Ok, I am back and ready to tackle the issue of the exploding chips.
So I am not seeing any solder bridges. The polarity is correct and the voltage is about 77v when I measure between + and - terminals on PSU out.
Will start de-soldering the chips this evening unless we need them still for trouble shooting.
Thanks!
-Dan
So I am not seeing any solder bridges. The polarity is correct and the voltage is about 77v when I measure between + and - terminals on PSU out.
Will start de-soldering the chips this evening unless we need them still for trouble shooting.
Thanks!
-Dan
Attachments
OK. I think I will proceed to build the other channel using the chips from Mouser, and try it again. When I get close I will post pics as I do the check list before I even think about engaging the power. If that is successful, then will rebuild this one.
I will keep the exploded channel in tact in case someone has another thought or test they want me to run.
I appreciate all the support!!
-Dan
I will keep the exploded channel in tact in case someone has another thought or test they want me to run.
I appreciate all the support!!
-Dan
After quite a lengthy delay, I finally assembled the second channel of my Dual Mono build using the 7293 chips from Mouser. To my amazement, there were no sparks or explosions. And even more exciting is that it pumped music through my crappy test speaker.
So I proceeded to replace the exploded chips with the ones procured through mouser and suddenly that board fired up in an uneventful manner also playing music through my crappy test speaker.
I am elated! I am going to assume that the 7293 chips I had were counterfeit and did not want to work in parallel, but will not rule out that I may have damaged them while bending the pins "pinnocchio style" so the board would mount nicer.
There are some distortion noises turning on and off the amp that I am thinking will be solved through adjusting the DC trim or just by adding in some Neurochrome speaker protection on top of my soft start.
Now to build the second power supply, test it and put it all back together while engaging in holiday cheer.
Thanks again to everyone who helped out directly and indirectly, this community and the forum in general. It is incredible that you are all making this level of home audio possible for us that reside outside the 1% clubs of the world.
So I proceeded to replace the exploded chips with the ones procured through mouser and suddenly that board fired up in an uneventful manner also playing music through my crappy test speaker.
I am elated! I am going to assume that the 7293 chips I had were counterfeit and did not want to work in parallel, but will not rule out that I may have damaged them while bending the pins "pinnocchio style" so the board would mount nicer.
There are some distortion noises turning on and off the amp that I am thinking will be solved through adjusting the DC trim or just by adding in some Neurochrome speaker protection on top of my soft start.
Now to build the second power supply, test it and put it all back together while engaging in holiday cheer.
Thanks again to everyone who helped out directly and indirectly, this community and the forum in general. It is incredible that you are all making this level of home audio possible for us that reside outside the 1% clubs of the world.
Hey folks. I have been experimenting with feedback caps but I have stuck with 1000 uf. I know that smaller caps will discharge faster but how does this effect the circuit? Is there any benefit to just getting the largest cap value and leaving it at that. Does it perform better?
Subjectively speaking, has anyone compared say a 1000 uf Audio Note to a 680 uf Audio Note of the same series?
Subjectively speaking, has anyone compared say a 1000 uf Audio Note to a 680 uf Audio Note of the same series?
@Destroyer OS - do you still have any of the boards? Curious if you're planning on doing any more group buys or if you have another amp in the works?
Thanks - been enjoying following your projects (I just found out about them recently).
Allen
Thanks - been enjoying following your projects (I just found out about them recently).
Allen
Hey guys, I was given this project to build for a friend. He sent me the chassis, boards, parts, so slowly checking all the parts.
Is there any kind of wiring diagram and schematic for the power supply, amp board? I am just going by all the pictures in this thread, might be simpler if someone put this together. I am willing to help draw something up to help others, as I have 40+ years of experience repairing and building vintage tube gear.
Thanks
Dan
Is there any kind of wiring diagram and schematic for the power supply, amp board? I am just going by all the pictures in this thread, might be simpler if someone put this together. I am willing to help draw something up to help others, as I have 40+ years of experience repairing and building vintage tube gear.
Thanks
Dan