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BLUE LED WRISTWATCH

Blue LED Wristwatch, retail $11.66 (www.gearbest.com...
Manufactured by (Unknown)
Last updated 03-12-18

I've only reviewed nine watches prior to this, so please bear with me here.

You might remember LED wristwatches from the 1970s, heck, you might still have one.

This is an LED watch that features a large display comprised of seven-segment LED "readouts"
It displays time in either 12 hour (regular AM/PM time) or 24 hour (military) format.

It can display the time & date like other digital watches, it also displays seconds if you require that feature, and it has a steel band.

SIZE

The LED wristwatch comes ready to use right out of the box. You may need to set the hour to the time zone you're in, and set the date as well - but is otherwise ready to go right away.

The wristband is a standard metal "snap" type; fasten it to your wrist & close the clasp until you hear it click.

To read the time, press & release the button on the upper right once. The time will be displayed for three seconds, and then automatically extinguish.

To read the date, press & release the button on the upper right twice in fairly quick succession. The date will be displayed for three seconds, and then automatically extinguish.

To read the seconds, press & release the button on the upper right three times in fairly quick succession. The seconds will be displayed for three seconds, and then automatically extinguish.

To set the watch, activate the time display by pressing & releasing the upper right button, then press & release the lower right button.

The watch will show the hours & minutes; the hours value will be flashing. Press the upper right button to change the hours value from 00 to 12. You may hold this button in to rapidly advance the hours value if desired.

Press the lower button once to cause the minutes value to flash. Press the upper button to change the minutes value from 00 to 59. You may hold this button in to rapidly advance the minutes value if desired.

Press the lower button once more to get the month & date on the screen - the "month" value will flash. Press the upper button to change it from 1 to 12; you may hold the button down to rapidly advance it.

Press the lower button once more to get the date value to flash. Press the upper button to advance the date from 1 to 31. You may hold this button in to rapidly advance the month value if desired.

Press the lower button to cause the year value to be displayed; press the upper button one or more times to get the year to change from 2000 to 2049. You may hold this button in to rapidly advance the year value if desired.

Press the lower button yet once more to cause the indicator to display "12hr" or "24hr"; press the upper button to toggle the two.

Finally, press the lower button again to finish up and turn your watch's display off.

It is not stated how the battery should be changed, so I don't have instructions for performing a battery change.

I believe that this watch uses a CR2032 lithium coin cell.

Because this is a watch and not a flashlight, I won't try to flush it down the potty, stomp on it with old or used bowling "shooz", viciously throw it at a wall or in the bathtub, smack it against a steel rod, run over it with my Quickie motorised wheelchair, or perform other potentially destructive tests on it that might be performed on a flashlight.

I did attempt to cut through the crystal (top window that protects the LED display) with the tip of the blade of a steak knife, and I was not successful.
This tells me that the crystal is made of glass (almost certainly mineral glass), not acrylic, polycarbonate, or other plastic.
Would I really try to cut up the crystal of a brand spanken new wristwatch I paid perfectly good money for?
You bet your sugar-coated toliet muscle (sweet patootie) I would, if it's in the name of science.

As a wristwatch, I think it's quite nice. And to see real live LEDs in it, that's even better.

I love LEDs and things made with them, and this watch is no exception

A picture showing the watch in its natural habitat, displaying the time.

A picture showing that the LED display is either in PWM mode or is multiplexed; either arrangement will help the battery last longer.
In this image, you can see the display is rapidly switching on and then off as I waved it in front of the camera while taking the photograph.

Spectrographic analysis of the LEDs in this wristwatch.

Spectrographic analysis of the LEDs in this wristwatch; spectrometer's response narrowed to a band between 455nm and 475nm to pinpoint emission peak wavelength, which is 465.61nm.

The raw spectrometer data (tab-delimited that can be loaded into Excel) is at bluwatch.txt

USB2000 Spectrometer graciously donated by P.L.

TEST NOTES:
Test unit was purchased on the Gearbest website on 11-02-17, and was received on the afternoon of 11-13-17.

UPDATE: 01-26-18
The gold plating on this watch is rather thin; this has caused the base metal to be exposed, which happens to be copper -- or something that LOOKS like copper anyway.
To wit:

UPDATE: 03-12-18
This wristwatch does not appear to honour Daylight Saving Time; but given the low cost, I didn't really expect it to.

MANUFACTURER: Unknown
PRODUCT TYPE: LED digital wristwatch
LAMP TYPE: Blue LED (seven segment-type LEDs)
No. OF LAMPS: At least 25 (discrete LEDs)
BEAM TYPE: N/A
SWITCH TYPE: Momentary pushbuttons for setting time, and date
CASE MATERIAL: Copper body, mineral glass crystal, copper band
BEZEL: Mineral glass crystal (window) protects LED display
BATTERY: (Suspected) 1x CR2032 lithium
CURRENT CONSUMPTION: Unknown/unable to measure
WATER- AND PEE-RESISTANT: No
SUBMERSIBLE: No
ACCESSORIES: 1x CR2032 cell
COUNTRY OF MANUFACTURE: China
WARRANTY: Unknown/not stated

PRODUCT RATING:

Because this product is not intended to emit
light, the standard "star" rating will not be used.

Blue LED Wristwatch * www.gearbest.com...

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