MDS Testing July 2007

N.E.W.S. MDS and ERP Testing
At the annual N.E.W.S. picnic, we do MDS (Minimum Discernable Signal)
and ERP testing on 10 GHz and 24 GHz, and possibly higher bands someday.
To test for MDS, we set up a distant signal source. After everyone has a
chance to peak up on the signal, the signal level is reduced one dB at
a time - when you can no longer hear it, then you have found the MDS for
your system. You decide how well it works, and whether you can hear as
well as Don and Dale. As a doublecheck, the frequency is moved a few KHz,
then the signal level is increased one dB at a time (this is the "backup"
number. If you weren't kidding yourself, you should be able to find it at
the same level as before. Usually, it takes a few more dB to find a signal.

Finally, we also check relative ERP, transmitting one at a time and
recording the relative power received at the distant point.
Results in 2007 were pretty good, with 11 participants on 10 GHz 
and 4 on 24 GHz, plus a couple of higher frequency stations for show.
This isn't a competition, just a chance to check out the gear with
friends around to help. Most folks had 10 GHz stations that worked
pretty well, while a few found problems to fix before the 10 GHz &
Up contest in August. Not only do we know our equipment works, but
also that there will be some other good stations to work.

NOTE: one callsign was not recorded by the scribe. 
Please let me know who it was.

               
  North East Weak Signal Group            
  Annual Picnic - 14 July 2007            
               
  Test results - 10 and 24 GHz            
               
CALL RIG 10 GHz MDS     10 GHz ERP    
    lost backup        
               
K2AEP 18" offset, 110 mw -102 -86 dBm -18 dB  
KA1OJ 24" offset, 6 w -104 -96 dBm -1 dB  
W1FKF 18" offset, 200 mw -102 -99 dBm -20 dB  
AF1T 24" dish, 10 w -104 -94 dBm 0 dB  
W1MKY 12" dish, 2.6 w -80 -76 dBm -17 dB  
WW1Z 20 dBi horn, 600 mw -80 -78 dBm -24 dB  
? 18" offset, 10 mw -90 -87 dBm      
W1GHZ 18" offset, 1 watt -92 -80 dBm -18 dB  
N1EKV 24" dish, 400 mw -91 -79 dBm -14 dB  
W1AUV 18" offset, 1.7 w -95 -87 dBm -16 dB  
W1RT 24" dish, 10 w -90   dBm      
               
               
    24 GHz MDS     24 GHz ERP    
               
N1JEZ 20" dish, +32.5 dBm -96 -92   0    
W1FKF 18" dish, 600 mw -88 -86   -8    
KA1OJ 24" dish, 1/2 w -93 -90   -6    
W1GHZ 18" dish, 2 w -94 -83   -3    
               


Last Updated on 11/8/2007
By Paul Wade W1GHZ