Hello group.
I'm probably in the wrong section, but what the heck. For some time now, I've been looking for a dual display led clock design. I can't be the only ham that wants one. It needs to show one display using a 24 hour format and the other using am/pm 12 hour format. It would also need to display seconds on both displays. I'm looking to use 6 digit displays that are at least .75", but 1.00" would be better. I would guess the time base could be a battery backed rtc board of any flavor. It doesn't matter which Arduino is used either. Another function that would be helpful would be a 9.5 minute timer that recycles and beeps and/or flashes an indicator as long as a switch is on. I don't have the wherewithal to design and program something right now because of some medical issues, but any help would be greatly appreciated. I know some of you guys are seriously incredible at design and programming the Arduino and I would be in your debt.
I got some great info from the forum section pertaining to LEDs about led driver and rtc modules from Member Paul. (Thank you sir!) He also directed me here.
A 9.5 minute timer ? You like your eggs hard boiled?
Have you considered simply using one display and swapping say every 2 seconds between 12 and 24 hour format? I do something a bit similar in that I scroll a date across a 4 digit clock every 9 seconds.
Actually the timer is to keep within the FCC rules. While transmitting and conversing, they require you to ID yourself every 10 minutes. Sometimes remembering how much time has passed while conversing. The UTC/local time display would have labels next to them for when both are reading AM and before 11:59 UTC or it might get confusing if you just glance at it. Thanks for the input though.
Ken
OK. Thanks. I knew there had to be a better explanation than you were simply trying to build a sophisticated egg timer. It wasn't clear (to me at least) from your original post that the 2 displays were intended for two different time zones (UTC and your local time zone).
If you require figures of 1", then I guess that you have to do it with multiple separate, single digit 7 segment displays. If you want a colon ':' to separate hours, minutes and seconds, you can sometimes do a trick with the decimal point by inverting some of the digits (so I heard on this forum).
KenW:
Actually the timer is to keep within the FCC rules. While transmitting and conversing, they require you to ID yourself every 10 minutes. Sometimes remembering how much time has passed while conversing. The UTC/local time display would have labels next to them for when both are reading AM and before 11:59 UTC or it might get confusing if you just glance at it. Thanks for the input though.
Ken
It is not hard to make a clock that strikes the hours. It would require only a small modification to strike once every 10 minutes instead.
odometer:
It is not hard to make a clock that strikes the hours. It would require only a small modification to strike once every 10 minutes instead.
That's an interesting idea. Though the 9.5 minute timer is preferred so you have a 30 second buffer to ID.
I think red displays will greatly simplify this thing.
Does it have to be LED? What about a large backlit LCD?
Not the right forum, but I have thought for a while that the super-cheap Android tablets can make great hobbyist projects. I can see a big dual-display clock made from a $30 7" tablet and a bit of code.
KenW:
I got some great info from the forum section pertaining to LEDs about led driver and rtc modules from Member Paul. (Thank you sir!) He also directed me here.
Hi again Ken. The free advice you get in this forum section will be of similar quality to the other forum sections. The point of posting here was for you to ask for help of someone to design the circuit and write and test the code for you. Someone may be willing to do this for you for free. You may have to offer an incentive.
I think he'd be more likely to get free help if not for the 1" display height. That pretty much puts it into custom hardware (or at least modification) territory since most off the shelf easy-to-use display are under 0.5" height.
The digits alone are going to run close to $50 and that's before adding drivers, controllers, firmware, etc.
If you want to do it with an arduino, the main effort lies in driving your output device: 7-segment, LCD, or maybe an OLED display. The actual logic beyond that isn't all that much of a big deal.
Seven segments and 6 displays (12, if you want 2 separate ones) is a lot of pins. I'd be inclined to hook up some shift registers.
Maybe I shouldn't suggest this here, but an android app might work better for this. Run it on a tablet and it will be plenty big, and the problem of driving an output device and getting the time is taken care of for you.
I did a quick search and found several that were 1" or bigger, but I think some cool pixie tubes would be a cool touch -- not quite as easy to build, though.
patduino:
I did a quick search and found several that were 1" or bigger, but I think some cool pixie tubes would be a cool touch -- not quite as easy to build, though.
It would be a nice touch for a ham being a ham
Pat.
I built some Nixie clocks years ago and had a handful of Pixie tubes that we're going to be put to use. Things changed and I sold off what I had. Those clocks were built using PIC processors programmed by someone that is much better at it then I am.
Ken
