"LM301" test 2

Offset test ::
(was even "passed" to my surprise ? ** is a good Op Amp after all)

However since it's frequency capabilities set it more to audio range - a random internet bootstrapped Op Amp circuit test ::
((this is actually a good - better than expected - result . . . again! **))

---

[Eop]

theoretical wall ~AC line detector

since there is reason to believe the ®´s j-fet input stage rather attenuates than amplifies
the E - field variations i set up a simple band-pass based 1 ::

  

this might still require extra input stage (for deep buried wires)

+ experiment with the layout , sensor , 3-sholds´ sensitivities before we can say if it´s for any good

updated an old Sq.-wave oscillator to a voltage controlled one -
to be mixed with prev. ~50Hz output ::

 

it is good to pre-test and choose + adj. the optos to the same transfer ratio ,

everything else shouldn´t be too much trouble ?

[Eop]

alternate for gas discharge indicator

((fuck this blogger *editor is slow 2day . . . ))

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]

Couple of OpAmp experiments

FF(fixed frequency design) apx.~50Hz 3-ph ((another) alternate (for a)) Sine generator

V2F experiment (poor -- attempting to grasp some principles)

[EoP]

DB3 tester (practical)

updated my Spice DB3 alternate . . .

. . . the fuzzy thing is -- i donno why it works -- Link to ◄◄ use at your own risk
[EoP]