Herb. I have a 1025 without internal preamp and can notice an increase in
noise level when it's on with no antennas connected but not s1 level. Doesn't
register on s meters but is audible. Now I have a highly noisy environment here
but the 1025 virtually removes all single point noise on 160 thru 30 meters for
me and it's background noise isn't objectionable or for that matter noticeable
when antenna s connected. There is a lot if dx I don't hear however but suspect
that isn't all noise floor related. I do quite well on 80 with it however
hearing everything everyone else hears. 73 Pete W2PM
Sent from my iPhone
On Jan 5, 2012, at 12:12 PM, Herb Schoenbohm <herbs@vitelcom.net> wrote:
> Wanting to try to phase two end to end Beverages I took several MFJ
> Noise Canceller 1026 and 1025 of the shelf and while trying to evaluate
> their ability I noticed on both unit that even without any antenna
> connected to either input there is a least an S-unit increase in
> background noise. One of the units has a built in pre-amp that that was
> switched off.
>
> My question: Is this normal? Won't that noise increase mitigate any
> improvements I could ever achieve by trying to get a signal enhancement
> from two Beverages pointed in the same direction. Both units do a great
> job of nulling a AM station on the expansion band right off the front
> end of both antennas almost down to the noise. But with the two units
> in the null and the phase switched reversed I was expecting an
> enhancement in that direction but either Beverage produced higher signal
> level when the unit is by-pass by turning it off or with either antenna
> hooked directly to the receiver.
>
> Also my two Beverages that I am trying to phase are end to end. Both are
> 600' long and pointing west. The first one ends where the other begins
> with a spacing of 3 feet and with separate ground rods. I have seen
> plots, models, and gain figures for broadside or side by side phasing of
> Beverages but have not seen anything on end to end attempts. Maybe this
> does not work to any advantage. Right now the only thing I have noticed
> is the increase noise floor when the unit is turned on and the ability
> to null stations from the front, both traits are not needed nor desired.
>
> Any suggestions on this would be appreciated.
>
> Herb Schoenbohm, KV4FZ
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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