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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