"
RF Interference
The next test was to measure RF interference. To do this we first placed the ballast at four feet from our radio and gave a rating according to the amount of interference for both FM and AM radio stations. Then the ballast was then placed 30 feet from the radio and the same process was repeated. Our results are as follows
4ft AM 4ft FM 600w Lumatek Moderate Interference.
none
600w Galaxy Extreme interference (Cannot hear radio transmission) when bulb fires (lasts about 30 seconds), Once bulbs has fired and the lamp is being maintained RF interference is High (Can hear radio broadcast but with considerable static).
none
750w LumatekModerate Interference for 2-5 seconds while the ballast first fires bulb. No interference after bulb successfully fires.
none
1000w Evolution Moderate Interference
none
30ft AM 30ft FM 600w Lumatek Slight interference (Radio broadcast is clear with a slight amount of interference in the background).
none
600w Galaxy Slight interference (Radio broadcast is clear with a slight amount of interference in the background).
none
750w Lumateknone
none
1000w Evolution Slight interference (Radio broadcast is clear with a slight amount of interference in the background).
none
Customers should avoid all digital ballasts that do not have RF shielded lamp cords. The RF interference from these digital ballasts is substantial. If you do not see a metal shield between the outer coat and the wires on the inside of the lamp cord, the cord is not shielded. Digital ballasts do not interfere with FM radio stations but do cause static on AM stations. The better quality digital ballasts, such as the Lumatek, cause the least amount of interference. It should be noted here that the 750w Lumatek ballast we tested was of their latest revision. Ironically, this revision does not utilize an RF shielded lamp cord; Lumatek claims that this is due to internal changes made to the ballast that make the RF shielding unnecessary, and as you can see by the test results, it produced virtually no interference after the first few seconds. Lumatek claims that all of their ballasts will utilize this same construction in the near future.
Regarding out Testing
BGH ran these tests in an effort to address the tons of questions we receive each week from our customers regarding digital ballasts and their true performance versus their stated performance. The tests were not designed in any way to slander some manufacturers or promote others. The problem that we, as well as our customers, faced was that every ballast manufacturer whose ballast we have tested over the years had made claims that were either exaggerated or simply not true. The only way to know for sure was for us to conduct the tests ourselves. Granted, we did not have access to some of the expensive equipment that the manufacturers did, but what we have found is that you can use certain equipment to run certain tests on a certain ballast to produce results that look favorable or poor, it just depends on how the tests are run, what criteria is used, etc. Obviously, if a manufacturer runs a test and doesn't like the results, they are not going to advertise them. They may, however, run a different test and if they like those results publish those instead. The point is, there are many different ways to “skin a cat” when it comes to testing digital ballasts, and we just used the testing scenarios that were available to us (look, you can have the most expensive RF interference testing equipment available that tells you a ballast is clean, but if you turn on a radio 30 feet away and experience interference, that’s got to tell you something!)."
Source -
http://www.bghydro.com/BGH/static/articles/0506_digiballasts.asp
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More info -
https://www.rollitup.org/advanced-marijuana-cultivation/125462-digital-ballast-rf-interference.html
http://www.icmag.com/ic/showthread.php?t=45072
http://forums.cannabisculture.com/forums/ubbthreads.php?ubb=showflat&Number=1554840&page=1
http://www.altair.org/emc.html
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There are threads all over the web about ppl having the exact same problem with older unshielded ballasts.. I will find them and post them later. A cable worker came to my home at 2 am to tell me something in my home was causing widespread outages of cable modems.. Lying? ok w/e dude. Im pretty sure it was because I was using a grounded outlet that was not actually ground ( did not know this before hand ) and/or had the cord too close to my internet cable..