1974 Dialight Digital Display Catalog!
Added 2023-12-07 23:29:25 +0000 UTCA follow up to my recent video about the first big LED displays - now we have all the data! So, please enjoy the December 1974 Dialight Readout Selector Guide!
Comments
Wow! Seriously cool! 👍
Zygmunt Dean
2023-12-08 17:10:10 +0000 UTCOh, I love looking through old catalogs, I can spend hours absorbing their nostalgic goodness.
David Peaker
2023-12-08 12:40:01 +0000 UTCLove those old catalogs! It's amazing how long it took to brighten just the red LEDs. The early 70s Monsanto LEDs were dim and cost an absolute fortune. Never understood why a chemical company who brought us the wondrous PCB oil, Dioxin and Agent Orange products once made electronic components. I remember early 80s Radio Shack LED assortments and none of the LEDs were anywhere close to incandescent brightness. They had green, red and yellow/orange colors figured out, but it would take decades to finally develop a blue LED to enable full color mixing. I think the team that developed that blue LED solution won a Nobel prize that year. Now all LED colors can come in daylight-readable brightness levels surpassing incandescent lights many times over. Collins Avionics has been using the same Dialight socket and colored plastic domed lenses since the late 60s and they use the T1-3/4 bulbs that you could get from anywhere from 2.5V to 28V versions in the same bulb size. They got hot, but late 80s multi-chip LED drop-in replacements were still way too dim to displace the bulbs, and cost much more. They still use the Dialight sockets and caps that can be almost any color. There always had to be a "bulb test" button on the panels since Common 387 28V bulbs would burn out over time, as expected. But here's the damnedest thing... about 8 years ago Ledtronics came out with a daylight-visible LED with a very cold white output that cost a lot, at first, but could substitute all of the T1-3/4 bulbs. No more need for a "lamp test" button after those became the new accepted standard. But people hated them. They were WAY too bright and engineers would put Post-Its over columns of bulbs because they were so intense and annoying. The absolute cold white color also changes the colors of the lenses as well. The lenses were design for infra-red resistance of a WARM-white incandescent bulb. Aircraft pushbuttons with color filters behind engraved text in the button cap suddenly looked way off color and way too bright. To top it off, the Dialight lenses that have been in continuous use since the late 60s actually had the color in the plastic "bleached" after several months of being on. Red caps slowly turned orange, blue caps simply bleached into almost white and green caps would also reveal plastic bleaching. I didn't think it was possible to bleach the color out of plastic lenses, but I see that every day. As a very large customer, we tried to insist to Ledtronics that we needed a bulb replacement that is the SAME brightness level of an incandescent lamp and be WARM-white. That way, all of the legacy indicator lights, and message lights, would appear very close to the color temperature of the bulbs they replaced. And at the same intensity as well. I've never seen this kind of T1-3/4 LED yet and now the labs are filled with racks and panels filled with blinding little annunciator lights. If I have not already sent you some of these LEDS, let me know. It will make anything you put them in really turn into something you can't ignore!
Matt Wietlispach
2023-12-08 06:03:32 +0000 UTCSuper Cool!!!
Steph Traeger
2023-12-08 03:25:54 +0000 UTC
