Re: Aquatic Plants Digest V2 #410

To: Aquatic-Plants at actwin_com
Subject: Re: Aquatic Plants Digest V2 #410
From: Bob Hoffman <bhoffman at deltanet_com>
Date: Fri, 27 Dec 1996 08:11:43 -0800
References: <199612270839.DAA32033 at looney_actwin.com>

> Subject: Re: ballast interference
> 
> Bob Hoffman replied:
> 
> >>  I have recently come by 2 ice cap ballasts. I have set one up and would
> >> like to set the other one up but I'm running into resistance with family
> >> members as they create a lot of interference{sp} with our tv reception.
> >> Anyone with a solution for this please post or e-mail me.
> >
> >I also have two of these ballasts with the same problem.  In the 5+
> >years I have run these, I have yet to find a solution.  What we need is
> >an electrical engineer to solve this problem.  Any out there?  Or does
> >any know one that can offer a solution that WORKS.
> 
> Unfortunately, if equipment is not designed for low radiated EMI
> (electromagnetic interferance), it can be very difficult to lower the EMI
> with after design add ons. Once the EMI is out of the ballast and on the
> leads (or antennas as they are) it's very hard to contain without a steel
> shell around everything.
> 
> Switching power supplies, which an electronic ballast is, are nortorius EMI
> generators, and low EMI is a primary design condiderstion when they are
> built. Not only must filters be considered, but a lot of attention is paid
> to the switching techniques and transformer design to lower the EMI
> generated.
> 
> EMI filters utilizing ferrite beads and perhaps capacitors are used to
> filter out the interference. The filters are optimized to reduce the
> polluting EMI. This process is usually carried out empirically in a screen
> room with a spectrum analyzer, and a wide assortment of filters. I've never
> done it, but I have a friend that has nursed some video cards through FCC
> testing.
> 
> My suggestion is to sell the ice cap and spend the money on Magnetek's,
> Advance, GE, or Motorola electronic ballasts.
> 
> Paul
> 
> Paul Nicholson              Electronic Imaging Systems, Inc.
> paul at eisusa_com             5148 Commerce Avenue, Unit F
> TEL 805 532 1068            Moorpark, CA 93021 U.S.A.
> FAX 805 532 1065

Paul,
Can you provide further details on those ballasts you recommended
(availability, cost, number of bulbs they can handle etc.).  I'm also
assuming that they do not generate any EMI.  Is that correct?
-- 
Bob Hoffman
Huntington Beach Orchids
http://users.deltanet.com/users/bhoffman/hborchid.htm