> kokiu dazniu mirga su elektroniniu balastu....manau ne 50Hz

  Reikia ant balasto žiūrėt.

http://www.osram.com/osram_com/tools-and-services/services/faq/electronic-control-gear/ :
Transformer type  Operating Frequency
HTi DALI 150      approx. 20-35 kHz
HT 120 LF         approx. 50 kHz
HT 70 L           approx. 45 kHz
HT 105 L          approx. 32 kHz
HT 150 L          approx. 35 kHz
HT 210 L          approx. 35 kHz
HTM 70            approx. 48 kHz
HTM 105           approx. 40 kHz
HTM 150           approx. 35 kHz
HTN 75            approx. 50 kHz

-- 
  saimhe