mikalcarbine

I have an electric automotive fan being controller by a DCCONTROL FK-55 MOSFET PWM controller. It basically controls the fan via a temperature probe and a PWM signal based on the temperature of my radiator. I'd like to install a relay so the fan only turns on when the ignition is on but I'd also like full control (on, off, auto) of the fan. Luckily the controller has an input to do this, 12V = ON, open = AUTO and ground = OFF to the input. While speaking with my buddy he suggested parallel relays for diversity and mentioned a projection diode to protect the relay coil from surges, here is a basic circuit I create I have a SP3T switch with LEDs that I wish to wire up. The LED will light when the fan is on. I'm not sure if I need another relay for this or if the PWM signal from the controller will be enough. What does everyone think of this circuit?

Any other help?

That seems so pointless/such a nuisance. Does anyone have information on a dual section VCO that might fix this?

Hey forum! I've created a Bluetooth FM transmitter for my senior project by combining a WT32 Bluetooth Module with an FM Transmitter based off of the BH1417F and the circuit seen here: http://electronics-diy.com/BH1417_PLL_Stereo_FM_Transmitter.php I've fired the FM transmitter up for testing. Originally I set the frequency to 106.7 and tuned the variable inductor get a voltage roughly above 2v at the first test point (the point between the two 3.3k resistors and the 2.2nF cap). However when I switch to the opposite side of the FM band, ie 87.9, I am required to readjust the inductor the complete opposite way to achieve stable operation. Through some research I found these threads: http://www.electronics-lab.com/forum/index.php?topic=11519.msg62890 http://www.electronics-lab.com/forum/index.php?topic=10786.msg61621#msg61621 The second link is most important and on reply 2 it speaks of the exact problem I am having, however the attachment of the circuit fix is no longer valid :( Can anyone help me out or guide me in the right direction with this one? I'd like to be able to have all of the available FM band at my disposal without having to readjust the inductor every time.