[600MRG] A report for those who are considering getting active on 630m...

[sbjohnston at aol.com]

I received a question about the ground system for my inverted-L antenna.  The ground side of the antenna is just my regular station ground.  The central ground point is along a section of wall where the all the utility service entrances are located. This central ground is a few feet of 1/2" copper pipe with 1" copper straps connecting to the power entrance ground, an 8' rod driven right outside the house, the iron and copper water pipes (before and after water meter), and the metal HVAC ductwork in my house.    To this ground system I have connected to this (with more 1" copper strap) the operating desk star ground, my two Gates BC-1T transmitters, the 630m transmitters, and the shields of all my various antenna feedlines.  

So I made no special ground for the 630 meter antenna system - just made sure its ground side was well-attached to my existing station ground.  The outside of the various coaxial cable shields form accidental counterpoises and radials I'm sure. 



 I also received an email asking about my receive antenna...  My best choices are my 75-meter inverted vee dipole (with the transceiver preamp turned on), or my ground mounted 8' whip with a preamp at the base (preamp off in the receiver).  I've been very diligent about keeping noise sources in my house to a minimum, but neighbors and powerlines do cause noises at times.  I made a 10-foot shielded loop active antenna out of coax inside PVC pipe but it is stored in the garage right now - too unwieldy and has to be turned to peak signals or null noise.


Steve WD8DAS / WH2XHY


sbjohnston at aol.com
http://www.wd8das.net/
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