10. EWE-antenna

In december 2015 I completed a new antenna for shortwave in the garden!
The construction is an EWE-antenna, based on Koontz concept from 1995.

EWE schema

Since the EWE is known for low signal output, I have constructed the balun (transformer) with 25 turns of trifilar 0,6mm (#23) enameled copper wire on a FT140-43 toroid. The FT140-43 was not the toroid suggested in most articles, but I found a few that had it in their construction! And the usual suggested turns was 9-11 trifilar, certainly not 25! Did I do wrong, would the impedance fail?! In the real world I just can conclude that my EWE-antenna does not need a preamplifier to let me hear stations out there. And the signals are low noise compared to my other antenna systems. Especially on the lower bands, but it can be noticeable even up to 15MHz.

(See also a presentation of the EWE-antenna hold 2017-10-03: Experience of an EWE-antenna presentation 20171003 engl ver ).

Here is the layout for the termination net. The reed relays are closed by neodym magnets placed outside the plastic holder. When the first relay was just inside the opening of the plastic holder, I bent it out to the surface of the holder. Then I made the same procedure with the next relay as it reach inside the opening. By making the relays come close to the surface of the holder, I can use magnets outside the holder to close them. Carbon resistors have the best RF-properties.

Layout termination net ed

The balun is wired as follows:

As antenna line I have used a 3,5 mm insulated copper wire, with 7 strands of 0,57 mm (23# AWG), forming 1,78 mm2 (3,6 kcmil).

After the installation of the EWE-antenna my AR7030 have been spinning around the world! And in march 2016 I have logged transmission sites in 59 countries. Although they are not confirmed with QSL-cards, the verification has only been done via ‘short-wave.info’ and ‘mwlist.org’, I think this is a great success as a start in my DX-career! The verification is done by recording the display and sound on the receiver with a videocamera and at the same time also the information on the appropriate site.  The sound ID from the videocamera has then been extracted and is listed beneath. All those heavy videorecordings are then stored in an archive.

After living in our house for 30 years, now (spring 2020, during the peak of the Covid 19 pandemi!!) its time to move to a flat close to the centre of Härnösand. This means the end of the EWE-era for me. The antenna has been dismantled from the garden and is now in care by another DX-er here in Härnösand.

To be able to DX from our flat I will try to build a loop-antenna, based on Chris Trask’s design “A High Dynamic Range Amplifier for Wideband Active Loop Antennas”, see side 28.
The printed curcuit board has already been etched and the components bought from Mouser!

This is how the transmission sites are located in the world around the EWE-antenna in Härnösand.

1. alaska-sound-id-knls-anchor-point-9615khz-20160105
2. new-zeeland-sound-id-rnzi-rangitaiki-9765khz-20160105
3. madagascar-sound-id-bbc-talata_volonondry-12095khz-20160105
4. india-sound-id-air-bengaluru-9445khz-20160105
5. china-sound-id-cri-kashi-saibagh-13670khz-20160106
6. estonia-sound-id-radio-eli-tartu_sooranna-1035khz-20160108-ed
7. oman-sound-id-bbc-al-seela-6195khz-20150108
8. turkey-sound-id-voice-of-turkey-emirler-12035khz-20160109
9. netherlands-sound-id-grootnieuws-radio-zeewolde_flevoland1008khz-20160109
10. sri-lanka-sound-id-voa-deewa-radio-iranawila-13590khz-20160110
11. singapore-sound-id-bbc-kranji-7465khz-20160108
12. poland-sound-id-polskie-radio-jedynka-solec-kujawski_kabat-225khz-20160112
13. united-kingdom-sound-id-bbc-radio-4-droitwich-198khz-20160113
14. romania-sound-id-srr-radio-romania-actualitati-lugoj_boldur-756khz-20160112
15. ukraine-sound-id-ur-1-persha-prog-mykolaiv_luch-549khz-20160113
16. chech-republic-sound-id-cro-radiozurnal-topolna-270khz-20160113
17. moldova-sound-id-vesti-fm-grigoriopol_maia-1413khz-20160113
18. swaziland-sound-id-twr-africa-manzini-9500khz-20160114
19. hungary-sound-id-kossuth-radio-solt-540khz-20160114
20. botswana-sound-id-voa-selebi-pihkwe-15580khz-20160115
21. usa-sound-id-ewtn-vandiver-15610khz-20160115
22. australia-sound-id-r-australia-abc-shepparton-12065khz-20160116
23. cuba-sound-id-r-habana-cuba-bauta-17730khz-20160118
24. iran-sound-id-vo-islamic-rep-iran-sirjan-6040khz-20160118
25. kuwait-sound-id-r-azadi-r-free-afghanistan-kuwait-19010khz-20160119
26. belarus-sound-id-pershy-national-kanal_radyjo-stalitsa-sasnovy-279khz-20160119
27. ascension-sound-id-bbc-ascension-12095khz-20160119
28. south-africa-sound-id-voice-of-america-meyerton-11900khz-20160120
29. france-sound-id-bible-voice-bcn-christ-gospel-issoudun-17510khz-20160123
30. australia-sound-id-r-australia-abc-shepparton-12065khz-20160116
31. sao-tome-principe-sound-id-voice-of-america-pinheira-6080khz-20160124
32. albania-sound-id-china-radio-international-cerrik-13655khz-20160125
33. thailand-sound-id-bbc-nakhon-sawan-15310khz-20160125
34. united-arab-emirates-sound-id-deutsche-welle-dhabbaya-17800khz-20160126
35. morocco-sound-id-r-meditirranee-int-nador-9575khz-20160126
36. vatikan-city-state-sound-id-santa-maria-di-galeria-15595khz-20160127
37. ireland-sound-id-rte-radio-1-clarkestown-summerhill-252khz-20160129
38. luxemburg-sound-id-rtl-beidweiler-234khz-20160129
39. palau-t8wh-the-harvest-show-palau-medorn-9930khz-20160130
40. denmark-sound-id-dansk-radio-langbolge-kalundborg-243khz-20160130
41. lithuania-sound-id-radio-baltic-waves-int-kauna-sitkunai-1386khz-20160130
42. germany-sound-id-r-liberty-radio-svaboda-biblis-9645khz-20160131
43. japan-sound-id-nhk-world-radio-japan-ibaragi-koga-yamata-9625khz-20160212
44. north-mariana-islands-sound-id-r-free-asia-tinian-island-13735khz-20160212
45. guam-sound-id-ksda-awr-guam-agat-15430khz-20160213
46. bangladesh-sound-id-r-bangladesh-betar-dhaka-9455khz-20160213
47. spain-sound-id-r-exterior-de-espana-noblejas-15500khz-20160213
48. north-korea-sound-id-voice-of-korea-kujang-11635khz-20160214
49. south-korea-sound-id-kbs-world-radio-kimjae-15575khz-20160215
50. armenia-sound-id-twr-india-yerevan-gavar-12025khz-20160221
51. uzbekistan-sound-id-nhk-radio-japan-tashkent-11685khz-20160226
52. taiwan-sound-id-radio-taiwan-int-tamsui-district-9465khz-20160227
53. tanzania-sound-id-zanzibar-broadcasting-corporation-dole-11735khz-20160227
54. philippines-sound-id-r-pilipinas-tinang-9925khz-20160228
55. norway-sound-id-nrk-ingoy-153khz-20160228
56. bulgaria-sound-id-the-overcomer-ministry-kostinbrodsofia-11600khz-20160301
57. greece-sound-id-helliniki-radiophonia-athen-9420khz-20160302
58. indonesia-sound-id-voice-of-indonesia-jakarta-cimanggis-9525khz-20160308
59. vietnam-sound-id-voice-of-vietnam-hanoi-sontay-9730khz-20160320
60. argentina-sound-id-r-argentina-exterior-general-pacheco-15345-khz-20160630
61. belgium-sound-id-rtbf-la-premiere-wavre-621-khz-20161116l
62. brazil-sound-id-radio-nacional-da-amazonia-brasilia-6180-khz-20161117
63.  Tajikistan sound ID, Radio Free Asia, Dushanbe-Yangiyul, 13830khz, 20170420
64. Slovenia sound ID, Radio Murski Val, Murska Sobota_Nemčavci, 648kHz, 20171110
65. Slovakia sound ID, R.Patria Maďarsk_R.Devín, Nitra_Jarok, 1098 kHz, 20180107,
66. Russia sound ID, Radiogazeta Slovo_Pravoslavnoye Radio Sankt-Peterburg, Sankt-Peterburg_Sosnovka, 828kHz, 20180906
67. Egypt sound ID, ERTU Al-Quran al-Karim, Santah, 864 kHz, 20181011
68. Syria sound ID, SRTV 1 Dimashk SRTV Radio Damascus, TartusBesira, 783 kHz, 20181014
69. Cyprus sound ID, Radio Sawa, Cape Greco, 990 kHz, 20181105
70. Israel sound ID, KAN Bet, Tel Aviv_Yavne, 657 kHz, 20181109
71. Saudi Arabia sound ID, Republic of Yemen Radio, Jeddah, 11860 kHz, 20181128
72. Djibouti sound ID, Radio Sawa, Doraleh, 1431kHz, 20190219