Amplificator casti

[Octavian95]

Salut! As avea si eu nevoie de o schema de amplificator de casti simplu pt. un radioreceptor. De fapt radioreceptor e mult spus pt. ca eu am conectat castile direct la iesirea din tuner. (dupa cum se vede si in poza)Nu doresc rezultate spectaculoase, doar vreau sa se auda mai tare ca in halul in care e acum se aude numai daca imi inghesui castile in urechi! Tot ce vreau e o schema usor de construit cu max. 1-2 tranzistori si in semireglabil pt. volum.

[George]

O schema simpla si fara prea mari pretentii. Poate fi alimentata intre 6 si 20 volti c.c.

Descriere:

"An amplifier to drive low to medium impedance headphones built using discrete components. Both halves of the circuit are identical. Both inputs have a dc path to ground via the input 47k control which should be a dual log type potentiometer. The balance control is a single 47k linear potentiometer, which at center adjustment prevents even attenuation to both left and right input signals. If the balance control is moved towards the left side, the left input track has less resistance than the right track and the left channel is reduced more than the right side and vice versa. The preceding 10k resitors ensure that neither input can be "shorted" to earth. Amplification of the audio signal is provided by a single stage common emitter amplifier and then via a direct coupled emitter follower. Overall gain is less than 10 but the final emitter follower stage will directly drive 8 ohm headphones. Higher impedance headphones will work equally well. Note the final 2k2 resistor at each output. This removes the dc potential from the 2200u coupling capacitors and prevents any "thump" being heard when headphones are plugged in. The circuit is self biasing and designed to work with any power supply from 6 to 20 Volts DC."

 

[leoncris]

viewtopic.php?f=13&t=46621

[Octavian95]

O schema simpla si fara prea mari pretentii. Poate fi alimentata intre 6 si 20 volti c.c.

Descriere:

"An amplifier to drive low to medium impedance headphones built using discrete components. Both halves of the circuit are identical. Both inputs have a dc path to ground via the input 47k control which should be a dual log type potentiometer. The balance control is a single 47k linear potentiometer, which at center adjustment prevents even attenuation to both left and right input signals. If the balance control is moved towards the left side, the left input track has less resistance than the right track and the left channel is reduced more than the right side and vice versa. The preceding 10k resitors ensure that neither input can be "shorted" to earth. Amplification of the audio signal is provided by a single stage common emitter amplifier and then via a direct coupled emitter follower. Overall gain is less than 10 but the final emitter follower stage will directly drive 8 ohm headphones. Higher impedance headphones will work equally well. Note the final 2k2 resistor at each output. This removes the dc potential from the 2200u coupling capacitors and prevents any "thump" being heard when headphones are plugged in. The circuit is self biasing and designed to work with any power supply from 6 to 20 Volts DC."

 

Schema pare OK dar oare functioneaza cu tunerul meu care lucra pe invers? Adica comunul de la iesire e + dupa cum e si in poza nu - cum e la alte tunere si aparate...

[andreivlad1999]

Va lucra cu tunerul tau daca nu alimentezi amplificatorul din aceeasi sursa cu tunerul. Daca vrei sa le alimentezi din aceeasi sursa atunci trebuie sa schimbi tranzistorii BC549(NPN) cu BC559(PNP), polaritatea condensatorilor electrolitici(10uF, 220uF si 2200uF) si a sursei.

[Octavian95]

Am decis sa construiesc varianta cu BC559 pt. ca vreau sa-l alimentez de la aceiasi sursa ca tunerul dar am o dilema: BC559C sau BC559B ? Am 2 buc. de fiecare dar care ar trebui sa-i pun?Care se potrivesc la amplificator mai bine? A si rog pe cineva sa-mi explice si mie ce inseamna literele alea dp. tranzistoare ca am mai intalnit si BC172A, B, C etc.

[bobo_romania]

Cel mai simplu este sa folosesti 2 integrate LM386.Componente externe putine,spatiu mic,putere mai mult decat suficienta.

[Den]

Si una bucata ne5532 e suficienta,gasesti in tuner cu ce sa il alimentezi.

[George]

Am decis sa construiesc varianta cu BC559 pt. ca vreau sa-l alimentez de la aceiasi sursa ca tunerul dar am o dilema: BC559C sau BC559B ? Am 2 buc. de fiecare dar care ar trebui sa-i pun?Care se potrivesc la amplificator mai bine? A si rog pe cineva sa-mi explice si mie ce inseamna literele alea dp. tranzistoare ca am mai intalnit si BC172A, B, C etc.

Pune cu litera C. Cei cu litera C au factor de amplificare mai mare decat cei cu litera B.

[geomx]

Cei cu litera C au factor de amplificare mai mare decat cei cu litera B.

@Octavian95 iti recomand ca sa mai deschizi si tu datasheet-ul unor componente ( in cazul de fata tranzistorii respectivi) asta ca sa mai si inveti ceva si sa nu fii nevoit sa intrebi mereu....