Two Good Days Spent with Quads
			 
			 
			
		
		
		
			
			[After sending this, I never saw it posted so I re-sent.  Sorry if it's a 
dupe in your newsreader.] 
 
"John Ferrell"  wrote in message 
... 
 
 
  
 Don't overlook that you can parallel two quads to get to 50 ohms as 
 well! 
 
 
OK, I took a mental excursion in that direction.  My first thought is to use 
two runs of RG-62 93-ohm computer drop cable off a t-connector.  This goes 
against my grain -- I've always hated using any t-connectors in a matched 
system -- but I guess the match will be maintained. 
 
My second thought is to literally parallel them at the end of a hunk of 
50-ohm cable.  That feed would need to be crossed over, I think, so the 
fields would be additive.  Easy enough to test it both ways, I suppose.  If 
crossover is needed, what would the pattern look like without it?   Hm-m-m-m 
....  near-field cancellation and no pattern?  Pattern rotation? 
 
Of course I will be trying this next idea even if no newsgroup answer is 
forthcoming:  What happens if I tap off  quad #1 on the side _opposite_ 
where I'm feeding it and connect quad #2 there?  Wouldn't this additional 
load reflect back to feed #1 and lower its impedance toward 50 ohms?  I 
don't know what feed #2 would be.  Perhaps a jury-rig parallel line 
calculated to be 100 ohms would do it. (# 10 AWG wires on 5 mm centers would 
do it.)  Phasing will be an issue. 
[I probably don't have a suitable test environment to tell success from 
failure.] 
 
73, 
"Sal" 
 
 
 
		 
		
		
		
		
		
		
		
		
	
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