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

2009 Noise Figure (NF) Results

Tested in Elk Grove Village, IL - July 24, 2009


50 MHzCallDesign DeviceNF (dB)Gain (dB)
K4SMEN2GEEKFPD 750 890.3520.7
144 MHzCallDesign DeviceNF (dB)Gain (dB)
K9LQZ &bnsp;0.3524.7
KL6MHB w/relaysMGF 13020.4519.6
K9PWHB w/relaysMRF 9660.4817.2
KL6MHB w/transco & smaMGF13020.5719.5
KA9VGGHB LN2 0.7035.0
KA9VGGHB LN1 0.8534.6
K0AWUDEMI 1.4021.2
K9LQZARR 1.7713.4
K9LQZCommercial 1.8032.0
KA9VGGHB A2 2.8125.7
KA9VGGHB A1 3.4025.4
WA9FIHLandwher 4.5212.2
222 MHz - none tested
432 MHzCallDesign DeviceNF (dB)Gain (dB)
K4SMEHB N2GEEKFPD 750-890.4022.1
KA9VGGHBLN-1 LP 7500.6134.3
KL6MHB w/transco & smaMGF 13020.8015.7
AF4JFDEMIATF 101360.8016.8
N5VYNARR P43VDG 2.0116.9
902/903 MHzCallDesign DeviceNF (dB)Gain (dB)
W9SZHB FPD 750 @ 6V0.9021.1
1296 MHzCallDesign DeviceNF (dB)Gain (dB)
K8EBG4DDK kitNE3240.2639.2
K8EBW7CNKATF 360770.3935.4
KL6MHB W7CNKATF 360770.3934.7
KA9VGGHBLP 7500.6329.6
K9SRBDEMI Troy ME 0.6516.6
K9SRBDEMI Troy ME 0.7412.6
W9SZHBFPD 750 0.9518.0
WA9FIHSSB SP-23GaAsFet1.5718.4
2304 MHzCallDesign DeviceNF (dB)Gain (dB)
KL6MDEMI W5LUAATF 360770.4518.2
K8EBG4DDK kit 0.7023.6
VE3ADQConifer PA1033 1.4111.1
KA9VGGHB LN2 1.5721.6
KA9VGGHB LN1 1.7522.1
KA9VGGHB A2 2.1324.1
KA9VGGHB A1 2.1825.3
3456 MHzCallDesign DeviceNF (dB)Gain (dB)
K8EBG4DDK kit 0.9422.6
K8EBLUA 0.9413.5
KA9VGGHBLN-1 LP 7506.1512.0
5760 MHzCallDesign DeviceNF (dB)Gain (dB)
KL6MJCA Tech 0.9231.7
10368 MHzCallDesign DeviceNF (dB)Gain (dB)
KL6MJCA Tech 2.2612.5
VE3ADQJCA Tech 3.3534.2
24192 MHzCallDesign DeviceNF (dB)Gain (dB)
W9XAW2PED @ 5V 2.2128.4
K9PWHB XVTR 3.9026.9
WA2VOIW0EOM 4.2315.8
WA2VOIW0EOM  4.9315.8
47088 MHzCallDesign DeviceNF (dB)Gain (dB)
VE4MAW0EOM Surplus 3.4017.5
VE4MADB6NT 472XP 5.037.0
W5LUAAMMC 6241 5.1515.3

Testing by: W5LUA and WA8RJF
Equipment Supplied by W5LUA and K9PW
Measurement Accuracy +/- 0.2 dB at 10 GHz and below
Compiled by WA8RJF and W9GA

14.22 MHzCallDesign DeviceNF (dB)Gain (dB)

Go to top