Has your microwave clock jumped 20mins fast?

[SMc]

I used to live in Barbados- I took some stuff like clock radio etc from home rather than buy new when I got there and this was a common thing with the digital clocks- nobody told me this before but I just end up ignoring the clock in the end and got a wall clock

[Duane 3NE 2NR]

[fokhan_96]

Sooo the time on my car deck run fast by about 2 mins every month. Does this mean something wrong with my car.

[zoom rader]

[DMan7]

Sooo the time on my car deck run fast by about 2 mins every month. Does this mean something wrong with my car.

Well yuh know what to do...

[bluefete]

This happened to me as well a few weeks ago.

I was like WTH when I saw it the first time because I had never seen my stove clock speed up before.

I reset and it speeded up again.

But all seems to be normal now.

[SMc]

You trying to show off that you can't spell?

[dogg]

WTF!!

YES!!

I thought I was going crazy. Both microwave and stove went ahead 30 minutes

[Gladiator]

At random times all clocks by me (except the wrist watches) jump 5 mins ahead. Both battery and plug in clocks. They all do this on the same day and time. Go to work and everything normal come home and everything 5 mins fast. Two wall clocks (battery), microwave clock, projection wall clock (plug in) and $10 store battery clock.

I was trying to notice a pattern to put sense to what is happening but can't figure it out. It has not happened for this year so far but has me freaked out.

[BUG]

I've adjusted the time twice in 2 weeks, out by 20 minutes. Thought someone was playing tricks on me

[FrankChag]

Will have to chk my elec-eng bud, but this shud fix,, plug in microwave and stove.. pas de probleme

[phreakazoid]

This is more evidence to prove that we live in a simulation. We can't even trust the time. Who knows what is the real time anymore... sigh

[timelapse]

My wife does set it lol.

well i must be d only man who never bothered to ever set clock on my mw & stove ...

[Sōsuke Aizen]

Not sure how to check this 20 minute thing. Help pls

You sickening

[Team Loco]

no microwave no care lol

[MG Man]

Not sure how to check this 20 minute thing. Help pls

You sickening

you sexy

[maj. tom]

The 50/60 Hz in EU/SA is apparently an extremely important thing in Utility Frequency and they use atomic clocks to sync it exactly because it is used in any and everything with a microchip that controls time signals. Including the railways.

Sorry but that is referencing an analog clock circuit.

All digital circuits have a DC supply. DC is necessary to latch the transistors in the logic circuits. AC supplies are rectified and stepped down typically to the 1.0V to 24V range which is then provided to the board.

hmm ok, i understand. A microchip would generate a clock frequency using a piezo-crystal or an oscillator circuit using pure DC. I was thinking that a timer IC would use a dedicated half wave rectified signal waveform to generate pulses and then perform calculations on the function for an output at the required frequency. like this diagram:


https://www.electronics-tutorials.ws/po ... ation.html

Thanks for clearing that up.

So I was kind of half-way correct in my assumption btw. Been looking though some service manuals. This design is quite common in kitchen appliances. Not all appliances rely on an internal clock piezo crystal, they in fact do sync with commercial power AC frequency. Because it's cheaper, and because the application does not require precise timekeeping.

These are descriptions from several microwave oven service manuals on what the control circuit does and how it acquires the timing signal from a rectified AC signal. As in my diagram above.

_______________________________________________

_______________________________________________

_______________________________________________

______________________________________________________________________________________________

In one service manual I even found an entire description with diagrams of how this synchronous circuit generates the timing signal from the AC frequency supply.

“Most digital clocks in microwaves are frequency based. North America is on a 60 cycle frequency, it keeps time based on that, if the frequency of the AC increases, the clock will run faster, and if the frequency decreases, it will run slower. Are you on "shore power" or "generator power" ? Depending on the input frequency, the microwave clock will either be accurate (60 Hz), fast (>60Hz) or slow (<60Hz)”

So just to re-bump this topic, yes this explanation is correct. TTEC... well the power generation company really... has been sending a wonky 60 Hz frequency signal to the nation. Any devices not synced to a network and that relies on this AC frequency is not going to be accurate time at all.

[adnj]

The 50/60 Hz in EU/SA is apparently an extremely important thing in Utility Frequency and they use atomic clocks to sync it exactly because it is used in any and everything with a microchip that controls time signals. Including the railways.

Sorry but that is referencing an analog clock circuit.

All digital circuits have a DC supply. DC is necessary to latch the transistors in the logic circuits. AC supplies are rectified and stepped down typically to the 1.0V to 24V range which is then provided to the board.

hmm ok, i understand. A microchip would generate a clock frequency using a piezo-crystal or an oscillator circuit using pure DC. I was thinking that a timer IC would use a dedicated half wave rectified signal waveform to generate pulses and then perform calculations on the function for an output at the required frequency. like this diagram:


https://www.electronics-tutorials.ws/po ... ation.html

Thanks for clearing that up.

So I was kind of half-way correct in my assumption btw. Been looking though some service manuals. This design is quite common in kitchen appliances. Not all appliances rely on an internal clock piezo crystal, they in fact do sync with commercial power AC frequency. Because it's cheaper, and because the application does not require precise timekeeping.

These are descriptions from several microwave oven service manuals on what the control circuit does and how it acquires the timing signal from a rectified AC signal. As in my diagram above.

_______________________________________________

_______________________________________________

_______________________________________________

______________________________________________________________________________________________

In one service manual I even found an entire description with diagrams of how this synchronous circuit generates the timing signal from the AC frequency supply.

“Most digital clocks in microwaves are frequency based. North America is on a 60 cycle frequency, it keeps time based on that, if the frequency of the AC increases, the clock will run faster, and if the frequency decreases, it will run slower. Are you on "shore power" or "generator power" ? Depending on the input frequency, the microwave clock will either be accurate (60 Hz), fast (>60Hz) or slow (<60Hz)”

So just to re-bump this topic, yes this explanation is correct. TTEC... well the power generation company really... has been sending a wonky 60 Hz frequency signal to the nation. Any devices not synced to a network and that relies on this AC frequency is not going to be accurate time at all.

Well, no.

The circuit that you attached looks a lot like a PWM circuit to my eyes. It is likely used to control the cooking power by switching the HV transformer.

There have been designs that latched the AC signal to track time in kitchen appliances and clock radios but those were designs prior to the internet age.

Although AC cycle timekeeping is fairly accurate, an IC works better and is less expensive. If it can be programmed with a keypad, it almost certainly has a microcontroller.

Here's a generic microwave control circuit.

[Ben_spanna]

Sooo the time on my car deck run fast by about 2 mins every month. Does this mean something wrong with my car.

Well yuh know what to do...


]

Tiidas were never meant to have anything in them that works properly , including the driver.

[Duane 3NE 2NR]

The microwave and stove clock still runs fast every so often.
I assume other people still experiencing this also?

[K74T]

The microwave and stove clock still runs fast every so often.
I assume other people still experiencing this also?

Yup, I would set the correct time on both and after a few days I realize that both are 5 minutes faster.

[bluefete]

The microwave and stove clock still runs fast every so often.
I assume other people still experiencing this also?

Correct. Ironic though that this has come up again because just last week I saw the oven clock (electric) off by 5 minutes.

Battery powered clock on the wall runs like normal.

Clock in car loses its 2 minutes consistently for the past 15 years or so. LOL.

[Zim]

well i must be d only man who never bothered to ever set clock on my mw & stove ...

Makes 3 of us, mine is on 000 since installed