What We've All Been Waiting For--700 BP boards!!!!!!!!!

Gepetto said:
Appearance has to be part of the overall design. Even though it is inside the chassis, it will bug me to know that it isn't right :-)
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This is when you know someone loves what they are doing and not just rushing through to the final product. The Mona Lisa would not have been quite as appealing if her nose was crooked
 
Gepetto said:
Seems to have stopped today Lee. Gotta run the snow blower again.

Couple of nice days and then they are predicting more...
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How much ya got?? Got a 3/4 ton Dodge 4WD with a chip to get you around in this??
 
Thankfully, we only got about another 4" but as Joe said, Tuesday they are expecting more. At least later in the week it get's into the 40s-50s. Though not the worst Winter we have had, this one has been tedious
 
LMOAO!! A Mini-Cooper??? I looked inside one of those things and my immediate thought was it would take the fire department and the "Jaws of Life" to get me out!
 
And evidently you fit in it?? Wasn't knocking the choice Joe, as I'm the only one here who smiles when they pull up to the pump I can appreciate the mileage that little cutie gets. Being tall does have it's disadvantages. I really enjoyed the Triumph Herald I had in High School but didn't take long to outgrow it. Not to mention sex was impossible unless the top was down...
 
laatsch55 said:
And evidently you fit in it?? Wasn't knocking the choice Joe, as I'm the only one here who smiles when they pull up to the pump I can appreciate the mileage that little cutie gets. Being tall does have it's disadvantages. I really enjoyed the Triumph Herald I had in High School but didn't take long to outgrow it. Not to mention sex was impossible unless the top was down...
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Yeah I am 5'11" Lee so I fit. It actually has more room than it looks inside, most people that ride with me are amazed at the inner room. I get about 40MPG, but it takes premium gas so some of those savings go back.

I only drive cars with manual transmissions so the choices are getting fewer and fewer these days. Driving a manual is becoming a lost art like many other things. My daughter drives a 6 speed Acura but the guys she dates only know how to drive automatics :-)

Part of the wussification of American men.
 
She's also fixin to carry a handgun so perhaps she can come to their aid when getting car-jacked..My daughter learned to drive a 5 speed Toyota pickup on some lonely Campbell County road when she was 8 years old. A phone book and my briefcase was required for her to see, and she's a heck of a shot with her 1911 .45.
 
laatsch55 said:
She's also fixin to carry a handgun so perhaps she can come to their aid when getting car-jacked..My daughter learned to drive a 5 speed Toyota pickup on some lonely Campbell County road when she was 8 years old. A phone book and my briefcase was required for her to see, and she's a heck of a shot with her 1911 .45.
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OK now... back on topic (at least for a second)

AC wiring in
Output wiring in
Light Board wiring in
All laced up

Ready for shorts check and installation of pre-tested control board

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Gepetto said:
OK now... back on topic (at least for a second)

AC wiring in
Output wiring in
Light Board wiring in
All laced up

Ready for shorts check and installation of pre-tested control board

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AC wiring disappears on top of the topmost bulk cap and then makes a 90 degree turn south and then turns again to come up right into the sidewall mounted terminal block. It is important to always have an AC wire paired with one carrying current in the opposite direction. This wiring scheme accomplishes this. The original AC wiring scheme that Phase Linear employed did not adhere to this tenet. It is also important to keep AC as far away from all other wiring. If AC has to cross other wires, do it with as much separation as possible and do the cross at right angles.
 
Initial smoke check went fine...

All AC and DC voltages checked out as they should.

Next the control board in place and a set of pre-drivers.
 
Power went out last night about 10:00PM. Gotta go to the field here in a bit, but I'll be back early. Looks like we'll be testing within 12 hours of each other anyway...
 
Joe, how did you determine what value the 33uf/160v should be?
 
laatsch55 said:
Joe, how did you determine what value the 33uf/160v should be?
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The value is non critical Lee, it is just a power bypass cap. The combination of the 33uF electrolytic and the 0.33uF polypropylene provides broadband frequency coverage from low to high frequencies.

The voltage rating is critical, needs to be >20% above the rail voltage of 105V for proper derating. After that I picked the largest value that I had space for on the board.

None of the Phase Linears have this so this is an improvement.

That explanation help?
 
Well of course I even understand most of it!! Now, about that diode....
 
laatsch55 said:
Well of course I even understand most of it!! Now, about that diode....
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The diode is for FMEA Lee. So many occurrences of bad Q6, open Q6, broken wire to Q6 etc. said why not put a fail safe measure in place that limits bias current in the presence of a Q6 failure. If Q6 fails short, so what, you have more crossover distortion but no catastrophic failure mode. If Q6 fails open, you lose control (by Q5) of the upper side transistors, they are pulled up to the B+ rail by R17 and R18 while Q5 is still trying to regulate the output by pulling on the lower side transistors. What ends up happening is a very large bias current results and damage occurs.

The purpose of this zener diode is to be there as a safety net in the event of a Q6 failure mode. It limits at a bias current above the normal set point but the goal is to get this diode shunt voltage dialed in to protect at a reasonable level to prevent damage. In normal operation, this diode is effectively doing nothing by intent.
 
I thought it was a Q6 protector, thanks Joe, very nifty of ya there guy, it just keeps getting better and better, my hat's off to you Sir!!
 
When Q6 fails open then Q5 bites the dust followed quickly by one of the 1304,05 pairs?? and D9,D10?
 
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