so about :: i've made (now a total) 3 circuits that use active pre-load - all have failed due a different reasons
(i) using ~250V electrolytic capacitors in series with incandescent lamps -- the ´lytes exploded !!! (trivia) -- however it took them 1.5d (some 36h) to heat up -- later i just added more incandescents to fill the voltage gap
(ii) using ceramic capacitor before Russian Lim.?700V full-bridge . . . that actually has a std. leak - e.g. if [+][–] terminals are not connected the –[L]] –– [[~] Bridge [~]] –– [[]Load[]]––2 [[N] – connection provides enough AC for 25W incandescent as a Load to glow near it´s max brightness !!! --- everything worked correctly at nominal !!average!! values (measured by analog multimeter) but the LED and 1BJT failed after 1.5y (apx.13000h) ???
(iii) using 15nF as "200kΩ" pre-load to 60V neon lamp caused the neon´ to relatively fast dim down and collect eighter C or metal film to it´s inner surface causing more dimming (service apx.1500 + ? h) . . .
. . . so i replaced it with this ::
( it´d make sense to set at least 1 fuse close to [L] or (2-nd near [N]) terminal -- this circuit relies on 10A line protection -- i can't predict how warm the (250mW) 100 ohm limit´ll get in continuous op. and what results if it does heat up . . . ) Update/About -- (so far it does not give out any smoke) but one LED is brighter the other one -- is either the asymmetry of DB3 , a bad selection of capacitor values/ratios -- or a combination of both (some of it can be adjusted by discharge resistors , charge storage cap.-s) . . .
((the Blogger* didn´t crash so far !!! . . .))
[EoF]
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