Topband: 160M EWE Problems Part 2

[Mark K3MSB]

Good Morning!


Last night was the second night in a row with nice conditions between the
east coast and Europe on 160M.    I took the time to get a cup of coffee
and spend a few hours comparing the Inverted-L and EWE, and recording my
observations.


All Inverted-L data was recorded with the Icom on-board preamps OFF.


All EWE data was recorded with the 20 dB external preamp ON.


The external preamp is an Advanced Research Receiver P1-30/20VD


The EWE is pointed roughly 40 degrees, and the grounds are not connected
via wire.  That means the transformer end is towards Europe, and the
resistor end is towards California -- some of you asked for clarification.


General Noise Floor:

INV-L: S2-S3 spikes above S5

EWE:   S4 steady, no spikes   (Higher than the INV-L !!!!!)



Forward reception:

In the following table,  (S1, S2) means S1 on the INV-L,  S2 on the EWE.

SP5GRM   (S7, S7)

OK2RJC   (S9 , S6)

RA2FV    (S6, S4)

RN3CT    (S7,  S4)

EU3AR    (S5, Below noise level)

UT7NY    (S5,  S4)

EI4KF    (S5,  S4)

YO9HP    (S5,  S5)

UY0ZG    (S5,  S4)


Those stations that were S4 on the EWE were pretty much riding the noise
level and I could hear them, but they were much stronger (and easily
copied) on the INV-L!


Conclusions (perhaps incorrect…..)

A) The noise floor of the EWE can be higher than that of the INV-L.

B) The EWE is NOT suitable for weak signal reception


If A and B above are correct, what’s the point of using an EWE?


I state my conclusions based upon my observations, knowing full well a lot
of you successfully use the EWE antenna,  so I still need to learn more, do
more tweaking, etc.



Back Rejection:   I recorded some stations that should have been off the
back of the EWE (or thereabouts…..  I didn’t check them on QRZ.com,  but just
assumed 8,9 and 7 land stations were behind me…..)

N8 (S9+10 ,  S7)

N7: (S7,  S4)

N8  (S9+10,  S9+10)

N9  (S9,      S7)

N8 (S9+10,   S8)

N8  (S9+20,   S9)


So, I am seeing rejection off the back of the EWE.   It doesn’t happen all
the time, but as I said I didn’t do a search to see where each station was
actually located.


Some of you asked how I know my cable and transformer are good.  I attached
the feedline to the transformer,  then used a resistance substitution box
to put a load on the other end of the transformer.   A 470 ohms resistance
provided an SWR of 1.1.  As I moved the resistance above and below 470,
the SWR moved as expected.   Since the transformer is 9:1,  I felt this
showed the coax and transformer were OKI.


Comments welcome.


73 Mark K3MSB