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
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
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
http://picasaweb.google.com/ve4yz.alan/RotatorRebuild2009#
Near the end of these images is a replacement of the lights. I found LED's with their built in lens too focused and not creating and even illumination across the meter. I went back to incandescent. The Source 13V 60ma with a diode in series to reduce the light and increase its life.
If you buy LEDs in a package they usually show a Voltage/Resistance/% illumination curve on the package. If you have an unknown bunch of LEDs you want to use, get a variable pot, set on max, use the voltage supply from the 5400 and reduce resistance until you get the illumination you want. Then replace the pot with an aproximate sized resistor.
-----Original Message----- From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Vince Fiscus, KB7ADL Sent: November 13, 2009 10:29 AM To: amsat-bb@amsat.org 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
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
participants (3)
-
Alan VE4YZ -
Howard Kowall -
Vince Fiscus, KB7ADL