Pioneer SX-434 - fuse keeps blowing - #8

[petehall347]

2SD313 60V, 3A, 30W, 8MHz
2SB507 60V, 3A, 30W, 8MHz

 

[petehall347]

MJE1530/31 dont seem to exist

 

[Standard-SX7]

I missed a 0

https://www.mouser.de/datasheet/2/308/MJE15028_D-1811617.pdf

 

[petehall347]

TIP31B
TIP32B
might be a better choice

 

[Standard-SX7]

I got original replacement from ISCSemi.

Installed them, turned the receiver on, voltages are right, and then suddenly the other pair started smoking and burned up.
What's my next step here? why did they blow?

Thanks!

 

[mcdoug3721]

Build a DBT

 

[Standard-SX7]

Build a DBT

a what?

 

[petehall347]

I got original replacement from ISCSemi.

Installed them, turned the receiver on, voltages are right, and then suddenly the other pair started smoking and burned up.
What's my next step here? why did they blow?

Thanks!

are they fastened to the heatsink ?

 

[Standard-SX7]

are they fastened to the heatsink ?

no but they were on less than a minute.

 

[petehall347]

no but they were on less than a minute.

you just found out they burn up if not cooled . best never do that again .

 

[mcdoug3721]

Dim bulb tester. Google it.