Blue Hawaii schematics in Eagle, can somebody check please?
Jul 16, 2004 at 3:00 PM Thread Starter Post #1 of 20

Glassman

Headphoneus Supremus
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right now I'm working on Blue Hawaii, starting with the amp board schematics..

here you can find schematics posted by Dr. G himself, hope it's correct.. and here is my redraw in Eagle..

btw. why is justin using two more A1968 in the current sources than what's in the schematics
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Jul 16, 2004 at 3:14 PM Post #2 of 20
wow, this looks quite different? how can this be??
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Jul 16, 2004 at 3:30 PM Post #3 of 20
Full headwize writeup with lots of pictures soon...

quote
btw. why is justin using two more A1968 in the current sources than what's in the schematics

actually 1 more per side. one is the driver transistor. so one
driver and 6 outputs per tube makes for 14 transistors. The 15th is
the -300 volt driver transistor. 2sc3675. The 400 ohm resistors
are now 500 ohms.

If you absolutely have to due to parts availibility you can substitute
2sa1967's for the 2sa1968's. 2sa1968's with thermal washers definitely
recommended.
 
Jul 16, 2004 at 3:49 PM Post #4 of 20
my A1968 are on the way, I probably ordered 12pcs per board, not 14.. guess I did right..
 
Jul 17, 2004 at 2:03 PM Post #5 of 20
schematics updated, added 33pF and 100pF caps where they belong.. same address..
 
Jul 17, 2004 at 2:30 PM Post #6 of 20
The schematic is now fully correct except
add one more current source transistor per side and change
the 400 ohm resistors to 500.
 
Jul 17, 2004 at 3:15 PM Post #7 of 20
unfortunately, no way for me to get those four extra transistors, so at least I will use 430R instead of 400R.. five of them make parallel combination of ~86R, six parallel 500R make 83R and four parallel 400R make 80R.. hope it will run just fine without any overheating..
 
Jul 17, 2004 at 5:21 PM Post #8 of 20
trying to lay out the board, you can see how the chassis will look like and how big it will be.. side panels are extruded aluminium heatsinks..

look here.. this is gonna be fun
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Jul 24, 2004 at 11:09 AM Post #10 of 20
the one showed here is more recent version, I've been in touch with Kevin regarding that..
 
Jul 30, 2004 at 5:18 AM Post #12 of 20
it's there, IT'S THERE!

thanks GO.. ehm Kevin
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Jul 30, 2004 at 6:44 AM Post #13 of 20
Jul 31, 2004 at 9:00 AM Post #15 of 20
there's 300dpi layout exported from the .pdf, I have 3 layer Paint Shop Pro file if anyone interested, let me know..
 

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