Thank you very much, Jim. Exactly what i was looking for. Thanks again,
Regards. --- In [email protected], Jim Brown <w5...@...> wrote: > > Here is the circuit I would recommend to light an LED when the signal input > is at or near ground and will extinguish the LED when the input is at or near > + 5 VDC. It would provide minimal loading on a microprocessor output signal. > > 73 - Jim W5ZIT > > --- On Fri, 9/25/09, tait700 <cscan...@...> wrote: > > From: tait700 <cscan...@...> > Subject: [Repeater-Builder] Busy Signal (COS) inverter Circuit. > To: [email protected] > Date: Friday, September 25, 2009, 6:33 AM > > > > > > > > > > > > > Hello, > > Was wondering if someone knowledgeable would be able to advise me on the best > way to proceed with this, > > I need to extract a signal to power a normal LED that indicates when the Mute > has opened on a Receiver. > > The Receiver has a "Busy" line coming from the Micro that supplies 5V DC when > the mute is closed ( Quiet ) and goes to OV when the Audio is open ( Audible ) > > I don't have any further info on the current available from the micro and am > a little dubious about running a small SPDT relay off this signal. > > I searched the RB site and found the article concerning the "maxtrac cor > buffer" which uses a Transistor to invert the logic but am not sure how to > apply this to a LED ( 20ma ) and whether the resistor on the Base input would > be the right value. > > If i could do this without risking the health of the micro ( which controls > everything on the Board ) i would be very happy. > > > > Any info would be most appreciated, > > > > Regards, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > __________________________________________________ > Do You Yahoo!? > Tired of spam? Yahoo! Mail has the best spam protection around > http://mail.yahoo.com >
