Hk Actor A112 transistors blowing

[mr funky]

I think that's just semantics (or is it grammar) - there is, of course, one bias transistor for EACH set of output transistors, not BOTH sets

 

sorry al rephrase that,...

Thanks v, yep been there also and replaced that.

its doing its job as there is only one for both transistors and the other side is stable..

 

 

there is one bd679 for each pair of trannys,

one side is stable ( side not blown ) .

the side that has blown is the bd679 I have replaced, I have also swapped these around with the same effect

I.e 1 side stable and the other slightly moving up and down, at volume 0

 

but when I turn the volume up and then back off to zero both settle back to 7.5 mv then again after a few mins one side starts creeping up.

I have the new pots just waiting to put them in,

keep you posted.

thanks you all very much for your help, what a great forum, very much apprecate all your efforts and time looking at this for me.

if you were in my pub I would get you a beer in ,,, but ya not.. so.. dont worry al drink it for you, :P and al tell ya how good it was later, cheers all.;)

[mr funky]

quote]

 

sorry al rephrase that,...

Thanks v, yep been there also and replaced that.

its doing its job as there is only one for both transistors and the other side is stable..

 

 

there is one bd679 for each pair of trannys,

one side is stable ( side not blown ) .

the side that has blown is the bd679 I have replaced, I have also swapped these around with the same effect

I.e 1 side stable and the other slightly moving up and down, at volume 0

 

but when I turn the volume up and then back off to zero both settle back to 7.5 mv then again after a few mins one side starts creeping up.

I have the new pots just waiting to put them in,

keep you posted.

thanks you all very much for your help, what a great forum, very much apprecate all your efforts and time looking at this for me.

if you were in my pub I would get you a beer in ,,, but ya not.. so.. dont worry al drink it for you, :P and al tell ya how good it was later, cheers all.;)

 

 

UPDATE..

Beer was great !,

im so sorry yall was not there, got you all one in but...I felt cheap, so....decided best to get you two each for all your efforts. ;).

 

ok its been out now to a fair few gigs and its been fab since the new pots were put in.

so the answer is to keep things stable, if you are changing the transistors for any reason while you are in there also upgrade the bias pots for what little it costs.

hope this all helps.

cheers all again