For those who wish to install snubbers (schematic components CX1, RS1, CS1) into this PCB, but find the mathematics and measurements of Jim Hagerman's article to be a bit daunting, may I suggest http://www.diyaudio.com/forums/powe...sformer-snubber-using-quasimodo-test-jig.html. You attach this little jig to your transformer, connect up an oscilloscope, and 3 minutes later you've got an optimum (criticaly damped, zeta=1.0) snubber, without ever picking up a calculator or launching a spreadsheet.
Since the optimum component values of this type of snubber depend upon the power transormer and nothing else, we can make a table of transformers and their optimized snubbers, so that folks don't need to reinvent the wheel. To show an example, I will provide one entry for this table:
Transformer: Avel Lindberg Y236602
type: toroid, dual primary (115/115), dual secondary (35/35)
size: 230 VA
configuration used here: primaries parallel (115V), secondaries series (70V)
application: Akitika GT-101 power amp
Optimized CX: 10 nF (0.01 uF)
Optimized CS: 150 nF (0.15 uF)
Optimized RS: 110 ohms
(Here's a link to the thread about AL toroid snubber)
Since the optimum component values of this type of snubber depend upon the power transormer and nothing else, we can make a table of transformers and their optimized snubbers, so that folks don't need to reinvent the wheel. To show an example, I will provide one entry for this table:
Transformer: Avel Lindberg Y236602
type: toroid, dual primary (115/115), dual secondary (35/35)
size: 230 VA
configuration used here: primaries parallel (115V), secondaries series (70V)
application: Akitika GT-101 power amp
Optimized CX: 10 nF (0.01 uF)
Optimized CS: 150 nF (0.15 uF)
Optimized RS: 110 ohms
(Here's a link to the thread about AL toroid snubber)
Cs - fits 2.5mm or 5mm lead spacing caps
Cx - fits 5mm or 7mm lead spacing caps
C17/18 - fits 5mm lead spacing caps
I need some help soldering these big pads - can anyone point me to something that might help me get the hang of it? First time I have ever soldered these big 3w resistors and I can't get a clean joint. Using Cardas quad eutectic solder and iron set at 300 C. Do I need to heat these pads for a *serious* amount of time?
size matters
You'll need a big chisel tip, maybe 3mm. The tiny ones don't carry the heat.
After a while you'll get used to bigger tips and higher heat. Now I am loath to shift gears down to the little stuff. Some say it is safer for your components to use higher heat for shorter durations; sort of searing the tips instead of toasting the whole component.
You'll need a big chisel tip, maybe 3mm. The tiny ones don't carry the heat.
After a while you'll get used to bigger tips and higher heat. Now I am loath to shift gears down to the little stuff. Some say it is safer for your components to use higher heat for shorter durations; sort of searing the tips instead of toasting the whole component.