Q1 Exploded

[pmk2015]

Hi All

I assembled my kit yesterday Q1 was an 8550 and Q2 is 9014. I applied power to test voltage at TP22 (before soldering jp4) After a few seconds Q1 popped and part of the casing came away.

Please can someone advise what could be the problem.

I will mention that I did not have a 9v supply to hand, so I used a 12v supply as the power supply spec stated 9v DC (8-12v)

Could the 12v supply be the problem?

Thanks

Paul

[Jackie]

No.
I'm using a 12V power supply

[davef]

Are you sure you have a "real" DSO138? Check the value of L2.

[pmk2015]

Are you sure you have a "real" DSO138? Check the value of L2.

There is no markings on L2, is there a way of testing it's value?

[davef]

Check your board first http://www.jyetech.com/forum/viewtopic.php?f=18&t=511.

Seems that wrong value inductors are either common or a fact of life on the counterfeit boards.

You would need an inductance meter. If you do have a counterfeit board perhaps the easiest option is to buy the correct value inductor, a new Q1 and try again.

[pmk2015]

Check your board first http://www.jyetech.com/forum/viewtopic.php?f=18&t=511.

Seems that wrong value inductors are either common or a fact of life on the counterfeit boards.

You would need an inductance meter. If you do have a counterfeit board perhaps the easiest option is to buy the correct value inductor, a new Q1 and try again.

Thanks davef, it would appear I have a fake board. Finding a replacement L2 seems a bit of a challenge.