plz check this schematic for sim300

[sherazi]

i am making this circuit, the speaker and mic outputs are going to be amplified externally. so i am connecting them directly to RCA ports, i have almost no experience for audio circuits, so please check this schematic and give me some advice. the power supply section is OK i have tested it although its with minimum parts. the output is 4.18 volts.

 

[ckshivaram]

check this link
https://www.edaboard.com/threads/123266/

 

[sherazi]

can you check the rest of the circuit.. and regarding the link i couldn't get my answer from that.

 

[ea.arun]

hardware connections are very clearly mentioned in the sim300 hardware specification for both speaker and mic inputs....you might have to add some filter components.......refer to page number 30....
i remember i played around with the cap values due to noise........

 

[sherazi]

i have seen that but i was wondering if i am using mic and speaker amplifiers externally , can i connect the pins directly or do i need to connect it to the output and use only the caps mentioned there..