Scheme of polarity inverter, like max232 do?

[eldruida]

max232 scheme

Hello,

Sorry for my english.


I need a scheme, that inverts the polarity (+/- 12v), with signal ttl:
https://www.forosdeelectronica.com/proyectos/convertidor-TTL-RS232.htm

But it doesn't run.

Any idea where I can find other?

Thanks.

 

[FvM]

polarity inverter

I suggest to check circuits picked from the internet for correctness. In this case, Q1 has the wrong polarity, should be a pnp transistor (e.g. 2N2907) instead.

 

[eldruida]

transistor polarity inverter

Thank you very much!!!

It run?

You are a master,