To that end, Chris gifted me with a compact B&W CRT from Goodwill, and I picked up a TellyMate, which can display 38x25 text on a TV.
Ignoring for the moment the difficulty of receiving the WWVB signal when all the interference from a CRT TV is right nearby, I've created a mock-up of what the display will look like (except that the font won't be nearly so good looking as this):
0123456789 0.. 9 M01100000M Minute = 30 10..19 000000111M Hour = 07 20..29 000000110M YDay = 66 30..39 011000010M DUT1 = +0.3 40..49 001100000M Year = 2008 50..59 100001000M_ nols LY nodst Local time: 1:31:00.0 AM Thu Mar 6 2008 UTC-0600 (CST)
At the top, the WWVB data is displayed, along with its interpretation. The previous minute and the current minute are mixed, with the cursor indicating the most recently read second of data. Whatever piece of data is currently being read or will next be read will be blanked out until all bits are received (for instance, during seconds 0..8, "minute" will be blank; from 9..18, "hour" will be blanked).
Most of the time the "_" shown after second 59 will be blank. During a leap minute it will be "_" and during the leap second it will read "M".
Below, in larger lettering, the local time will be displayed. I think I can achieve 10 updates per second, so I'll show tenths but not hundredths (or, say, thirtieths). The UTC offsets for standard and daylight saving time will be hardcoded (so if I move to Colorado to be closer to WWVB I'll have to fix my firmware).
The WWVB receiver and decoder is written and passes my tests. I have yet to
write the display code (and optimize it--I can transmit fewer than 500
characters and control codes per 1/10 second to the tellymate), and I also have
to work out how to get enough reception that having the WWVB display is not a
big old waste of time. (or maybe I'll just display a simulated WWVB signal
instead—with a disclaimer, of course. stop looking at me like that.)
Entry first conceived on 6 March 2012, 1:41 UTC, last modified on 14 January 2013, 15:04 UTC
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