Hello.
I am new here. I joined because I have a 'little' problem with my Zen v9. I have made Zen v4 and it sounds well but I found LU1014 and I wanted to do v9. I know it's an old contruction but it should sound much better. I made PCB according to fig.8 of this article Zen Variations 9 | Pass DIY but I can't set any current by setting P1.
I don't understand a way of control Q1. I have 44V instead of about 23V on a drain of Q2. It means there is no current. I can set 3V on drain of Q1 but there is still no current. Q1 is stuck. But it's connected to ground by R17+R7. Lu1014 is a N-channel transistor so it is switched off by grounding. I made a test schema according to fig 10 and if its gate was connected to ground Q1 didn't conduct. It conducted only if I got + to gate.
So if you were so pleasant and patient please explain it to me.
I am new here. I joined because I have a 'little' problem with my Zen v9. I have made Zen v4 and it sounds well but I found LU1014 and I wanted to do v9. I know it's an old contruction but it should sound much better. I made PCB according to fig.8 of this article Zen Variations 9 | Pass DIY but I can't set any current by setting P1.
I don't understand a way of control Q1. I have 44V instead of about 23V on a drain of Q2. It means there is no current. I can set 3V on drain of Q1 but there is still no current. Q1 is stuck. But it's connected to ground by R17+R7. Lu1014 is a N-channel transistor so it is switched off by grounding. I made a test schema according to fig 10 and if its gate was connected to ground Q1 didn't conduct. It conducted only if I got + to gate.
So if you were so pleasant and patient please explain it to me.
LU1014 is JFet , normally on part , so you need negative at gate to shut it off
you probably have fake one , if you need positive voltage at gate to conduct
if you did something , and it doesn't conduct with article - problem is at your side - either dud part or implementation
you probably have fake one , if you need positive voltage at gate to conduct
if you did something , and it doesn't conduct with article - problem is at your side - either dud part or implementation
Lu1014 is a depletion mode FET............. Lu1014 is a N-channel transistor so it is switched off by grounding.
Depletion and enhancement modes - Wikipedia
you are describing an Enhancement mode FET.I made a test schema according to fig 10 and if its gate was connected to ground Q1 didn't conduct. It conducted only if I got + to gate.
So if you were so pleasant and patient please explain it to me.
Looks like you have bought fakes or you are not testing them correctly.
Vertical mosFETs are available very cheaply. All the cheap ones are enhancement mode. These are what get used to make fakes of the more expensive Laterals and jFETs.
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Thank you for your fast reply.
I suppose they are fake (China). I checked PCB twice and I found a mistake before. C1 capacitor was mounted inversely and it conducted. Then I was able to set the current because I give + to gate of Q1. But R7 resistor was burning.
Where can I buy real LU1014.
I suppose they are fake (China). I checked PCB twice and I found a mistake before. C1 capacitor was mounted inversely and it conducted. Then I was able to set the current because I give + to gate of Q1. But R7 resistor was burning.
Where can I buy real LU1014.
It sounds great but there is IF. Anyway thank you for it.If someone with a U.S. address wants to organize distribution...
All of you helped me a lot. I didn't realize that quite cheap elements and not so common might be fake.
Now if you are in a hurry and don't mind spending a few $ Deepsurplus still has
a few. And they are indeed real. He bought a lot of them when the suplier went
bankrupt. And the few I bought from them test out good!
http://www.deepsurplus.com/Electronic-Components/LU1014D-JFET?range=49,51,51
a few. And they are indeed real. He bought a lot of them when the suplier went
bankrupt. And the few I bought from them test out good!
http://www.deepsurplus.com/Electronic-Components/LU1014D-JFET?range=49,51,51
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