RFI
[Top] [All Lists]

Re: [RFI] MFJ 5008 ultrasonic receiver

To: Hisashi T Fujinaka <htodd@twofifty.com>, HankP <pfizenmayer@q.com>
Subject: Re: [RFI] MFJ 5008 ultrasonic receiver
From: Michael C Martin <mike@rfiservices.com>
Date: Sun, 22 May 2016 16:42:00 -0400
List-post: <rfi@contesting.com">mailto:rfi@contesting.com>
As long as you aren't trying to locate a specific light bulb on a pole you'll be OK! There are two things to find concerning RFI sources on a pole, that's sparking and corona. The biggest obstacle is to be able to differentiate between the two and focus on the sparks. That's not too difficult. The biggest mistake is not utilizing RF receivers to confirm the correct source pole before using the ultrasound.

Sent with AquaMail for Android
http://www.aqua-mail.com


On May 22, 2016 12:16:08 AM Hisashi T Fujinaka <htodd@twofifty.com> wrote:

I haven't actually confirmed this completely, but I think my MFJ
detector picks up a lot of RF that is above ultrasonic. Pointing it at a
fluourescent fixture picks up a lot of buzz.

I bought it as an experiment, figuring I have plenty of $200 toys that
are less than useful. I wish you were closer (I'm in Portland, OR)
because I'd just let you try mine out.

On Thu, 19 May 2016, HankP wrote:


Bob -- I built the ULAD that was in QST some years ago and bought a parabolic reflector from Edmunds --I can hear birds - crickets my steps walking down the alley - two finger rubbed together at 200 feet - the wind blowing if any wind - in all the time I have had it I have been able to identify 1 piece of hardware on a pole . BTW I fiddled with a couple other 40KHZ rx approaches - but essentially same results.

The APS RFI guys have the RADAR ENGINEERING ultrasonic receivers and they are very marginally better than my homebrew.

They have a receiver now that is very effective - They can record the waveform of the noise you hear - (they prefer to record from your antenna ) then go in search of that matching waveform. If I was going to spend any serious dollars on finding powerline arcing - I would do someting that duplicates that ability .

I have tuned loops - and an ICOM R10 rx which is pretty effective but nowhere near as good as the APS receiver . Have you looked at W0IVJ's VDSL recording with a SDR -- that plus some way to record the waveform would be great .

73 Hank K7HP



----- Original Message -----


June QST has a review of the MFJ 5008 ultrasonic receiver. I am
thinking about getting one for locating sources of power line noise.
What do you think of this unit ?

Bob
K6UJ
_______________________________________________



_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi


--
Hisashi T Fujinaka - htodd@twofifty.com
BSEE + BSChem + BAEnglish + MSCS + $2.50 = coffee
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi


_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi

<Prev in Thread] Current Thread [Next in Thread>