darkdruid
New member
I have 2 PFO AQ2-175 dual ballasts with Ushio 20k bulbs. The bulbs fire but never get very bright. As far as I can tell, the ballasts are the older probe start and the bulbs are the newer pulse start. Even though the ballast fires them, they are weak. PAR readings only 14 inches below the bulbs are less than 20. Will the older probe ballast not run the pulse bulbs? I thought the difference was in the starting, not the running. Could it be a bad ballasts? I have 2 of them and it's the same on both. Any clues?
