Well, I got my new 400 W bulb in the mail on Tuesday. I put it in the
next day and things still don't look right. The bulb just isn't bright.
The light that falls on the plants still looks white, just like my pure
MH light in the other room of the basement. When the combo fixture was
new, the light made the plants look a funny yellow color. The sodium
bulb isn't putting out enough light to do that now.
I guess I need a new ballast. :-( Does anyone happen to know if the
output of a HP Sodium ballast can be tested with an electronics meter?

Steve


Steve wrote:
A question.
How do high pressure sodium bulbs tend to burn out?
I've used a 400 W MH fixture for several years. I've replaced a few MH
bulbs and they just burn out like any other bulb. Three or 4 years ago I
got a sun systems fixture with a 400 W MH AND a 400 W HPS together in
the one fixture. I remember thinking how yellow everything looked under
the new light.
This week, all the plants came in. About the 2nd day, I realized the
plants didn't look yellow now. Things looked about the same as the MH
only fixture. I peered under the hood and found the HPS bulb still
working but glowing a deep orange that wasn't very bright.
Is this how they die of old age? Don't even tell me the ballast is going
bad!

Steve