W0IVJ's recent post to this reflector coincidently provided links to
products I was in the process of installing here. I promised an update after
I had a chance to try these products in the field.
Several weeks ago the neighbors across the street, who are about 750 feet
from most of my antennas, installed a 1000 watt HPS grow light in their
greenhouse. This thing fired up about an hour before my sunrise and shut
down about an hour after my sunset. It tore up 160, 80 and 60 meters. As it
warmed up you could watch a wide band of S9 noise travel across the spectrum
scope trying to decide on the multiple places it wanted to land for the day.
The ballast was a no-name import designed by Satan himself.
I had heard good things about the "Revolution Ballast EMI Filter" available
from Hydrofarm so I elected to try that first. I didn't want the increased
liability of installing a homebrew filter on someone else's property, so a
commercially available filter looked like a great option. The filter
attaches to the lamp (load) side of the ballast and does not provide any
filtering on the AC input side. Unfortunately, this filter did not reduce
the noise from this particular installation by any significant amount.
The more expensive option was to offer to replace the offending ballast.
While it was not my responsibility to do so, it was far and away the most
expedient and effective way to handle the issue. After a bit of digging
around I found the "Galaxy Grow Amp Model 902220". I purchased it from a
local vendor who offered to take it back if it did not solve my problem.
These are also available from online sources for far less than the MSRP
shown in the link below. Galaxy advertising touts "ultra low RFI broadband
emissions" and several vendors recommend these to growers who would like to
minimize an RF signature recognizable by law enforcement. There's an
emissions test report by a third-party lab posted on the Galaxy website.
Galaxy maintains the following: "All Galaxy brand electronic ballasts
legitimately pass FCC Article 18 Part B standards. This standard allows for
much less radio frequency & electromagnetic interference than Part A. (277
volt Galaxy ballasts are tested to Part A commercial standard). Part B level
certification confirms FCC compliance not only for commercial applications,
but for residential as well."
Keep in mind I am a fair distance from the source, but when compared to the
original installation the improvement with the Galaxy ballast is remarkable.
The new ballast was installed without the "Revolution Ballast EMI Filter",
by the way.
I should point out that the neighbor was very cooperative and gave me total
access to his greenhouse (veggies and house plants, for those wondering).
It's a good thing the problem was resolved when it was. They are thinking
about building a bigger greenhouse and indicated they would use the Galaxy
ballast if and when they buy additional grow lamps. Had I not intervened
there may have been several more of Satan's toys to deal with.
Hope this helps someone in a similar situation. As always, Your Mileage May
Vary.
Links:
Revolution Ballast EMI Filter - http://tinyurl.com/hclaw3m
Galaxy Grow Amp Model 902220 - http://tinyurl.com/hx59v5z (click on the FCC
docs button for information on EMC testing)
Galaxy Grow Amp Model 902220 emissions test report -
http://tinyurl.com/hlp9g9k
Larry K5RK
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