Sounds pretty similar to what I did. The white rectangle in my photo is a piece of white sticker vinyl stuck to the PCB under the area where the LCD mounts The two LEDs were sanded down with a Dremel tool and sanding drum to get the light to diffuse and also to make them small enough to shine behind the LCD panel. The two LEDs and a 680ohm current limiting resistor are all wired in series and draw a total of ~12ma off the 12V supply. Parts and wires are held in place by dabs of hot glue.
Here's a closeup of an original and modified LED. https://www.dropbox.com/s/vsf64g05jgc4mbl/100_0054.JPG?dl=0 On Saturday, December 4, 2021, 11:09:25 AM MST, David Gilbert <ab7e...@gmail.com> wrote: I made my own backlight for my K1 before the Elecraft version came out. It was actually more of a sidelight, but it works fine. I took a white LED, sanded the plastic case to make it more diffusive, and fed it off the 12 volt buss with a current source made from a gate-source connected FET. It wasn't difficult to do. I don't remember which FET I used, but an LM334 (very inexpensive TO-92 current source IC) and a 1/4 watt resistor would work even better, and today's LEDs are certainly much brighter than the ones I had available back when I did this. Better choice of colors as well. ;) 73, Dave AB7E On 12/4/2021 8:57 AM, Don Wilhelm wrote: > Ken, > > The K1 LCD backlight is no longer possible. The original used half of > the K2 backlight strip which is no longer available and the new K2 > strip is too thick to fit under the K1 LCD. > > 73, > Don W3FPR > > On 12/3/2021 11:39 PM, Ken Brown wrote: >> Need the best modifications for back lighting of the K1. >> This version never had the K1 LCD Backlight Kit. >> >> Ken >> Elecraft K1 nr. 260 >> > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to ab7e...@gmail.com ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to louand...@yahoo.com ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
