Hello Wellerman,
I was just about to post this info on the other thread. I was getting no output and i soldered the jumper on R15. I went from no output to a low hum with a low high pitch noise. I have gone back and cleaned some sloppy soldering. Yet Im still getting the 5v on Q3. Im also getting 5v on Q6-Q9 top and .075v on the bottom. Ive tested continuity on all diodes and everything seems fine. What else do you suggest should i check?
-Thanks so much!
I was just about to post this info on the other thread. I was getting no output and i soldered the jumper on R15. I went from no output to a low hum with a low high pitch noise. I have gone back and cleaned some sloppy soldering. Yet Im still getting the 5v on Q3. Im also getting 5v on Q6-Q9 top and .075v on the bottom. Ive tested continuity on all diodes and everything seems fine. What else do you suggest should i check?
-Thanks so much!
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To get voltages around Q3 in the direction of desired values, change R21-24 from 10R to 20R like I did. Your voltages at the bottom of Q6-9 are even higher than what I had at first (around 68mV, you have 75mV). You may also have to lower R10 a bit (to 8k2 or 6k8) to get Vc > Vb > Ve around Q3.
But I doubt if that is the main problem if no music comes through. Could be some faulty components. The ZVP3310 is prone to failure, I had a bad one myself (but even then music came through if only swamped by quite a bit of noise)
But I doubt if that is the main problem if no music comes through. Could be some faulty components. The ZVP3310 is prone to failure, I had a bad one myself (but even then music came through if only swamped by quite a bit of noise)
In your measurements, what do you mean by R5 left and right? Left and right channel? I wondered about the 3V difference. If you mean top and bottom, then it's ok.
If I'm looking at the board normally (I can read whats written) R5 is placed sideways. Thats why I mean left and right.
OK. Bottom of Q2 cannot be 23V. Must be 0V. I would try replacing Q2. Be careful, it is sensitive to ESD.
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By the way just measured the same bottom pin of Q2 on my second board and Im also getting -23v. May be I've installed it backwards? I followed the drawing on the board and did not verify what is the board expecting and what the component provides...
Also maybe I'm installing it wrong. How should I go about soldering it with out screwing it up? Im just treating it like any other component...
Also maybe I'm installing it wrong. How should I go about soldering it with out screwing it up? Im just treating it like any other component...
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Maybe. Check the datasheet for pin layout (easily found online). In the picture it looks like you've got it right. I'm off to bed now. Good luck!
No go, I tried another unit and got the same -23v reading and if i flipped it the output would go to positive 23v but I still did not hear anything on the RCA out but hum.
Quick question whats the SET P1 FOR ZERO VOLTS DC hole for? Or better yet if there is supposed to be 0 in Q11 how should I use this pin hole?
Ive got great news. The ZVP3310 where bad i was killing it with my fingers. Installed new one with out touching it with my fingers and now i have .0009v at P1.
I installed 4 19.7 ohms on R21-24 and a 6K75 resistor on R10. My current readings are as follow.
Q3 Top:7.38v, Middle:7.37v, Bottom:6.7v
Q6 Top:6.71v, Middle:0, Bottom:0.121v
Q7 Top:6.71v, Middle:0, Bottom:0.121v
Q8 Top:6.71v, Middle:0, Bottom:0.122v
Q9 Top:6.71v, Middle:0, Bottom:0.121v
Q2 is so sensitive i don't even want to look at it...
Music IS coming through but its not clean. Ive got a high pitch noise that comes and goes.
Whats the next step?
Man I feel good! Thing is finally coming alive...
I installed 4 19.7 ohms on R21-24 and a 6K75 resistor on R10. My current readings are as follow.
Q3 Top:7.38v, Middle:7.37v, Bottom:6.7v
Q6 Top:6.71v, Middle:0, Bottom:0.121v
Q7 Top:6.71v, Middle:0, Bottom:0.121v
Q8 Top:6.71v, Middle:0, Bottom:0.122v
Q9 Top:6.71v, Middle:0, Bottom:0.121v
Q2 is so sensitive i don't even want to look at it...
Music IS coming through but its not clean. Ive got a high pitch noise that comes and goes.
Whats the next step?
Man I feel good! Thing is finally coming alive...
You've got powerful fingers 🙂
The high-pitched noise might be oscillation. I have no experience with that. Have you grounded the board well?
Maybe I would put it in its enclosure, use wiring/grounding scheme as intended in the final product and see if the noise goes. If not, come back for more advice.
The high-pitched noise might be oscillation. I have no experience with that. Have you grounded the board well?
Maybe I would put it in its enclosure, use wiring/grounding scheme as intended in the final product and see if the noise goes. If not, come back for more advice.
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It has improved a lot. Yet I'm getting a lot of hum. When i turn it on by its self I have hum and when I turn on the turntable hum doubles.
The sound its really clear and the stereo field is great.
Just the hum noise... How can I get red of this?
-Thanks!
The sound its really clear and the stereo field is great.
Just the hum noise... How can I get red of this?
-Thanks!
Still no C7 installed in your board? That would be good, as that component caused oscillation in other peoples Pearl.
Another question: I see no heat sink on your 7824 and 7924. Aren't they getting hot? At 36V input, the 7824 might be dissipating something like 0.5W.
Another question: I see no heat sink on your 7824 and 7924. Aren't they getting hot? At 36V input, the 7824 might be dissipating something like 0.5W.
Did not install C7. 7824/7924 not getting hot at all. But temp is cool in my room.
One thing, the turntable ground cable is connected to my old amp (Rega) not to the Pearl 2. That a problem?
One thing, the turntable ground cable is connected to my old amp (Rega) not to the Pearl 2. That a problem?