Original, non-backlit Elecraft K1 s/n 566, awaiting mod on the bench.
Post-mod K1, cheerfully backlit in the low light of my operating position.
I have been looking for a backlight mod for some time, and had even begun playing with some LEDs for edge-lighting the existing display, when I discovered that Elecraft now sells a backlight kit. The kit includes a new transflective LCD display and a very nice flat LED backlight. Installation instructions were excellent as usual, and installing the kit was pretty straightforward, but there were a few tricky spots.
The most difficult part of the installation when you are retrofitting to a built K1 is the removal of the old LCD display. There is the very real danger that you will lift a solder pad or trace. The instructions recommend that you cut off the old display leaving about 1/4" of the pins above board, and then remove one pin at a time. This is what I did, but in retrospect I would leave more of the pin in place, as I had some difficulty getting the pins free. I used a Soldapult suction tool to clear the solder from the holes after the pins were removed.
Here are some photos of the installation highlights:
I didn't take any photos of the removal of the old LCD display, and subsequent desoldering of the board holes. It was too horrible.
To hold the backlight panel in place while soldering the resistor and jumper to the board, I wrapped the assembly with trash bag twist-ties, twisting them until the unit was held tightly in place. Two ties twisted together were needed to wrap completely around the board.
To avoid damaging the backlight panel, I placed a pad of folded paper tower over the panel.
The resistor wire is soldered at the point just at the top right corner of S1.
Here is the LCD panel in place over the backlight, prior to being soldered in. I used another twist-tie to hold the display tight against the backlight before tacking it in place on opposite corners. Then I removed the twist-tie and soldered all of the display pins.
There is a very thin protective film in place over the display, that I did not remove until the display was fully soldered in place.
This is a very worthwhile mod, I would recommend that any new K1 builders consider adding the backlight as they build their new K1, it would be much easier to add at build time.
I chose the resistor to give the higher level of backlighting, and I am glad I did. This level of lighting consumes about 10ma -- over an 8-hour operating session that's 80maH, and considering I am using a 2300maH NiMH battery pack for portable operation, the 80maH doesn't seem significant.
Try it, you'll like it!