Problem with speedball upgrade

[xiawei]

The transistors were possibly damaged by the A1/A2 short and may need to be replaced. You can request more at [email protected]

Thank you Doc!

You mean both the MJE350 and 2N2907?  Anyway to test them?

 

[Paul Birkeland]

You mean both the MJE350 and 2N2907?  Anyway to test them?

If you replace them, and the board works, then they were bad

Really though, it's no problem to assist with some replacement parts, the transistors are sensitive enough that it's a good idea to replace them both and not worry about one failing later.

 

[xiawei]

You mean both the MJE350 and 2N2907?  Anyway to test them?

If you replace them, and the board works, then they were bad

Really though, it's no problem to assist with some replacement parts, the transistors are sensitive enough that it's a good idea to replace them both and not worry about one failing later.

Thank you all for the great helps I got here! I'm ordering replacement now.

 

[xiawei]

Sorry Doc just one more question! I switched the pc boards although A3 lights now but the sounds of both channels are gone. Before the switch the right channel sounded fine to me.

Could anything else be wrong?

 

[Doc B]

Could anything else be wrong?

Sure, but you need to make this fix before you move on to other issues.

 

[xiawei]

The transistors were possibly damaged by the A1/A2 short and may need to be replaced. You can request more at [email protected]

Sent an email yesterday. How can I know the order was received?

 

[xiawei]

Got the parts! The shipping was fast! Amazing service! Thank you Bottlehead!

I'll install them either later today or tomorrow. And post the result here...

 

[xiawei]

Could anything else be wrong?

Sure, but you need to make this fix before you move on to other issues.

Thank you Doc for quick delivery of the parts. Unfortunately, after replacing both transistors on that small board, nothing changed! A3 LED still doesn't light up.

When the bad board was on the right side, terminal 5 read 0v and terminal 9 read about 50v. Now after switching of the boards (bad one on the left) and replacing of the transistors, T1 reads 0v and T7 reads 55v.

I'm puzzled! Please guide me!

Have a great weekend!

 

[xiawei]

Looks like it's the small board. But what also can go wrong with it? Or something else that is beyond my understanding? Please help.....

 

[Paul Birkeland]

When we get our next batch of boards in, we can send you a single replacement board and all the parts.  (Since this has been narrowed down to be the issue)

I'd shoot an e-mail to replacementparts(At)bottlehead(doht)com

-PB

 

[xiawei]

When we get our next batch of boards in, we can send you a single replacement board and all the parts.  (Since this has been narrowed down to be the issue)

I'd shoot an e-mail to replacementparts(At)bottlehead(doht)com

-PB

Thank you so much! The edge (looks like cut from a bigger board) of this board indeed looks rough compared to the other good one. Now I'm bit confident that I should be able to make it sing again...

Just in case you need, my original order# is 1390065690. My name is Wei Xia.

Thanks again for the help!