Hi Mark,
I would be curious if you are getting a significant S-Meter reading using
the external preamp and testing with the antenna disconnected from the
cable?
If so, my guess would be that the Ewe pattern is terribly distorted by its
surroundings, noise is coupling in from other sources - or the noise figure
on the external preamp is too high.
73
Art NK8X
ᐧ
On Thu, Dec 31, 2015 at 10:32 AM, Mark K3MSB <mark.k3msb@gmail.com> wrote:
> 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
> _________________
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