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Old 01-07-2013, 10:05 AM
Barrykgerdes
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Barrykgerdes is offline
 
Join Date: Feb 2007
Location: Beaumont Hills NSW
Posts: 2,900
The ASNSW still has the old Fleurs 16ft dish at Wiruna. This aerial was originally used to look at the hydrogen emissions at 1420 Mhz. It now has has a secondary dipole for the 400Mhz area. However the condition of the rest of the dish is in need of repair.

About three years ago I had a look at the dish that had been ignored for many years do to negative results from all the tests. I salvaged the old dipole and re-built it back to original and it responded well to signals at 1420Mhz. A new 1420Mhz low noise pre-amp was obtained and worked well on bench testing with a test signal and simple dipole. I built a low noise amp for 400 Mhz that also worked on bench tests. The main receiver has become a HP 140 Spectrum analyzer from the 1970's that I provided. The theoretical sensitivity with the preamp should be in the region of -135dbm.

However preliminary testing showed the 1420Mhz pre-amp to be unstable when connected to the dipole and no hydrogen noise was observed when the aerial was pointed at the Sun. No testing was done at 400Mhz

I was physically unable to carry out the required repairs to the aerial due to age and now illness and nothing has been done since.

The project could do with some rejuvenation from an enthusiastic younger group but I can only provide technical advice.

Barry

PS I am also an "old-timer" 53 years Radio Ham VK2ZAH. I never bothered with code so only had a limited licence 'til they changed the rules a few years ago. I now have a full licence with my old call sign. I do have TX/RX equipment for 80m to 432Mhz but seldom even turn the receiver on.
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