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Uzávěrka / Updated: 1.6.2006 (1 JUN 2006)

Sketchs, plans and photos FM antennas (87,5 - 108,0 MHz)

... now see you english version, author of text: Petr Kružík, JIDXC
translate to english thanks - Jitka Jarošová

If you would like to have good FM-range (87,5 - 108,0 MHz) receipt, it is clear you have to have prime exterior antennas.
Below you can see the best antennas which you can get in our small country. They meet the most exacting criterions for distance receipt, DX-ing. They are hight profitable, ultradirectional. They are characterized in extensive coafficient of back receipt, side receipt´s lobes are minimal. The best solution is former "west-german JÄGER WELLE".
(pict.no. 1a,1b,1c,1d)

It is predetermined fo DX-ing because of the hight profit = GAIN (over 11 dB), ultradirectionality and extensive coafficient of back receipt. Unfortunately based on informations from Pavel Bárty the purchase of this antenna is impossible neither in Germany
(some unfounded traces lead to portal e-bay.) nor in our country. But if you are skilful handyman you can make it by yourself. It is strange that the antenna is generally higher but it is about 10 cm shorter than the best czech antenna „070-GBL Seven-element from Chlumec“.
I can not understand why it is not produced in our country. The reason is maybe the higher price which was between 2500-3000 CZK on the end of ninety.
Only one negative of Jäger is the fall of profit above 104 Mhz (by not changed directionality). The solution can be the shortening of some elements on exact dimensions. You can see below two calculating simulations from Mr. Peter Körner from Swedish Lund which can help us in further orientation: http://www.dxradio.cz/jidxc/stolle_us14.doc

original version JÄGER WELLE antenna
14p. antenne simulation pic.1. 14p. antenne simulation pic.2. 14p. antenne simulation pic.3.
modified version JÄGER WELLE antenna
14p. antenne simulation pic.1. 14p. antenne simulation pic.1. 14p. antenne simulation pic.1.

"070-GBL Seven-element from Chlumec" (pict.no. 2)
is another known and commerial produced alternative. Its profit = GAIN (8-9dB) and directionality are not so good as by Jäger. And also the back receipt factor is not comparable with Jäger. It is the most suitable solution for not skilful and lazy natures. The price is about 1200 CZK on our market.
Not evey man can place on his rooftop (in the better case) on on his balcony (in the worse case) such a those monsters. So, he have to choose some compromise - „S030-FMII Three-element from Chlumec (pict.no. 3).
It has smaller dimensions, quite low profit = GAIN (3-5 dB), not expressive directionality and also lower back receipt element. Based on practical experiences the directionality is almost empty in vertical level.
But it is not big problem by local receipt. The best attribute: it is undemanding and ideal for prefab´s balcony. Its price is about 700 CZK on the market.

Picture no. 1a;1b : JÄGER WELLE "in action"

On following www adresse you can find the catch reached by the neighbourhood of Benešov:http://www.dxradio.cz/jidxc/bandsc_s.htm

Jäger WELLE v reálu Jäger WELLE v reálu

Picture no. 1c : JÄGER WELLE - "Drawing of Construction"

Jäger WELLE

Picture no. 1d : JÄGER WELLE - "Drawing of Mounting"

Jäger WELLE montáž

Picture no. 1e : JÄGER WELLE - "real zoom"

Jäger WELLE v reálu

Picture no. 2a : 070 GBL Supersonic - "Drawing of Construction"

On following www adresse you can find the catch reached by the neighbourhood of Jihlava:http://www.dxradio.cz/jidxc/bandscan.htm

070 GBL Supersonic

Picture no. 2b : 070 GBL Supersonic - "real zoom"

Supersonic v reálu

Picture no. 3 : S030 VKV-FM II - "Drawing of Construction"

On following www adresse you can find the catch reached by the neighbourhood of Jihlava:http://www.dxradio.cz/jidxc/bandscan.htm

S030-FMII


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