[600MRG] Try QRSS60: Up to 20dB advantage over WSPR. Part I of 2.

[James Hollander]

    I invite Part 5 ops to postsome one-hour QRSS60 operating times on this reflector and see who’s interestedin receiving QRSS.  I’d sure like to havemore QRSS receive opportunities. 
    Use the appended Formula tosee what TX power in dBm you may need for QRSS. Confirm your TX can handle QRSSduty cycle at the often-lower QRSS power level. Test to see how much you canbeat the Formula and still get your QRSS received. I’ll update the Table ofConstants for the Formula as your experience teaches us. 
   Why QRSS is Important.      
     630m at night: If USA hams ever get a 630mband FCC-approved, a lot of us with less power and antenna space may end upradiating 100mw or less. Part 5 can be leaders. QRSS is easy to send anddelivers remarkable distance per watt compared to WSPR. QRSS can become one ofthe popular 630m modes especially at night. QRSS60 may offer 20dB over WSPR. 
     DX: 1w or 5w QRSS60 probablycan span oceans more often and more months of the year than WSPR does. Thereceiving station just needs to know what freq and QRSS mode speed to look for.
     Daytime: 1w to 5w QRSS60probably can regularly deliver ground wave farther than WSPR.  Solar-flare days may give a far greaterQRSS60 range than even the enhanced distances already reported for WSPR on suchdays. 
   I look forward to any interested comments or words of wisdom. 
    73, Jim H  W5EST    
Formula/Chart to findQRSS TX Power to Reach a Remote Receiver 
     Formula: 
                      Pqrss# = Ptxwspr +SNRwspr – C#    
Add up your WSPR TX Power (dBm) and your negated WSPR SNR (dB) at thatreceiver. Look up your WSPR SNR at that receiver on http://wsprnet.org/drupal/wsprnet/spotquery prior to your QRSStest run. Then use the TABLE below and subtract the constant C#(dB) for yourQRSS mode speed. The result is recommended QRSS TX power in dBm. 
     EXAMPLE: WG2XIQ’s 37dBm (5w) gets -22dB WSPRSNR one evening at W5EST. 
WG2XIQ can use at least 17dBm (50 milliwatts) QRSS60 TX power and alsoget through to W5EST. 
      Pqrss60 = 37dBm + 22dB –42dB (C60).  Pqrss60 = 17dBm (50mw). 
  
TABLE OF CONSTANTSFOR QRSS POWER FORMULA* 
MODE#     CONSTANT C# 
QRSS3    C3 = 30dB 
“  10       C10 = 34dB  
   20       C20 = 37dB  
   30       C30 = 39dB  
   60       C60 = 42dB 
 120      C120= 45dB       
  600     C600= 52dB 
1200    C1200=55dB