A aikiko New Member Mar 26, 2009 #1 Hello, I am making a little circuit to switch audio sources and it is many years that I haven t used electronic... How do I calculate the value of the resistor : **broken link removed** I hope the design is ok ? This is only the usefull part of my design. Thank you for you help.
Hello, I am making a little circuit to switch audio sources and it is many years that I haven t used electronic... How do I calculate the value of the resistor : **broken link removed** I hope the design is ok ? This is only the usefull part of my design. Thank you for you help.
Nigel Goodwin Super Moderator Most Helpful Member Mar 26, 2009 #2 No, the design is completely (and self destructively) wrong. The relay must be in series with the collector, and MUST have a protection diode across it. Check out the relay example in my tutorials The resistor isn't critical, it needs to be low enough to switch the transistor fully, and high enough to not overload the chip. Try something like 1K for a start.
No, the design is completely (and self destructively) wrong. The relay must be in series with the collector, and MUST have a protection diode across it. Check out the relay example in my tutorials The resistor isn't critical, it needs to be low enough to switch the transistor fully, and high enough to not overload the chip. Try something like 1K for a start.
A aikiko New Member Mar 27, 2009 #3 First of all thanks for you fast reply. I did not notice that the design was completely wrong, thanks for make me paying attention that it was completely wrong... **broken link removed** Now this is fixed i would like to ask you another ting : do you know if logic or gates can be found with a clock/enable signal ? Thanks
First of all thanks for you fast reply. I did not notice that the design was completely wrong, thanks for make me paying attention that it was completely wrong... **broken link removed** Now this is fixed i would like to ask you another ting : do you know if logic or gates can be found with a clock/enable signal ? Thanks