Topband: Received Signal Strengths

[Ed Sawyer]

The 5NN discussion brought up an interesting subject to me.  Signal
strengths reported on 75M SSB are funny to listen too as people seem to be
in a "mines bigger than yours" competition on how many dB above S9 a signal
is.  Meanwhile their noise floor is probably S7 or more - what's the point?

 

Here at N1UR, on 160, I have switchable T verticals (EU direction and Omni).
I NEVER listen on them.  Nighttime noise floor is typically S5 - 7 in the
winter on them with static crashes well over S9 if there is storming in the
east half of the US (for CW).  I have done some signal strength comparisons
with EU stations and Carib stations vs my beverages.  

 

Typically, on 160M, I leave the preamp off for my beverages.  The received
noise floor for my N/S beverage (on CW) is usually S2 - 3 and for my phased
EU beverages is S0 to S1.  I have found the signal strengths of the received
stations to be 1 to 2 S units down on the beverage and equal or stronger on
the beverage if I turn the preamp on - with usually a rise in the noise
floor by a 1 or 2 S units.  Interestingly, on 80M CW, I usually use the
beverage preamp.  The signal often comes up 3 - 4 S units and the noise only
1 to 2 S units.  I often drop in  some attenuation to make the noise floor
"just" go away.

 

What do others see as the difference in transmit antenna vs low noise
antenna signal strengths?

 

N1UR