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)
If I'm looking at the board normally (I can read whats written) R5 is placed sideways. Thats why I mean left and right.
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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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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