200cm parabolic dish

How everything started...

The history of this antenna starts on the top of the TV-broadcasting tower of Hamburg/Germany where it resisted the elements for almost two decades serving as a directional linka dish. Luckily OM Frank (DD1XF) preserved the slightly oxidated dish from scrapping. In the end I came into it's posession for a little present. I'd like to thank Frank once more for his neverending patience with my chaotic organisation of transportation!

On the 22 of Octobre 1998 dish and rack finally arrived in Finland. After a short motorboat cruise accompanied by light snowfall, the antenna arrived at the island. From planning through restauration until assembly on the top of the rocky hill almost one and a half year went by. In February 2000 the big moment finally came through. Up to now I 'mis'use the dish for plain TV reception, but my plans include usage as a radioamateur device for fullduplex transmission with 360° rotation and 90° elevation capabilities. As far as that a long and stony way is still to go.

This dish is located on a small Finnish island (Loc.KP42ED) surrounded by the wonderful Saimaa Lakedistrict.

Technical details

diameter: 200 cm
depth: 28 cm
f/d ratio: 0,45
gain @11Ghz 45 dBd
dish net. weight 30 kg

Supply

Coaxcable (buried) 40m TELLU 7, Z=75Ohm, ext. shield. copperpipe, rigid core, diam. 14mm, loss: 23dB/100m @ 2Ghz
Powerline 2x 40m Phone-overhead-cable 4 conduct., steel copper-plating, PE-jacket
Powersupply 2x 18V~ 18V/2A AC
Communication 2 Adern fullduplex telephonecircuit
  2 Adern Datacommunication, controlling (reserved)
Protectionpipe 35m 2.5" PE-pipe to protect supplylines in and on rocky ground

Components

2x LNB 10,7-11,8 GHz T-Hohlleiterverzweigung (H/V) mit Sammellinse, NF=1,1dB
1x Multiswitch 2x4 H/V switching, 4 outputs
1x LNA 18 dB low-noise amplifier 950-2050 MHz

Home Page top (by DL2NET/OH4JZJ April 2001)