
Let’s have some fun. Let’s build an LED menorah for the upcoming holidays.
1 HOUR
$1.27
EASY
PARTS
(2) 4 bright yellow LEDs (BG Micro $0.20)
(1) Yellow LED right angle (BG Micro $.012)
(1) SPST pushbutton (BG Micro $0.10)
(1) CR2032 with legs (BG Micro $0.65)
(1) Short length of wire
Instant bond cyanoacrylate glue
STEP-BY-STEP
Step 1. Bond the two 4-bright yellow LED bars together with glue.

Step 2. Fold down and solder all of the LED cathodes together. Repeat the same technique with the all of the LED anodes. You should now have a cathode run and an anode run.
Step 3. Bond the yellow LED right angle to the top of the joined LED bars.
Step 4. Fold and solder the LED right angle’s cathode to the bar’s cathode run. Likewise, fold and solder the LED right angle’s anode to the bar’s anode run.

Step 5. Snip off two adjacent legs (i.e., on the same side of the switch) from the SPST switch. The switch should now have two legs. Bond the SPST switch to one end of the joined LED bars. Solder one leg of the switch to the LED’s cathode run.
Step 6. Bond the CR2032 battery to the bottom of the joined LED bars. Solder the positive (+) leg to the anode run.

Step 7. Solder a short length of wire to the remaining free leg of the SPST switch. Solder the other end of the wire to the negative (-) leg of the CR2032 battery.
Step 8. Press the button to illuminate the LED Menorah.—Dave Prochnow
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aren't you supposed to light one candle per day for eight days?
...During a ceremony in which you use the top candle to light the others?
Maybe you could solder in one LED per day to do it properly.
an LED Menorah Headlamp comes to mind.
Last year we released a free (and open source) design for a tiny LED menorah based on a microcontroller that does light up the LEDs in the correct sequence, increasing by one "candle" each time that it's turned on.
(Conflict of interest note: We do sell kits as well.)
i put a small light keychaing thingy in my watch and lo abd behold..!!!! i made a watch with night vision