Has anybody used these?

Ravenkallen

http://www.adafruit.com/index.php?main_page=product_info&cPath=42&products_id=255

I just wanted to hear a second opinion before i rushed out and bought a bunch. I heard that they are way more accurate than a DS1307..

zappman

Hi Ravenkallen,

I have not tried one of those, if you buy one let us know how it works, it looks very interesting.

Too bad w4fej left the forums, because of a post by another user, w4fej might have made his Monty Hall Deal & gotten the Propeller Professional Demo Board he wanted. (Sorry this part is off topic)

Regards,

zappman

Ravenkallen

Yeah, well that is what happens when forum members start talking the law into their own hands...The Chronodot looks promising. I think i will but a couple. It brags about the ability to only lose a minute in a whole year...

Ron Czapala

I bought two from Macetech.com

They are more accurate than the DS1307.

See Demo http://www.maxim-ic.com/products/timers/DS3231_demo/

localroger

You can't permanently mount it. I know it looks cooler with the chip on top but with the battery underneath you pretty much have to unplug it from headers if you ever want to change the battery. installing it permanently isn't an option unless you desolder and reverse the headers.

I've used the SparkFun self-contained DS1307 module which is similar if perhaps not quite as accurate. This kind of thing is very convenient so you don't have to mess with the micropower and surface mount components yourself.

macegr

You could remove the headers and just use wires leading to the rest of the circuit, and mount the board using the holes provided. The battery is soldered in place anyway. The source is available so you could modify and build your own, or a new version with top-mounted battery holder may be available in a few months.

Franklin

You can't permanently mount it. I know it looks cooler with the chip on top but with the battery underneath you pretty much have to unplug it from headers if you ever want to change the battery. installing it permanently isn't an option unless you desolder and reverse the headers.

When these things first came out the first run had the headers on the other way (a mistake in fab) and you could not see the legend when they were plugged in. They sold them at half price as "Chrono-Doh"s

Ravenkallen

It said that the battery would last 8 years if you only used the device while it had power. I think i will buy at least one and see how it is...

Ravenkallen

So i bought one of these and so far i am very impressed. It seems to keep the time right on. It is also a better deal than the RTC breakout board that Sparkfun sells(Which uses a DS1307)
The DS3231 is a WAY better chip and hooking up your own requires very few external components....I highly recommend this device(One thing they could do is make the actual PCB a little smaller so it fits easier on a breadboard)

Ron Czapala

I set mine based on the "Official U.S. Time Clock" site several weeks ago and it appears to be a second off but of course there is the human factor of hitting enter at the precise moment :smilewinkgrin:

erco

We made a gag gift for a workmate which goes off every hour on the hour: lights, sound, motion. I considered a RTC like these, but ended up using a $10 wristwatch with an hourly chime function. We just use the beep output to the piezo crystal to trigger an EMC chip. Works perfectly, and the accuracy is amazing. I originally synched it to an atomic-updated clock and it has stayed accurate to within 20 seconds in 2 years.