Hello Jakko,
Yes indeed PJ12, I have replaced the fets and have an offset off about 10 volts !! that is not good. i am now thinking that the ne5534an ic's (2 on top off each other ?) are also bad. I removed and checked all the other semiconductors but they are all in good shape, so I am a bit in a dead end over here.
Do you have any suggestion for me ?
Yes indeed PJ12, I have replaced the fets and have an offset off about 10 volts !! that is not good. i am now thinking that the ne5534an ic's (2 on top off each other ?) are also bad. I removed and checked all the other semiconductors but they are all in good shape, so I am a bit in a dead end over here.
Do you have any suggestion for me ?
is there ~0V DC offset on the other channel? if so, make comparison measurements between the same components on the different channels, starting with the input stage and working toward the OPS. when a reading on one channel differs significantly from the same reading on the other channel, you are homing in on the problem.
This was the first time in many years I had a styroflex with a short never had this before. So I was al the time looking in the wrong way.
Hi guy's, just to be sure I just phoned a friend of mine who also has the PJ12 and got him so far to open up the case and inside also the two NE5534 on top of each other.
Any way it is not some sort of modification he is the first owner.
I do find it rather strange the only thing i can think of is that the opamps can deliver more to the rest of the cicuit
Greetz René.
Any way it is not some sort of modification he is the first owner.
I do find it rather strange the only thing i can think of is that the opamps can deliver more to the rest of the cicuit
Greetz René.
Hi Per,
They are indeed a bit hot not to much but you can feel it very well with your finger, about 45 degrees or so. They run on +- 15 volt rails.
Would love to have the schematic and maybe it is an idea to replace the Ne's with a better opamp AD, OPA etc. ????
What is inside is 2SK389, BD902, BD901, 2SB649, 2SD669, two NE5534 and three 2SK135 and three 2SJ50. And of course powersupply with two bridge rectifiers and a lot of small capacitors, not much special but somehow they managed to get it sounding very very good. Normally I listen to an Audio Research D100B or an Hawk Audio A60 hybrid but i was very supprised with the PJ12 .
Ther must be something special about it?
René.
They are indeed a bit hot not to much but you can feel it very well with your finger, about 45 degrees or so. They run on +- 15 volt rails.
Would love to have the schematic and maybe it is an idea to replace the Ne's with a better opamp AD, OPA etc. ????
What is inside is 2SK389, BD902, BD901, 2SB649, 2SD669, two NE5534 and three 2SK135 and three 2SJ50. And of course powersupply with two bridge rectifiers and a lot of small capacitors, not much special but somehow they managed to get it sounding very very good. Normally I listen to an Audio Research D100B or an Hawk Audio A60 hybrid but i was very supprised with the PJ12 .
Ther must be something special about it?
René.
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