In article
,
stryped wrote:

On Dec 25, 10:05*pm, wrote:
On Dec 24, 9:23*pm, stryped wrote:





I decided after the T 12 lights in my attached garage started having
problems to replace them with T8's.(Electroonic ballasts) Since doing
this, Channel 5 WTVF goes out every time I turn the garage lights on.
It goes back to normal when the lights are off.

I have a rooftop antenna a yagi, on a tower right outside my garage. I
also have on this tower my dish network dish.

I origionally thought it was probably the light and replaced it with
another one from Lowes, but this light did the same thing as well.

Is there a way to diagnose what is causing this or preventing it?

I also have UHF little antennas at varios tv's in the house to be able
to work the remote from another bedroom. (Satelite box). however, for
a test, I unscrewed one of the antennas at the kitchen tv and it made
no difference.

The remotes work at 2.4Ghz, well within the microwave spectrum. *A
leaky microwave oven will affect those, not much else.

If the ballasts are putting out that much RFI, you should be wiping
out AM reception for quite a ways, a cheap transistor radio should
pick that right up. *If they're chink fixtures, not much you can do
except replace them with something better-made. *Another problem,
maybe easier to fix, would be that the ballasts aren't radiating but
putting out a signal down your AC power lines and that's getting into
your electronics that way. *RF chokes and filters can be added to kill
that off, shouldn't have to be done on correctly designed ballasts,
but would be a possible fix. *I had a chink-designed motor control
that tripped the computer's UPS anytime I used it, had to stick an EMI
filter on the power cord to kill that.

Stan- Hide quoted text -

- Show quoted text -

Thing is, I took one light back to lowes and exchanged it and now this
light does it too. It is the commercial stip lights I bought. I really
dont want to buy another ballast. And channel 5 here is broadcast on
VHF.

I assume that the replacement is the same make and model.

US Channel 5 is 76 MHz through 82 MHz, which is way higher than any
reasonable inverter harmonics. For instance, the 20th harmonic of a 20
KHz inverter square wave is 0.4 MHz. So there is a problem in the
ballast design, and I have no idea how this got by the FCC.

I would try a better make and model fixture.


Is there a filter I could install on the coax of the antenna?

Certainly, but it should not be necessary, and the filter may be more
expensive than getting a fixture that does not have the problem.
Shielding an ~80 MHz signal at the likely power level isn't all that
cheap.

I have eight 4-tube T8 fixtures in my shop, and have no such problem.

By the way, how does over-the-air FM radio fare? The FM band is between
TV channels 6 and 7, so if TV 5 is in trouble, the FM band may also be.

And, how is AM band reception?

Joe Gwinn