Greece AM Theory case studies

Greece AM Theory · Put your knowledge to work in context.

The Greek amateur radio theory examination is the written test that stands between a candidate and an amateur radio licence issued under Greek law, which in turn operates under the ITU Radio Regulations. It is aimed at people who want to transmit legally on the amateur bands - shortwave listeners moving up, electronics hobbyists, emergency-communications volunteers, and mariners or hikers who want reliable independent communications. The Greece AM Theory case studies are 5 cases and about 4,515 words.

10 m end-fed, communal TV aerial, and an angry neighbour

You run 100 W on 28 MHz from a third-floor flat in a suburb of Athens. The antenna is a half-wave end-fed: a 9:1 transformer bolted to the balcony rail, a radiating wire sloping up to a 6 m fibreglass pole, and a 3 m counterpoise lying along the rail.

954 words, about 5 min 2

30 m of RG-58 on 40 m: is the ATU hiding a real loss?

Your 40 m inverted-V is resonant at 7.060 MHz. At the shack you measure SWR 1.2:1 at 7.060, 2.2:1 at 7.000 and 2.6:1 at 7.200 MHz, and the transceiver's internal ATU matches it everywhere in the band.

916 words, about 5 min 3

Image, blocking or cross-modulation in a homebrew 14 MHz superhet

You built a single-conversion superhet for 14 MHz: a broadband input transformer (1–30 MHz), no preselector, a diode-ring mixer, a 455 kHz IF chain with a 2.4 kHz ceramic filter, a product detector and AGC. The local oscillator runs above the received frequency.

888 words, about 4 min 4

13.8 V that isn't: cable drop, scope PEP and a lying wattmeter

Your new 100 W HF kit is fed from a 13.8 V switch-mode PSU rated 22 A continuous, through 5 m of 2.5 mm² two-core cable (10 m of copper in the loop), with a 25 A blade fuse at the PSU. On 20 m CW the transceiver draws 19 A.

878 words, about 4 min 5

A 500 W amplifier, a fortnight in the Netherlands, and a rooftop Yagi

You hold a Greek amateur licence (HAREC-equivalent, call sign SV1ABC) that authorises a maximum transmitter output of 100 W. A friend offers you a 500 W solid-state linear amplifier, CE-marked and covering 144–146 MHz.

879 words, about 4 min