In article , starman
wrote:

Remember that you will have to add a series resistor to limit the
current in each LED, otherwise they won't last long. Use Ohms law to
calculate the resistor value based on the source voltage and the
voltage/current ratings of the LED. I replaced the fifty-six (no typo!)
green LED's in my R8B display with just four bright white ones. The
display now looks blue-green with white charecters. The R8 was designed
before there were bright LED's, so Drake had to use an array of many
dozens of less bright ones to backlight the LCD display.

I *think* I might have found some original lamps for a decent price. I
have emailed them, and will report my findings.

Dan

Drake R8, Radio Shack DX-440,
Grundig S650, S700, S800, YB400
Tecsun PL-230 (YB550PE), Kaito KA1102
Hallicraters S-120 (1962)
Zenith black dial 5 tube Tombstone (1937)
E. H. Scott 23 tube Imperial Allwave in Tasman cabinet (1936)