On Wed, 21 Dec 2011 16:14:58 -0600 Sam Morgan <k5oai.sam@gmail.com>
writes:
> I haven't built or used one, yet
> but I have often thought it might be a good idea
> to put a laser on one, kinda like pointing a weapon with a laser
I like that idea...might work even with daytime sun....I might
try that on my homebrew detector.
I'd like to see what Jerry K4SAV has come up with RE increased
sensitivity....anybody have a schematic?
73,
Charlie, N0TT
> On 12/21/2011 4:04 PM, W2PM wrote:
> > I have used one which the ARRL RF lab brought down here to address
> a very
> > serious problem. We were able to identify the BOLT on the
> insulators where
> > arcing was coming from, photograph it, attach both the audio file
> and the
> > spectral display unique to each offender and the power company
> still reneged.
> > Until FCC saw this and that was the end of the power company
> resistance.
> > Problem fixed. Those devices are not easy to aim however. You
> need a
> > steady hand and lots of patience.
> >
>
> > On Dec 21, 2011, at 4:10 PM, "John G3PQA"<g3pqa@onetel.com>
> wrote:
> >
> >>>>> On 12/18/2011 2:36 PM, Dave W5UN wrote:
> >>>>>> I'm looking for input from someone who has experienced a
> similar
> >>>>>> situation as I describe below.
> >>>>>>
> >>>>>> About 3 months ago I began experiencing severe noise on top
> band.
> >>>>>> It's a constant white noise which begins to drop off above
> 2.5
> >>>>>> mHz,
> >>
> >>> On 12/20/2011 2:30 PM, David Raymond wrote:
> >>>>
> >>>> Jon. . .great advice, particularly about going to higher
> frequencies as
> >>>> you get closer to the noise source. We've spent considerable
> time
> >>>> chasing noise at our contest station. I addition to using RF
> we also
> >>>> use a high range audio device with a highly directional dish
> antenna
> >>>> which listens in the 20 - 40 KHz range. It is an excellent
> tool to
> >>>> have in the arsenal when you get in close (say, 100 yards or
> so). You
> >>>> can usually pinpoint the noise right down to the specific
> insulator,
> >>>> lightning arrestor, etc. In some cases it would be worth
> borrowing
> >>>> one. 73. .. Dave W0FLS
> >>
> >> (Jon, AA1K): tnx info Dave ....where can those be had?
> >>
> >>
> >> For those who wish to build an ultrasonic detector (or in the
> absence of
> >> DX locate bats!) an article was published by ARRL in 2006
> >>
> http://www.arrl.org/files/file/Technology/PLN/Ultrasonic_Pinpointer.pdf
> I
> >> have built a couple of this design using the Far Circuits pcb and
> they work
> >> well, needs a small parabolic dish and piezo electric detector at
> its focal
> >> point. Also I should mention that Jerry K4SAV has designed some
> >> improvements in sensistivity and mixing if needed.
> >>
> >> re. Dave's noise problem, it sounds bad , not the usual
> switchmode etc.
> >> we suffer on 160m.. Any progress Dave?
> >>
> >> 73 John G3PQA
>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
>
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