The resistor value, R is given by:
R = (VS - VL) / I
VS = supply voltage VL = LED voltage (usually 2V, but 4V for blue and white LEDs) I = LED current (e.g. 20mA), this must be less than the maximum permitted
Here is the standard calculation
Howard
VE4ISP
----- Original Message ----- From: "Vince Fiscus, KB7ADL" vlfiscus@mcn.net To: amsat-bb@amsat.org Sent: Friday, November 13, 2009 10:29 AM Subject: [amsat-bb] Yaesu 5400B Az-EL rotor controller Lamps
Someone a while back mentioned using LED's as replacements for the meter lamps when they burn out. Can't remember who it was. Anyway, if you're still on the list, what value of resister did you use in series with the LED's? I think the OEM lamps were around 14 or 15 volts.
Thanks KB7ADL
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