Tell us about yourself!
haiboth the lm317 ( positive voltage ) and lm337 ( negative voltage ) are 1 amp devices - run a few op-amps from ."Found" the transformer - so kids had played with something like a tv - used a pair of analogue meters - to get dual supply - not brillient but its worked for 30 years . The box was from a dump . If your willing to get things working that do not look brillient - can do a lot with not very much
Made my version with lm317 and the lm337 - found the transformer - looked to be part of tv - it worked . As ebay paypal international shipping not then - used some analoge meters . Dig metering not then available - all such equiopment expensive . After 30 years it still works . Repurposed bits - brings cost down if appearance sacrificed
Paper Mache Class
Laser Cutting Class
Welcome to Laser Cutting
hai - yes there is - major requirement steady hand and patience abrade the pcb copper , cover with masking tape - ( press down hard - to exclude air ) draw circuit cut out the parts so that the copper track shows through , paint with enamel based ( car touch up ideal ) - let "dry" - edge around with small sharp knife - take off remaining masking tape The etchant I used was Ferric Chloride - with drop of meth spirit DRILL HOLES FIRST
Amazing 3D Projection Pyramid in 10 min from Clear Plastic Sheet !
haiSimply because a company media / press release dept - nothing against arts - but of arts people where they SAY its holographic as its that nice nice buzz word - and company with management want the advance position Dennis Gabor - not even difficult to look it up - google holography - close enough where GB patent . MIT HAVE DONE YEARS OF RESEARCH - Had that question in Crown Court (1990 ) - the device - they wanted a holographic system - which it was not - but did not state that there was not a holographic system ""around"" ( being investigated ) Media people really should check the facts - as all scientists / engineers / mathematics required to do
Arduino and MAX7219 - 50 Volt - Digital Volt Meter
haifollowing suggest a transformer circuit - battery is better - COMPLETLY ISOLATED For 230 v - which ""played with"" - and got a few belts from - the use of a MAX 138 / 139 / 140 - which built as well ( sadly the days of "samples" long gone , but one can at least reward by good reference )Its 3.5 digits of device - depends how accurate it required as the article has eight digits - and ain't gonna get no-where near microvolts As an article which authour enjoyed fair enough Old adage An engineer does for £1 what any damn fool can do for £5 How many DVM with eight digits
without checking the texts - looks like colpitts oscillator thus LED with 50% duty cycle , and back emf in inductor - feeds back to the capacitor