Tuesday, March 24, 2009

432Mhz EME Up and running

The 432 Mhz EME set-up is finished and running.

With the 4x25 (by I0JXX) antennae I have a sun noise up to 7.015 db with the KUHNE (MKU LNA 432A) preamplifier attached to the splitter without the antenna relays.

For the moment I am using the Russian antenna relays REW-14,

until the NEW antenna relay, ordered to the SSB Electronics (HF400), comes here.

Inserting the REW-14 relays between the splitter and the preamplifier I measured losses at 1,5 db. When the HF400 comes here, I will test again the sun noise difference between the SUN and the cool Sky. The measurements taken with the Noise meter program and the VK3UM excellent EME Calc program.
A very nice page about the sun noise measurements and antennae performance is the Home page of DJ3JJ, Andreas.
DJ3JJ, Andreas say that with my 4x25 I must have at least 10db Sun Noise. I have to modify my harnesses (the coaxial cable, Ecoflex15) between the antenna dipoles and the splitter to have less losses. Now the length of the 4 coaxials harnesses is 3,80m ... too long for 70cm EME operations.
When I will improve my system by 3db (from 7 to 10 as DJ3JJ says) it is similar to have 8 antennas instead of 4!!!

With this set-up until today I made 8 EME qso's
Any way, there is NOT so much activity on 70cm as in 2m .... unfortunately.

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