3 ms·
Sooooo how much power does that clock use ? Because simplest one would be: * a cheapo chinese subwoofer amplifier * 12V wall-wart to power it * a quartz-stabi
by ilyt 3y ago
Sooooo how much power does that clock use ?
Because simplest one would be:
* a cheapo chinese subwoofer amplifier
* 12V wall-wart to power it
* a quartz-stabilized 50Hz generator (soooo an arduino, with DAC, even simple R2R + some filtering).
* transformer fitting subwoofer amp output voltage. Measure amp output voltage at near-max, connect amplifier to secondary and tweak the "volume" till it is right.
Sub amp is like $5, $3 for cheapest arduino clone, probably like $2 for transformer, and few bucks in proto board and other components
If you want to overcomplicate it you could put rPi into it and sync the 50Hz clock to NTP
- seabass-labrax 3y agoWould you mind revealing where you would go to for a power transformer that cheap? Clearly they must exist, as a full AC/DC adapter costs barely more than that, but eBay is wont to give me listings for merchandise of a certain animated TV series...
- ilyt 3y agoAliexpress would be my first bet. Random used junk second https://www.aliexpress.com/w/wholesale-12V-220v-transformer.html?catId=0&initiative_id=SB_20230601042811&SearchText=12V+220v+transformer&spm=a2g0o.home.1000002.0 https://www.aliexpress.com/w/wholesale-12V-220v-transformer....
- amluto 3y ago> If you want to overcomplicate it you could put rPi into it and sync the 50Hz clock to NTP That’s ridiculous! Buy a little GPS-disciplined oscillator and either scale the PPS output up to 50Hz or use a PLL to derive 50Hz from the oscillator output :)
- BenjiWiebe 3y agoJust use a pll to derive 50 from 60. Problem solved.
- zbrozek 3y agoThe GPSDO will also give you correct time of day and unwavering frequency. I used to have one set up at home to feed my test equipment a 10 MHz reference.
- chromoblob 3y agoBut how do GPSDO work? Is GPSDO susceptible to metastability?
- zbrozek 3y agoGPS is a system for distributing time first and a means of computing position second. A GPSDO is typically a PLL that uses the recovered timebase as a reference input and will have an incredibly slow loop filter. It can be outrageously highly damped and stable. Such clocks are the basis of the cell network and have made doing client handoff between towers almost easy. The hard part is operating through GPS denial (mostly due to weather).
- ilyt 3y agoIf you're powering 50/60Hz clock you won't be setting time remotely on that easily
- coryrc 3y agoI've literally used an audio amplifier to directly create 240V 50Hz in a professional capacity so your idea is completely reasonable.
- ilyt 3y agoYeah I have prototype (working, sans transformer) somewhere on the pile of shame.