As part of the radio astronomy program, a receiving system is planned for addition to the 4.9 meter dish
   when it is installed (late-summer 2008).  The primary objectives for the 4.9 meter dish is 1296-MHz EME
   and 1420-MHz radio astronomy.

   However, by adding additional feedhorns at the focus of the 4.9m dish this can expand to other frequencies.
   8.4-GHz has become the standard unmmanned spacecraft communication fequency band used by the NASA Deep
   Space Network (DSN).  By use of advanced DSP software weak signal carriers from those spacecraft are 
   detectable by amateur astronomers using small dishes.  The process is much the same as receiving EME or
   SETI signals.

   I have acquired some surplus PLL "brick" oscillators and a watkins-Johnson double-balanced mixer for 6-10
   GHz by which a microwave downconverter may be assembled.  Recently I purchased a G3WDG low-noise amplifier
   and a pre-tuned 8-GHz brick oscillator for assembling a 8.415 to 415 MHz converter.

   I have a WR-138 waveguide-coaxial transition to interface a preamp (LNA) to a stanadard WR-138 feedhorn.
   So most of the components needed to assemble a 8415-415 MHz receiving converter are in hand.

   Below is a block diagram for the DSN 8.4 GHz Receiving Converter.  

   
























   
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