Ham Radio

Amateur radio VHF DX methods

Amateur Radio

Since 1982 John and Jane have been licenced radio amateurs holding these callsigns: John: G6LYU, G4XEN, EA7IT, Jane: G6SXU, G4XEM, EA7JK
Current calls are G4XEN and G4XEM.

EA7IT  – Croatia Telegraphy Club member #  2.872

John was most active on the 144 MHz band enjoying weak signal working. In the UK he worked plenty of “DX” (long distance contacts) never using more than 100 watts and a 14 element parabeam. Contacts were made using the following modes of propagation:
Tropospheric – occurs in stable weather, high pressure conditions when radio signals are refracted around the earth’s curvature allowing longer distance communication than the normal 150-250km in “flat” conditions.
Sporadic “E” layer – occurs mainly in summer months when patches of ionisation occur in the “E” layer about 60km above the earth’s surface, allowing sometimes fleeting contacts, although the signal levels are often very high, like a local contact.
Aurora – Occurs after an event on the Sun, when particle streams collide with  the earth’s magnetic poles, causing ionisation very high up. As the  ionisation is moving, doppler shift causes a rasping signal when using  CW (morse code) or a ghostly rough whisper when using single sideband  transmissions. Hear what this sounds like using Morse code here.
Meteor Scatter – Occurs during meteor showers when meteors strike the earth’s  atmosphere the trail ionises the E layer temporarily allowing signals to travel long distances. Special timed techniques have to be used to make this mode of communication successful, and the use of high speed morse code (at 1000 letters per minute) is helpful too. Decoding of high speed morse at my receiving station was achieved using a Uher 4 speed tape recorder.
You can listen to John’s signal – part of a contact recorded by Denis F6CRP