Fired up my Mini/30 four channel... seperate power supplies for the Mini & the 30. Big problemo...
One of the A30 channels is 16 volts offset. I haven't cooked anything yet but I reckon this isn't good. All the other channels are ~0.025VDC.
Where do I start?
Thanks
EDIT: This is the BrianGT board...
One of the A30 channels is 16 volts offset. I haven't cooked anything yet but I reckon this isn't good. All the other channels are ~0.025VDC.
Where do I start?
Thanks
EDIT: This is the BrianGT board...
2. Check the input MOSFETs. Most of the time one of them is blown up. They shouild have all the same voltage drops as the good channels.
Q1, Q2, Q3, correct?
I had to desolder these and most likely cooked them up pretty good. Chances are good that I pooched them, eh?
I replaced the input FETs with exactly the same results...
no evident solder bridges or cold joints
Should I disconnect everything connected to the output boards?
For testing, where do I put the probes and what voltage am I looking for, where?
Sorry to be so stupid, this stuff usually works!
no evident solder bridges or cold joints
Should I disconnect everything connected to the output boards?
For testing, where do I put the probes and what voltage am I looking for, where?
Sorry to be so stupid, this stuff usually works!
I had enough output FET's to redo some boards and did some disassembly and reassembly etc. Got the new channel down to 4 mV so that's cool. It was a little wierd that I had this stuff all over the desk and I had no output to speak of and cold chips... I did NOT know they had to be grounded to work?????
Well anyway, other than putting humpty back to gether again, everything is VERY COOL... well actually pretty warm!
Well anyway, other than putting humpty back to gether again, everything is VERY COOL... well actually pretty warm!
I did NOT know they had to be grounded to work?????
you have the output fets grounded?
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