Historical clue formulations

• Some radio tubes — 2026-03-22
• Parts of LEDs — 2024-03-09
• Circuit board components — 2022-07-31
• Semiconductor devices — 2016-06-07
• Some electronic parts — 2012-03-15
• Some compact light sources — 2010-11-05
• Circuit components — 2010-08-19
• Circuit components — 2006-09-14
• Some semiconductors — 1994-03-05