#Fake operational transconductance amplifiers I bought on #EBay over 6 years ago. Date code doesn't make sense given that Intersil discontinued the #CA3080 over a decade ago. The real chip should have a diode across pins 4 and 5. Only one chip seems to have it -- but it is reversed. The rest have resistors between pins 1 and 4, and between 4 and 5, consistent with an op amp that provides offset null pins. Pin 8 also seems to be connected. Both 1 and 8 should be NC. #electronics#opamp
At least the single rail #opamp#oscillator circuit works with these counterfeit chips. Maybe I'll turn them all into #LED blinkies and Schmitt triggers.
LED lightbulb autopsy. All the LED chips are cracked. The lamp still flickered and sometimes worked steadily and they were not getting hot from use, merely slightly warm.
All the cracks start from where the chips have been soldered, so I think the cracking might've been caused by being soldered too hot/too long.
Bien que l’œil soit en grande partie protégé des effets délétères de la lumière par des systèmes antioxydants complexes et puissants, une exposition excessive peut induire des lésions tissulaires irréversibles. Par exemple, une surexposition à la lumière du soleil accélère l’apparition et la progression de la dégénérescence maculaire liée à l’âge (DMLA). À ce risque s’ajoutent ceux associés à l’usage des lumières artificielles, de jour comme de nuit. Il est en particulier établi que la lumière bleue, émise notamment par les LED, endommage les cellules de la rétine et entraîne des troubles du sommeil et d’autres anomalies associées à une dérégulation du rythme circadien.
We are printing educational nad agitprop materials for #Queer, #anarchist, #climate and #antifascist#activist groups, who cannot afford (or have their content rejected from) commercial capitalist printshops.
At the moment we have around 500 EUR saved for this purchase and we hope you can either help us through matching donation (liberapay.com/tepewu/), so we can buy a printer (realistic 2nd hand price in Poland is ~800-1000 EUR) or you have one and would sell it to us at a discount.
mitxela has built an #LED matrix earring from 52 0201(!) LEDs (i.e. 0.65 × 0.35 mm footprint) on a 9 mm diameter circular PCB. Or rather, two PCBs soldered back-to-back because this density of components basically requires a four-layer PCB with blind and/or buried vias, which would've been very expensive. The video also features a "very cheap" (3600 USD) pick & place machine. I expect these to show up in makerspaces soon.