March 9, 201016 yr comment_333336 So far, 2 silk screen errors. Total. Plus the holes on the 3381's a bit tiny. Plus one zener hole a bit tiny. Pretty fucking good for a project of this magnitude. I challenge anyone to do a project of this scope and get it 99.99999999% right the first time. Absol-bloody-lutely! Stunningly great piece of work Kevin. I've never done PCB design anything like this large or complex, and I've always had a greater mistake density. Didn't mean to come across as a knit-picker Report
March 9, 201016 yr comment_333349 Kevin, If those are SumR transformers double check the secondaries by hand. On the last trafo he made for me (for the BHse) he mis-marked the center tap on one of the secondaries, which thankfully didn't cook anything. I always test the AC out of all transformers first. And unloaded power draw checking for shorted turns. In fact i also check every semiconductor (especially the led's) and measure the resistors. Saves a lot of time later. Report
March 9, 201016 yr Author comment_333356 Checking every component is well worth it (especially the leds since they are a pain to remove later on). Thanks for the warning Nate, the CT on my KGSS transformer was in the wrong spot or I just misunderstood the SumR specsheet. Report
March 9, 201016 yr comment_333361 I'm glad that I'm not the only sod who checks every resistor Report
March 9, 201016 yr comment_333364 Checking every component is well worth it (especially the leds since they are a pain to remove later on). Thanks for the warning Nate, the CT on my KGSS transformer was in the wrong spot or I just misunderstood the SumR specsheet. That's exactly what happened on mine, the CT was marked wrong. Thankfully it was a low-voltage mistake but I'm not happy to hear it's happened more than once. Report
March 9, 201016 yr comment_333365 The 534-1847 are the wrong size, I will have to measure again... Should be 534-3487... So .5 instead of .625 (actual is .55 which is .5 with a .05 spacer) I ordered .375 anyway ?? Report
March 12, 201016 yr comment_334563 http://gilmore.chem.northwestern.edu/t2chassis29.jpg Soooo close... 1 more resistor value on backorder wire stax jacks Will finish wiring the power supply tomorrow. Few more screws, nuts and bolts... Report
March 12, 201016 yr comment_334580 http://gilmore.chem.northwestern.edu/t2chassis29.jpg Soooo close... 1 more resistor value on backorder wire stax jacks Will finish wiring the power supply tomorrow. Few more screws, nuts and bolts... Wow, nice gold Mabuchi motor on the board! Report
March 13, 201016 yr comment_334596 Wow, nice gold Mabuchi motor on the board! I was not aware that mabuchi made motors this expensive Report
March 13, 201016 yr comment_334659 another correction to the bom the spacers (.5 inch and 2 inch) are supposed to be 4-40 not 6-32 Report
March 13, 201016 yr comment_334708 updated amplifier schematic http://gilmore.chem.northwestern.edu/t2schem.pdf Report
March 13, 201016 yr comment_334709 I can't believe that 4 330k resistors are getting in the way of this thing making music. Looks great though and thanks for all the documentation Kevin. Report
March 13, 201016 yr comment_334737 I can't believe that 4 330k resistors are getting in the way of this thing making music. Patience grasshopper. It will make music soon. Very soon. Have to finish power supply first. Worked on it 3 hours today and 2 hours tomorrow should finish it. Had to go to tristate electronics for the right size spacers. Ordered the rest of the parts including xlr connectors to make cables with which to hook it up to a source, plus the right sized spacers for the amp board. No reason to rush this, it will be done in plenty of time for CJ010. I want it perfect the first time it powers on. Report
March 14, 201016 yr comment_334902 http://gilmore.chem.northwestern.edu/t2power3.jpg Got to find better 1/4-20 bolts. 2 of them have cracked off at the screw head. Report
March 14, 201016 yr comment_334908 That is so flippin' nice! I can hardly wait to hear what you have to say about how it sounds. Just awesome! Report
March 14, 201016 yr comment_334912 Patience grasshopper. My impatience certainly wasn't with you Kevin, I perhaps mistakenly thought that those resistors were out of stock and it seemed like a pisser that the amp would have to wait for them. Report
March 14, 201016 yr comment_334945 The resistors ARE on backorder. But they are not really important as they are the input filter. Too bad i did not wire the stax jacks, I would have something to listen to already ATOMIC BATTERIES TO POWER TURBINES TO SPEED PHASERS ON STUN http://gilmore.chem.northwestern.edu/t2amplifier1.jpg all voltages look good... Filament transformer is a slight bit high... The output tubes are 6.5 vac the input tubes are at 6.7 vac. Don't trust my 30 year old meter, so i'll bring home something recent and calibrated before i re-spec the filament transformer. Report
March 14, 201016 yr comment_334956 stunning. Congratulations for such a nice built. I hope you can listen to it soon Report
March 14, 201016 yr comment_334965 Epic! Did you have to take the tranquilizers before firing it up? Report
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