Off topic, but it's clock and it's old and it's digital...

80 views
Skip to first unread message

orange_glow_fan

unread,
Apr 16, 2022, 5:18:43 PMApr 16
to neonixie-l
I found this old digital clock several years ago and I'm wondering if anyone has any ideas as to its origins. While it works, I could use a schematic..

Also I need to somehow recreate the display segment mask! It looks like it was some kind of (??) film. This is a 6 digit clock and uses 42 cm344 midget bulbs! I don't even know if it's 12 or 24 hour format as 90% of the bulbs are bad. I think I can make out a single '1' digit at the extreme right so it's likely 12 hour format. 

I've included a few pictures that I hope help with identification and with the mask.

Thanks in advance....

Kerry
IMG_3470.JPGdown chassis.jpgdigit 1.jpgmask 1.jpgmask 2.jpg

John Rehwinkel

unread,
Apr 16, 2022, 5:34:09 PMApr 16
to neoni...@googlegroups.com
> I found this old digital clock several years ago and I'm wondering if anyone has any ideas as to its origins. While it works, I could use a schematic..

It looks like it may be a homemade one-off, however it seems pretty straightforward, and shouldn't be too much of a chore to reverse engineer the schematic.

> Also I need to somehow recreate the display segment mask! It looks like it was some kind of (??) film.

I might look at a custom gobo printing service like gammatech, projectorgram, or rosco to print a new mask. While I have tried laser printing transparencies, I wasn't really satisfied with the resulting contrast.

- John

Terry S

unread,
Apr 16, 2022, 7:12:50 PMApr 16
to neonixie-l
Agreed, clearly homebrew, and that transformer is running hot.

Mac Doktor

unread,
Apr 16, 2022, 8:36:02 PMApr 16
to neonixie-l

On Apr 16, 2022, at 5:34 PM, 'John Rehwinkel' via neonixie-l <neoni...@googlegroups.com> wrote:

Also I need to somehow recreate the display segment mask! It looks like it was some kind of (??) film.

I might look at a custom gobo printing service like gammatech, projectorgram, or rosco to print a new mask.  While I have tried laser printing transparencies, I wasn't really satisfied with the resulting contrast.

Another way to do this is to have it cut out of black vinyl and applied to the back side of a piece of clear acrylic. Vinyl will give you a very dense black, almost as good as paint or a silkscreen.

Any local sign shop can do this for you and If they say that it's too small to cut/weed cleanly go to another shop.


Here's an example. Many years ago I found a sign salesman's sample in a junk shop. It's built like a backlit sign that says "The Greasy Spoon & Tire Balancing Shop" perched on top of a tall pole except that it's the size of a suitcase and has a handle on top. A few years later I got heavily into decorating for Halloween and repurposed it for the occasion. At the time we had our own vinyl cutter and I made a Halloween sign out of it.

Here's my finished sign. I brought up the shadows a bit to make the outline more visible:


This picture is a long over-exposure taken at night so the letters are somewhat brighter than live and in person. The glow in the dark areas of the sign is light reflected back onto the shiny acrylic from the surrounding area, not leakage.


I should have used milky acrylic to diffuse the light but I didn't realize that until it was finished. I ended up taping sheets of paper over the openings. There are two pairs of light bulbs in it and a motor with a revolving cam that turns toggles a SPDT leaf switch back and forth. One pair are 90W yellow "bug" lights and the other two are 220W reds.




When the reds finally blow I guess I'll have to resort to magenta and pukey green LEDs.


Terry Bowman, KA4HJH
"The Mac Doctor"

https://www.astarcloseup.com

Q: Should car stereo speakers be pointed to the rear for more thrust or up for more traction?

A. On long trips, the 20- to 30% improvement in gas mileage you might get with speakers pointing to the rear is certainly worthwhile. On the other hand, if you drive on snow or ice, the extra traction of speakers pointing upward gives you added control.

Don Lancaster

Nick Andrews

unread,
Apr 17, 2022, 11:44:03 PMApr 17
to neoni...@googlegroups.com
Or even a t-shirt shop that does their own silk screening and such will likely have a cutter that could make a mask for you. 

--
You received this message because you are subscribed to the Google Groups "neonixie-l" group.
To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+...@googlegroups.com.
To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/41a3d82f-1d1d-44db-8fe6-3d048d469050n%40googlegroups.com.
Reply all
Reply to author
Forward
0 new messages