On 02/03/2011 10:45 PM, Dainiushas wrote:
> tu daryk, daryk su diodais. Ir nepamiršk ramybės srovę pamatuot!
>

beje, ar tu pats skaitei sita:

"Crossover Distortion Summary

Then to summarise, Crossover Distortion occurs in Class B amplifiers 
because the amplifier is biased at its cut-off point. This then results 
in BOTH transistors being switched "OFF" at the same instant in time as 
the waveform crosses the zero axis. By applying a small base bias 
voltage either by using a resistive potential divider circuit or diode 
biasing this crossover distortion can be greatly reduced or even 
eliminated completely by bringing the transistors to the point of being 
just switched "ON". The application of a biasing voltage produces 
another type or class of amplifier circuit commonly called a Class AB 
Amplifier. Then the difference between a pure Class B amplifier and an 
improved Class AB amplifier is in the biasing level applied to the 
output transistors. One major advantage of using diodes over resistors 
is that the pn-junctions compensate for variations in the temperature of 
the transistors. Therefore, we can say the a Class AB amplifier is a 
Class B amplifier with "Bias" and we can summarise as:

     * Class A Amplifiers have no Crossover Distortion as they are 
biased in the centre of the load line.
     *
     * Class B Amplifiers have large amounts of Crossover Distortion due 
to biasing at the cut-off point.
     *
     * Class AB Amplifiers may have some Crossover Distortion if the 
biasing level is too low.
"

nzn kodel multisimas taip smarkiai pakeite rezultatus, nes teoriskai 
neturejo niekas pasikeisti. diodai tik temperaturini kompensavima 
suteikia. ir juodu ant balto tavo paciam duotam linke raso, kad galima 
daryti bias'inima ir su varziniu dalikliu, is ko tu labai jau garsiai 
issipyzdavojai.
o summary tik patvirtina tai, ka as tau bandau iradyti:
visi buitiniai AB stipriakai atsukus kazkiek garso pradeda groti B 
klasej, nes daugumos bias voltage primazinta iki minimalios, taupant.
dar skirtingai nuo taves, as be multisimo ir realiai esu mataves, beto, 
ne atskirai galini laipsni. rezultatai tie patys. nu bet tau gi neirodysi.


>
> On 02/03/2011 10:40 PM, CodeC wrote:
>> On 02/03/2011 10:33 PM, Dainiushas wrote:
>>> čią tą schemą pats sugalvojai? Tikrai tikrai ten viskas gerai joje?
>>
>> apart dideliu signalo nuostoliu - viskas. dariau special for you, kad
>> pamatytum tranzu poros nevienodumus. jei tu galvoji, kad bias'inimas su
>> diodais kanors keicia, tai tuoj as tuo irodysiu kad ne :) ale ant kiek
>> tu atkaklus nesamones irodinet. nekalbant kad pats neisigilini net i
>> tai, ka pats man nuorodose dalini.
>> siaip va kol as darysiu TAU antra varianta, tai gali isreiksti savo
>> nuomone apie tai, kas mano schemoje negerai ir kas pasikeis sudejus
>> diodus? o mes va ne uz ilgo ir patikrinsim kiek tu teisybes parasysi.
>>
>>>
>>> http://www.electronics-tutorials.ws/amplifier/amp_7.html
>>> http://www.allaboutcircuits.com/vol_6/chpt_6/10.html galų gale, toks
>>> vaikiškas jau. Nes matau, esmės nelabai pagauni šitų reikalų....
>>>
>>>>>
>>>>> tai apie dvitaktį stiprintuvą gi kalbam, kitas petys bus jau seniai
>>>>> atsidaręs...
>>>>
>>>> NUSISNEKI. eik i o.binaries ir ziurek kol daeis. poto susiorganizuok
>>>> maketine ir prisimink ka mokeisi kazkada (jeigu).
>>>>
>>>>
>>>>>
>>
>