unfortunately one channel of my pearl phono stage stopped working and needs some help. First aid indication:
No voltage on Q4 (the ztx 450) next to the 2sk 389. There is a "control point" were I should measure 13,8 V or so. Any hint what that points to?
help is highly appreciated
stefan
No voltage on Q4 (the ztx 450) next to the 2sk 389. There is a "control point" were I should measure 13,8 V or so. Any hint what that points to?
help is highly appreciated
stefan
What is the voltage on either pin of R8 in reference to gnd?
You can measure the 13.6V on the emitter of Q4. The emitter is the one which is not the middle pin and not connected to R14...
You can measure the 13.6V on the emitter of Q4. The emitter is the one which is not the middle pin and not connected to R14...
hi cvi,
late answer.
on R8 i measured 28,1 and 28,6 to gnd.
the same points at the working channel give 28,4 and 28,7. So seems to be the same.
stefan
late answer.
on R8 i measured 28,1 and 28,6 to gnd.
the same points at the working channel give 28,4 and 28,7. So seems to be the same.
stefan
My best guess is that you have burned the 2sk389 (not your fault, but a lot of people have had this problem).
If you don't think that is the problem. Please take the schematics and put all your measurements on the schematics (you can do this is in paint), then I might be able to point you to the problem.
If you don't think that is the problem. Please take the schematics and put all your measurements on the schematics (you can do this is in paint), then I might be able to point you to the problem.
hey cviller, that is veery kind of you. When Leela finished, I´ll also have a look at the schematics and report 😉
![URL]](/community/proxy.php?image=http%3A%2F%2F%5BURL%3Dhttp%3A%2F%2Fimageshack.us%5D%5BIMGDEAD%5Dhttp%3A%2F%2Fimg232.imageshack.us%2Fimg232%2F5664%2Fleelanv5.jpg%5B%2FIMGDEAD%5D%5B%2FURL%5D+%5BURL%3Dhttp%3A%2F%2Fg.imageshack.us%2Fimg232%2Fleelanv5.jpg%2F1%2F%5D%5BIMGDEAD%5Dhttp%3A%2F%2Fimg232.imageshack.us%2Fimg232%2Fleelanv5.jpg%2F1%2Fw350.png%5B%2FIMGDEAD%5D%5B%2FURL%5D&hash=d8930c88a0ad681c7969d2fdf1a2b1dc)
I heard that it is wise to split the source resistors. If i can find another 2sk 389 i´d try it this way.
stefan
stefan
yes, of course, i read that somewhere with the sk 170 substitution. and i got some here🙂
but how to do that will be my tomorrow´s research. huhu, i dip my feet n electronics😀
tnx,
stefan
but how to do that will be my tomorrow´s research. huhu, i dip my feet n electronics😀
tnx,
stefan
cviller, thanx again for offering your help.
After a friend of mine also supposed that the double fet is gone, i was offensive and changed it with two 2sk 170. I matched them with a 9V battery and a 10Ohm resistor.
Than i split the source resistors (two 20 Ohms) and everything is fine now. soundstage still in the middle.
When i plugged it in there still was no sound on the left channel, but it turned out that the cable was broken. (but the channel was also😉 )
tnx
stefan
After a friend of mine also supposed that the double fet is gone, i was offensive and changed it with two 2sk 170. I matched them with a 9V battery and a 10Ohm resistor.
Than i split the source resistors (two 20 Ohms) and everything is fine now. soundstage still in the middle.
When i plugged it in there still was no sound on the left channel, but it turned out that the cable was broken. (but the channel was also😉 )
tnx
stefan
- Status
- Not open for further replies.