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Re: QSC Powerlight 3.4 troubleshooting

Thanks Michael for the info.

I was able to repair the power supply. There was an open trace between the transformer A.C supply legs feeding the two half wave rectifier diodes. 

My previous troubleshooting was in my friend’s warehouse with his D.M.M which was limited to 20khz and the reason why I was not able to read any A.C.

Back in my lab my oscilloscope painted a very clear picture.

 The transformer secondary legs measured 115 kHz, 40 volts peak to peak which was not getting to the rectifying diodes (D707 & D705). Thanks

Franz