[600MRG] Noise phaser update

[Dave Riley]

For those who are drenched in QRN, here is an updated and simplified 
twist of Dallas Lankford's phaser by N1KPR..

https://lh3.googleusercontent.com/proxy/JwfKtJC5dkzMr3y0y4Nczeavhv5m4l_yj3J9I-yiOtGRAnZiqzQt4lhaRn2Ye0-nTAoCf8_ht7615IYlADa8Wmn0Y-czjUNk4UClsdi4NIjK7hi4jNyb4Qoc_I7hBU2NDOr0DfZc7g

I find that 490 / 518 / and 531 khz sigs most useful from the east 
coast.. First two are Navtex and 531 AM station is either Faroe Islands 
or the Iberian peninsular..
The north Atlantic 490 Navtex does not conform to known schedule... Easy 
to see that they are generally northeast..

#1 antenna here is a 400' vertical loop
#2 ( noise ) antenna is a 300' loop on ground directly beneath the 
vertical loop..

Also, when 531 AM station starts popping up is good propagation 
indicator... Usually gets to 25 dbm above noise and ZERO with phase 
switched..

The phase reversal switch is from the loop on ground.. Tune for minimal 
sigs on known carrier, flip switch and see up to 20db ( so far ) from 
here...