Bruce
I work with AC inverters for industrial motor control and their presence
obsoleted one of my competitor's overhead crane radio control product
practically overnight. A simple hand held AM "transistor" radio was placed
within 50' of one of these motor Variable Frequency Drive (VFD) controls and
you could hear the varying frequencies being generated by the IGBT transistors.
The competitor remote controls were operating in the 200-400 KHz band. Pray
for dead calm winds at SR and SS.
Carl AG6X
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Bill Cromwell
Sent: Tuesday, February 11, 2014 1:39 PM
To: topband@contesting.com
Subject: Re: Topband: Low band noise
Hi Bruce,
I assume your noise is on top band (just a wild guess). I will lay on plans
this weekend to drive a ways south with the R-599 on 160 meters AND an AM
broadcast band receiver that allows some directive sniffing to see if the
windmill farm down that way is um... 'polluting'. I haven't looked that far
ahead on the weather forecasts. If it's icy or there is a blizzard this old
goat ain't going there. In the process I suppose I'll find out if my car is
'clean'. I've been lucky so far.
73,
Bill KU8H
On 02/11/2014 03:58 PM, Bruce wrote:
> Getting noise from my NW direction. Does not seem to be local. Started
> wondering what, at distance, could be causing it. At times it seems to have
> a rhythm like a motor.
>
> There are a lot of power generating wind mills showing up. Checking through
> Google, they generate DC and convert to 3 phase AC it with an inverter. The
> frequency and phase of the inverter is controlled with a sample from the
> power grid.
>
> Could their inverters have enough sine wave distortion to have harmonic
> energy?
>
> So my question is: Does anyone have first hand knowledge of interference on
> the low bands from power generator wind mills?
>
> Bruce-K1FZ
> www.qsl.net/k1fz/beveragenotes.html
> www.qsl.net/k1fz/pennantnotes.html
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