Re: CN27S30 and other sharp's design.
Anybody who is famillar with Sharp's typical twin transistor chopper regulator can explain the theory of operation about it?
This one switching in and out pair of coils wound around the exposed flyback transformer's core, said two windings tied together on one end from B+ supply? This one with 9 pin SIP IC, two transistors, two coils, few resistors, and some caps.
This one I'm working on has shorted HOT, pair of this transistor choppers shorted, fuse open (not violently). TV died during power loss according to customer.
I tested the chassis for any reaction after disconnecting HOT and pair of choppers, new fuse. The micro is working and I have 15.7KHz pulses on B of the H. transistor driver. Anything in parts I should replace besides the pair of transistors, HOT and fuse? I checked resistors and they're normal.
Just wanted to understand their unique sharp's designs better.
Thanks & cheers, Wizard