
I am trying to repair Minelab Relic Hawk from my friend....
Earphone conector touched by accident battery conector, so Q301 transistor blowed up!
It is designated as Q301.....SOme friend told me that it is BC517...but when i tried it it blowed again...
Later it showed that original transistor has label as " TR51 PH7..."
But it is not BC517 or does not have same pin assinments.....
Tracing pcb showed pin order as E C B.....
I also changed LM339 (smt....huh!). Again no progress. I stucked on that damn transistor....
I tried 2N2222 and it not blowed (respecting different pin ***.) but it is not working either.
I can hear some silent "blah,blah" from ears....with 2N2222 on it...
So .....?
Any tip,hint?
Schematic posted on this forum is not accurate....Many things are not matched.....For example instead LM339, there is LM393 on schematic...etc.etc...
All powers are right! I have all the voltages correct...Nothing else warming up on finger check....
I was thinking only Q301 and asuming LM339 can blow in accident case, nothing else should...
So people help!

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