LMD7.5' dish w/G3RUH feed - 0.6 dB Axial Ratio37.8 dBiC
W0LMD7.5' dish w/patch feed 2.1 dB Axial Ratio33.1 dBiC
WB9OWN"12-inch" x "12-inch" pyramidal horn13.6
WA5VJBHuber-Suhner 9 patch array13.0
N8KWX16T helix - 2.8 dB Axial Ratio13.2 dBiC
WB9OWN1# coffee can8.2
NA0IADouble Diamond4.8
NE8IThe probe from the Pringles Can!!!1.2
NE8IPringles Can optimized-8.2
NE8IPringles Can per CNN Hacking article< -16
3456 MHz CallDesignGain (dBi)
NA0IADirective Systems 44 ele Loop Yagi20.3
NE8I45 element Loop yagi HB17.3
NE8IPringles Can optimized7.8
NE8IPringles Can per CNN Hacking article5.8
5760 MHz CallDesignGain (dBi)
W0AUS"18-inch" Sony DSS dish with W1GHZ Feed24.7
NE8IPringles Can optimized4.5
NE8IPringles Can per CNN Hacking article1.5
10 GHz CallDesignGain (dBi)
K0GCJ2' dish with penny feed34.0
KM0T2' dish with buttonhook feed33.0
K0KFC"18-inch" DSS dish with W1GHZ feed33.8
WB0LJC"18-inch" DSS dish with 10/24 GHz feed27.6
K0GCJ31" dish with penny feed23.6
KM0TMAComm Gunnplexer Horn17.1
WK9E"2 5/8"" by 2 1/4"" horn16.6
N0UKW2IMU Feedhorn12.2
24 GHz CallDesignGain (dBi)
AA9LDMC 12" Dish33.2
W0AUS10G/24G Dual feed 18" DSS dish31.7
W0AUS18" DSS dish with W1GHz feed31.2
47 GHz CallDesignGain (dBi)
WA5VJBScientific Atlanta Reference Horn27.6
WA5VJBMicrowave Associates 24 GHz Horn26.2

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

144-432 MHz by WB0TEM
902 MHz - 47 GHz by WA5VJB

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