How I Recycled an Old Florescent Tube Lamp to use LEDs.
I had a great lamp that had a florescent "Pure White' -type of bulb. It worked great - until the ballast up and died on me.
Rather than throw it away and find a new one, I decided to break out the old soldering iron and hack it with a few LEDs.
I used this site to calculate how much LEDs I could run with what power supplied. I calculated a total of 21 LEDs in 3 'strands' - one to point straight down and the other 2 to point up into the reflector. I used fritzing to both design the board I needed and to fabricate 2 boards (a spare just in case.)
This is just a few pictures, but shows what I did.