diff --git a/misc/Completely non-sketchy $20 2700V transistor breakdown tester (Emeco) - Page 1.pdf b/misc/Completely non-sketchy $20 2700V transistor breakdown tester (Emeco) - Page 1.pdf new file mode 100644 index 0000000..43c7615 Binary files /dev/null and b/misc/Completely non-sketchy $20 2700V transistor breakdown tester (Emeco) - Page 1.pdf differ diff --git a/misc/HPS10 TD V1.1.pdf b/misc/HPS10 TD V1.1.pdf new file mode 100644 index 0000000..7810b37 Binary files /dev/null and b/misc/HPS10 TD V1.1.pdf differ diff --git a/misc/IMG_20230709_151421391.jpg b/misc/IMG_20230709_151421391.jpg new file mode 100644 index 0000000..20df02c Binary files /dev/null and b/misc/IMG_20230709_151421391.jpg differ diff --git a/misc/IMG_20230803_120902004.jpg b/misc/IMG_20230803_120902004.jpg new file mode 100644 index 0000000..9aade4f Binary files /dev/null and b/misc/IMG_20230803_120902004.jpg differ diff --git a/misc/IMG_20230803_120909934_HDR.jpg b/misc/IMG_20230803_120909934_HDR.jpg new file mode 100644 index 0000000..94361b1 Binary files /dev/null and b/misc/IMG_20230803_120909934_HDR.jpg differ diff --git a/misc/MCRP 3-40.3C With Erratum z.pdf b/misc/MCRP 3-40.3C With Erratum z.pdf new file mode 100644 index 0000000..382d816 Binary files /dev/null and b/misc/MCRP 3-40.3C With Erratum z.pdf differ diff --git a/misc/VID_20230518_224914372.mp4 b/misc/VID_20230518_224914372.mp4 new file mode 100644 index 0000000..a3a2d6e Binary files /dev/null and b/misc/VID_20230518_224914372.mp4 differ diff --git a/misc/battery_powered_equipment_is_good b/misc/battery_powered_equipment_is_good new file mode 100644 index 0000000..0246126 --- /dev/null +++ b/misc/battery_powered_equipment_is_good @@ -0,0 +1,5 @@ + +simple, simple, simple +battery powered, battery powered, battery powered. +keep a watch on battery powered test equipment. +always nice to have. can wrench on the car with these. \ No newline at end of file diff --git a/misc/limit_switches_and_estop_switches b/misc/limit_switches_and_estop_switches new file mode 100644 index 0000000..838432f --- /dev/null +++ b/misc/limit_switches_and_estop_switches @@ -0,0 +1,8 @@ +limit switches, also EStop switches (emergency) should +always activate low, idle high. it must idle high, because +consider what would happen if it idles low, then the wire +gets inadvertedly disconnected. you wouldn't notice it. +BUT, you can also just put all estops on an actual hardware +disconnect for best practice. At the risk of frying some +not robust chips (tradeoff). Though the note for limit switches +remains correct. diff --git a/misc/pcb_panels_for_enclosures_and_racks b/misc/pcb_panels_for_enclosures_and_racks new file mode 100644 index 0000000..27f1ae3 --- /dev/null +++ b/misc/pcb_panels_for_enclosures_and_racks @@ -0,0 +1,19 @@ +i knew for a while about making a pcb front panel for a case. +i did this on the flammable gas sensor. however, i didn't think +that it's also practical to make a pcb front panel for custom rack +mounted hardware, like in a server rack. That is fancy. why not? + +https://www.eevblog.com/forum/projects/trying-to-make-affordable-metal-case-for-custom-pcb/msg1315739/#msg1315739 + +says that the pcbs wouldn't be able to handle the stress of holding +onto the rack at the sides. fair enough, but it should still be possible +to use metal for the sides, and then a separate front panel that is a pcb. +apparently this isn't common practice, looking at enclosures, e.g. +https://www.circuitspecialists.com/collections/rackmount-enclosures +but then jlcpcb only came about recently, so i can understand why large +front panel pcbs weren't used in the 90's or early 2000's. +Now, it would be cheap to do. +couple years ago, making this affordable only recently. + +more good ideas +https://www.eevblog.com/forum/manufacture/how-do-you-house-larger-than-average-home-projects/msg3351036/#msg3351036 \ No newline at end of file diff --git a/misc/star_grounding_vs_daisy_chain b/misc/star_grounding_vs_daisy_chain new file mode 100644 index 0000000..535b0ad --- /dev/null +++ b/misc/star_grounding_vs_daisy_chain @@ -0,0 +1,19 @@ + +"NB Never daisy-chain earth wiring: Wire all the Earths back to a +central connection (Star-grounding), which is connected to Mains +Earth - this also serves to protect you in case of an electrical +leakage / short" +This is good. I've heard about the star ground, but never heard +what not to do such as: daisy chain grounds. That is no good. One thing to +avoid. + +https://electronics.stackexchange.com/questions/643007/understanding-why-daisy-chaining-causes-ground-loops-in-this-setup + +has an explanation, though I don't really need one. + +Is there another ground type besides daisy chain / star grounding...? + +There's this but it's not well written. +https://eepower.com/technical-articles/single-point-and-multi-point-signal-grounding/ + + diff --git a/misc/ti_powersupply_topologies_book.pdf b/misc/ti_powersupply_topologies_book.pdf new file mode 100644 index 0000000..934b575 Binary files /dev/null and b/misc/ti_powersupply_topologies_book.pdf differ diff --git a/misc/ti_powersupply_topologies_book_notes b/misc/ti_powersupply_topologies_book_notes new file mode 100644 index 0000000..b68fc14 --- /dev/null +++ b/misc/ti_powersupply_topologies_book_notes @@ -0,0 +1,6 @@ +per amp hour 494 +took a quick look at it. + +doesn't have much background about the topologies +it does however have waveforms, which while being +unusual, is actually quite useful \ No newline at end of file