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Since I can't really send attachments though PM's so I'll leave the schematic I was using (the schematic and the boardlayout is linked, changes that happen to the schematic happen on the board). I'll make a later identical layout with values, unless someone else would like to.
Currently, the board layout doesn't have any traces, I hid all the lines that had gone to 0V or V+/V-. I need to adjust the layout of the PS section before I do any routing.
Currently, the board layout doesn't have any traces, I hid all the lines that had gone to 0V or V+/V-. I need to adjust the layout of the PS section before I do any routing.
I think this should be a small milestone, Just need to rename a bunch of parts, tweak one or two traces and create a professional looking schematic, could anyone recommend a nice program for creating nice looking schematics?
I feel like I've finally accomplished something significant
I'd like to know if anyone would be interested in distributing? or who might be able to organize the GB.
I feel like I've finally accomplished something significant
I'd like to know if anyone would be interested in distributing? or who might be able to organize the GB.
Attachments
P-A,
Why do you avoid angles less than 90 degrees? Would 45 degrees be OK? My boards use lots of small angles, and curves, too, am I doing it all wrong?
BTW, I'd argue with your 'yellow electrons'. It actually depends how fast they are going, they change color due to Doppler shift. Observing their color is tricky however; concentrate hard, and you become very uncertain. Treat them casually, and they can strike your eye, causing serious damage. Have you any color electrographs? (no cloud chamber trails, please.)
Ciao,
Hugh
Why do you avoid angles less than 90 degrees? Would 45 degrees be OK? My boards use lots of small angles, and curves, too, am I doing it all wrong?
BTW, I'd argue with your 'yellow electrons'. It actually depends how fast they are going, they change color due to Doppler shift. Observing their color is tricky however; concentrate hard, and you become very uncertain. Treat them casually, and they can strike your eye, causing serious damage. Have you any color electrographs? (no cloud chamber trails, please.)
Ciao,
Hugh
I also once saw some pictures, I think it had to do with early capacitors involving glass jars and plates. Anyway the pictures showed the radiation that eminates from the plates, and it was particularly concentrated around edges and the sharp corners, not so much over the flat surface area though....
I believe I can remove the ground plane underneath the heat sinks...
Does anyone know how much Q3 and Q4 dissipate?
Any part ending with a V is a optional component for people who want to use a virtual ground and a duel rail powersupply, The correct LED's are there, check post #1085... That's the current schematic I'm using (which is linked to the board layout)
A couple more things that I should note, the headphone out for both channels is paired with a test point, they should not be used for headphone ground. The main star ground via should be used if a TRS style jack is used. This should allow me to make the ground wires a little less messy.
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This is the schematic that will be used for a building aid... Just needs a little added ownership
and the BOM is almost done, just needs some more parts and final touches.
Kurt,
Please excuse my breaking in to your post!!
R3 would be 820R and a 500R pot in series.... this permits trimming the output offset to zero, very, very important for a headphone amp.
Hugh
and the BOM is almost done, just needs some more parts and final touches.
Kurt,
Please excuse my breaking in to your post!!
R3 would be 820R and a 500R pot in series.... this permits trimming the output offset to zero, very, very important for a headphone amp.
Hugh
Attachments
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Oh, that scared me! I didn't write that! 
Ok, I'll make the changes to the board layout and schematic, a DC trim is pretty significant...
Current state of BOM:
https://spreadsheets.google.com/ccc...hMlNwbWhFMDg2RlE&hl=en&authkey=CKH76_oB#gid=0
Ok, I'll make the changes to the board layout and schematic, a DC trim is pretty significant...
Current state of BOM:
https://spreadsheets.google.com/ccc...hMlNwbWhFMDg2RlE&hl=en&authkey=CKH76_oB#gid=0
One important thing is forgotten. The output should have a 120 ohm resistor in series. This will create the standard output impedance eventhough I prefer to be able to short this resistor. You can check out my QRV09 design for inspiration.
The gain is nearly 20 dB which is too much in many cases. The design should be tested for gains down to 6 dB.
The gain is nearly 20 dB which is too much in many cases. The design should be tested for gains down to 6 dB.
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