Because I was already taken for an (I)ncandescent Lamp, and I was used
because L (Lamp) had been assigned to Inductor a great long time ago.

I recall lamps being DS.

John


Respectfully disagree, John. I grew up in the era of the #47 pilot lamp
being ubiquitous in radio dial lighting in everything I worked on that
needed backlighting or pilot lights. (I) was the standard; I never once saw
DS.

Jim