Seven-Segment LED, colors that seem to be in and out of fashion

[daveamkrayoguy]

Seems as though when clocks and other types of message screens first used seven-segment LED's, that red was mostly used...

Then came orange, after which it looked like everything had to be green and briefly blue...

Which I still see greatly used, but today, almost overnight, a lot of these displays are now mostly white...

What colors or hues have any if you seen?

-- Dave

 

[cfz2882]

LED colors

You missed yellow/amber
first came red,starting around 1968 for certain aerospace and commercial uses and then consumer products about 1975.
pale green LEDs started about 1975 i think,consumer products a couple years later.
yellow/amber around mid 1970s
orange seems to be rare,but seen in ~1978-86 GM cars.
took till 1993 for the first consumer-use blue LEDs,noticed white LEDs about 1996-those are blue LEDs with white-emitting phosphor covering the chip.
do not know when "true green"Leds appeared,but noticed them about 2002
A lot of 1970s desktop calculators,gas pumps,pinball machines,used orange-glowing neon gas 7-segment displays.
I haaate! white LEDs...

 

[joeekaitis]

Drool alert.

 

 

[cfz2882]

yes.

that is from about 1979-blue VFD

 

[DADoES]

 
Received this as a Christmas gift from the parents, all the many years ago.

 

[daveamkrayoguy]

Well honestly I don't recall the yellow/amber LED's but I'm sure they exist,.,

I practically grew up around the GM orange ones...

Your blue alarm clock radio sure reminds me of my Radio Shack that I know I paid more for to get the blue LED set whi,e everything else cheaper was run of the mill red... Can't find it so maybe it got given away...

My mom gave me her alarm clock radio done in green LED's that got put away while our basement is getting remodeled, we have to have a clock there as well as a plastic Regulatir battery powered pendulum clock that was in the laundry room,( need a clock there's too) but the wall there is torn down and I hung it in tne living room while the clock on the wall there is in the bathroom where I'd like to leave it...

There was a trend on appliances having green LED's as my coffee maker has it in green, my dad's old electric Maytag range did d so did my old Frigidaire gas range... So does my GE microwave abiuve it, and the microwave also a GE at my dad's but we had a fancy Tappan that I know one of the first that had blue...

Now my Samsung gas has blue, while my dad's GE electric has that white I'm afraid you might forever in that blandness see!

-- Dave

 

[cadman]

I think what some folks refer to as orange are really classified as yel/amber. This is what GM used in the late 70's on their high-end radios, then adopted by Cadillac in 1980+ for the Climate Control and Fuel Data displays. "Fun" fact, those displays were made by HP.

Prior to that it was difficult to get sufficient contrast for daylight viewing with traditional LEDs. Both Ford and GM used gas-discharge prior to that.

I do have some true orange 7-seg disps I bought years ago for novelty-sake. Not sure I've come across a consumer product that used them.

 

[cfz2882]

GM yellow/amber/orange LED display.

shade seems to vary some on those,some getting close to a proper orange,but starting amber at the chip for sure.Certain early 1980s Pontiac radios had red LED display and i have noticed HP logo on these GM Delco displays.Noticed true orange LED diodes about 1982 and found here and there-bought some new ones about 20 years ago(HP Telux-4 pin square package)and I had to dig around a bit to find those.My 1983 Radarange has a pale blue VFD with a red filter to appear amber in color-that method was quite ahead of it's time and would become common in the early '90s on VCRs,CD players,etc.

 

[daveamkrayoguy]

Well here’s one of the oldest working things in the house bought by its original owners:

My mom recommended an LED over a rotating dial when I wanted a digital clock and back when those diodes were mostly done in red…

The bulb in the nightlight got replaced and the first one lasted more years than the second that was in there of which it’s o it’s third…

Also all segments in each numeral work except sometimes noticeably the bottom one in the first set…

— Dave

 

[joeekaitis]

Lest we forget . . .

 

Most split-flap (or flip) clocks and electronic digital clocks from the same era were more accurate than today's retro recreations because the clock motor or timing circuit was controlled by the 60 Hz AC power line frequency, not a crystal oscillator.

 

[daveamkrayoguy]

Yes, the flip-flop clocks are what I meant, Joe...

Mom was against that type of unit fearing too much movement would wear out more than an analog or radial clock...

We had a range, however where the numbers turned on its digital clock, so I'm surprised a clock like that with that type of movement wasn't offered...

-- Dave

 

[cfz2882]

drum clocks in cars too...

...especially big GM boats of the early 1980s-the motor was reliable on these clocks,but after 20 or more years of operation the teeth on the drums would wear and the numbers would often not quite line up.

 

[joeekaitis]

The definitive bedside drum clock . . .

 

. . . was the Sankyo Digital 401, even though it lacked a lighted display.  The USA model was driven by a 120V 60Hz AC motor which gave it accuracy that lived up to their slogan "Never a Second Away From the Exact Time".

 

[circlew]

I had one of those Sankyo alarm clocks in white. Some friends gave it to me as a HS graduation present in 1974. I used it for several years until I bought a clock radio. Not sure if I still have it.

 

[cfz2882]

I have a Sankyo too-earlier model than the one in reply 12,i think it is from around 1972 and not lighted.runs good,not in regular use. I have a Sony flip clock radio from 1975,unusual clock lighting-orangish numerals glow green when lighted by a tiny cold cathode UV blacklight(that still lights good)The clock motor is a Telechron clone made by Omron and is stuck.

 

[daveamkrayoguy]

A lot of automotive dashboards used the drum design...

I even saw a drum design time display on a digital clock on an I love Lucy TV show...

Wonder why the design wasn't more widely used...

I loved our range that had one and a few other ranges with a digital clock I'd seen also had them...

One stereo I had used a small illuminated diode for its seven segment radio dial, which I think burned out so you couldn't see what station it was set on unless the bulb was replaced...

But I gave up that stereo for an analog dial that my in-laws gave me of which the bulbs after a couple replacements of I use to this day...

And I bought a flip-clock with the small bulb underneath it to illuminate it, which also had a radio with it and saw exactly what was potentially wrong with it and why it was recommended against it in seemingly planned-obsolescence in I found it cheaply-made...

-- Dave

 

[cfz2882]

earliest consumer LED clock...

...seems to have been a Texas Instruments bedside alarm clock released in the latter part of 1974-red display of course,and made in USA

 

[daveamkrayoguy]

TI was always ahead of any "its time", including the LCD, then LED calculator, and seemed to have headed the longest-put out RED L'ED's...

 

And maybe by a few years before other manufacturers and their colors and mass-produced 7-segments became prominent when they came out...

 

 

 

-- Dave

 

 

https://www.ti.com/