Slow Microwave Clock
jeff_wisnia
A few months ago I bought a new Westinghouse WST3501 microwave oven for
our office "eating area".
The oven itself works fine, but we're annoyed by the time of day clock
losing a couple of minutes a day and having to be reset to the correct
time every few days.
I've never seen this happen on several other microwave ovens I've had in
the office or at home, it's like the clock in this one isn't
synchronized to the 60 Hz line. Other line voltage operated clocks in
our office keep the correct time, unless there's a power failure and
they don't have a battery backup in them.
I'm guessing that the electronics in this "made in China" oven were
designed to run on 50 or 60 Hz power, with just a different power
transformer installed in 230 volt models. And, the clock is timed from a
poorly tuned and/or temperature sensitive crystal oscillator, not the
line frequency.
I e-mailed Westinghouse about this but they put me off to "Fox
International" who thusfar hasn't answered my e-mail about it.
Not an earth shaking problem by any means, but my curious mind wants to
know what's really going on with the clock function in that oven.
I'd just as soon put a pice of tape over the readout and fughedit, but I
can't do that because it's needed for the cooking functions too.<G>.
Jeff
--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.8*10e12 furlongs per fortnight.
The Daring Dufas
There could be a jumper on the control board to set 50 or 60 cycle power
as a time base. I've seen new equipment arrive with the wrong country
power plug installed. Products manufactured for the Southern Hemisphere
need electrons that spin in the opposite direction to work properly. You
may be able to obtain an electron spin converter if that's the problem.
TDD
jeff_wisnia
I actually thought about a jumper, but if there is one and it's set for
50 Hz operation that damn clock would gain 12 minutes PER HOUR, which
thank G_d it isn't.
Re the spin converter, is it based on something like this?
http://home.comcast.net/~jwisnia18/jeff/harm.html
HeyBub
> A few months ago I bought a new Westinghouse WST3501 microwave oven
> for our office "eating area".
>
> The oven itself works fine, but we're annoyed by the time of day clock
> losing a couple of minutes a day and having to be reset to the correct
> time every few days.
>
> I've never seen this happen on several other microwave ovens I've had
> in the office or at home, it's like the clock in this one isn't
> synchronized to the 60 Hz line. Other line voltage operated clocks in
> our office keep the correct time, unless there's a power failure and
> they don't have a battery backup in them.
>
> I'm guessing that the electronics in this "made in China" oven were
> designed to run on 50 or 60 Hz power, with just a different power
> transformer installed in 230 volt models. And, the clock is timed
> from a poorly tuned and/or temperature sensitive crystal oscillator,
> not the line frequency.
>
> I e-mailed Westinghouse about this but they put me off to "Fox
> International" who thusfar hasn't answered my e-mail about it.
>
> Not an earth shaking problem by any means, but my curious mind wants
> to know what's really going on with the clock function in that oven.
>
Take it back where you got it and bitch like the third monkey on Noah's
gangplank.
Peter
>
>
> A few months ago I bought a new Westinghouse WST3501 microwave oven for
> our office "eating area".
>
> The oven itself works fine, but we're annoyed by the time of day clock
> losing a couple of minutes a day and having to be reset to the correct
> time every few days.
>
[SNIP]
>
> I'm guessing that the electronics in this "made in China" oven were
> designed to run on 50 or 60 Hz power, with just a different power
> transformer installed in 230 volt models. And, the clock is timed from a
> poorly tuned and/or temperature sensitive crystal oscillator, not the
> line frequency.
>
Could be, but unlikely. The typical mass produced (and cheapest)
plug-in timers use circuits that count line frequency.
> I e-mailed Westinghouse about this but they put me off to "Fox
> International" who thusfar hasn't answered my e-mail about it.
>
> Not an earth shaking problem by any means, but my curious mind wants to
> know what's really going on with the clock function in that oven.
>
> I'd just as soon put a pice of tape over the readout and fughedit, but I
> can't do that because it's needed for the cooking functions too.<G>.
>
> Jeff
>
If a timing circuit designed to keep time with a 50 Hz AC supply was
connected to 60 Hz AC, I would expect the clock to run fast, not slow.
So the slow clock is not likely to be related to a wrongly placed jumper
or the use of a circuit designed for a 50 Hz supply.
I've had a chronic problem of the opposite kind in my house. Most but
not all of my digital clocks run a few seconds/day fast. I see this
with 1 of my 3 clock radios, both VCRs, my DVR, and the clock I've had
on every microwave (3 of them in about 20 years). There seems to be no
pattern to which home circuit the devices are connected to (happens to
devices connected to either 120V arm of my 240V service). Some of the
devices are 15+ years old, some are much more recent. Some are dual
voltage, some are 120V 60 Hz only. I convinced my electric power
company to come out and run diagnostics. They found absolutely nominal
readings with no evidence of voltage spikes, frequency deviations, RFI
or EMI. The engineer said he had been doing diagnostic work for the
same company for more than 10 years and no other customer has ever had a
similar complaint. I've resigned myself to making it a routine to reset
the time on all of these inaccurate devices at the beginning of each
month.
I hope the problem is restricted to my clocks. I'd hate to think that
something in this environment is also causing my biologic clock to run
fast and causing a shortened life expectancy :-) .
Give me back the old fashioned mechanical hysteresis motors! They never
ran fast or slow. They kept my old tube clock radios running accurately
for decades. I've got only one motor driven clock left, the one built
into my wall oven. Except for my "atomic" desk clock and "atomic" wrist
watch, that oven clock keeps the most accurate time in our house.
Jules Richardson
> Take it back where you got it and bitch like the third monkey on Noah's
> gangplank.
OK, I think that's just become my favourite saying for the week :-)
Jules Richardson
> I'm guessing that the electronics in this "made in China" oven were
> designed to run on 50 or 60 Hz power, with just a different power
> transformer installed in 230 volt models. And, the clock is timed from a
> poorly tuned and/or temperature sensitive crystal oscillator, not the
> line frequency.
that'd drift by a factor of 5/6, though.
> Not an earth shaking problem by any means, but my curious mind wants to
> know what's really going on with the clock function in that oven.
Interesting fault. I wondered if the clock was on its own oscillator and
is supposed to do a periodic resync against the line frequency (once a
day, say), with the "resync" part busted on yours - but I'm not sure that
makes sense either, because surely the clock would see 0 line pulses all
the time and reset itself to some default time each resync (unless the on-
board smarts say something like "there's obviously a fault with the pulse-
counter, I'll ignore it").
Bad parts, maybe. Perhaps someone goofed and a batch got made with the
wrong frequency crystal oscillator. Not sure if the manufacturer would
ever own up to that, though.
cheers
Jules
hr(bob) hofmann@att.net
wrote:
>
> - Show quoted text -
I'd hate to see what she will look like when she is 70 or 80 years
old, she'll need a wheelbarrow.
jeff_wisnia
a sealed carton) for $29.95 on sale at a Rite Aid pharmacy.
jeff_wisnia
Maybe she'll look something like the "older" pix here?
http://home.comcast.net/~jwisnia18/jeff/LOST/jefflost.html
The Daring Dufas
Some IC's have a built in clock that requires an external capacitor to
function. There is a probability of less than accurate cap values being
the culprit. Another thing that someone else posted on about problems
with his clocks and having tests done looking for interference coming
from the AC power. I know that transformers for office buildings had to
be redesigned after problems were discovered when the age of the
personal computer came along. All the switching power supplies were
causing overheating due to the asymmetrical loads put on the
transformers. I came across a simple power supply circuit that puts out
a clock signal from the 60Hz power. I understand that this design used
as a time base for a clock is susceptible to line noise.
http://preview.tinyurl.com/2fbtzht
The cheapness of many consumer electronics items today leads me to
believe that best practices are not being used in the design of the
circuitry. In an office environment there have got to be all kinds
of harmonics flooding the AC power system. If any of you guys are
like me, you notice things are off and not quite right with things
and can't stand it. I'll be out on a service call somewhere and
notice a loose screw on the door handle and I pull a screwdriver
out of my pocket to tighten up the errant screw. I once notified a
business owner that the toilet in the men's room was leaking and
he should call a plumber to fix it, he didn't think it was important
until he got a thousand dollar water bill. I like things to work
right and find conquering misbehaving systems to be a fun challenge.
Now if I could only figure out a way to repair women. 8-)
TDD
Charlie
>
> I've had a chronic problem of the opposite kind in my house. Most but not
> all of my digital clocks run a few seconds/day fast. I see this with 1 of
> my 3 clock radios, both VCRs, my DVR, and the clock I've had on every
> microwave (3 of them in about 20 years). There seems to be no pattern to
> which home circuit the devices are connected to (happens to devices
> connected to either 120V arm of my 240V service). Some of the devices are
> 15+ years old, some are much more recent. Some are dual voltage, some are
> 120V 60 Hz only. I convinced my electric power company to come out and
> run diagnostics. They found absolutely nominal readings with no evidence
> of voltage spikes, frequency deviations, RFI or EMI. The engineer said he
> had been doing diagnostic work for the same company for more than 10 years
> and no other customer has ever had a similar complaint. I've resigned
> myself to making it a routine to reset the time on all of these inaccurate
> devices at the beginning of each month.
>
using the power line for timing some process.
The question was raised of the accuracy of the line frequency. I got in
touch with a guy in Boston Edison' engineering office.
At that time IIRC the tolerance on the frequency was 1/10 of a cycle. He
pointed out that the root cause of the great Northeast blackout of 1964 was
caused not by a short circuit somewhere but by some undue surges on the
grid so that various generators got out of sync. That precipitated the
generators going off line to protect themselves. You readers who have ever
had a rotating machinery lab and tried to merge two generators together will
recall the caveats of throwing the switch before the two units were in
sync.
As another tidbit of our conversation was that the generating facility ran a
standard electric clock of their lines. At about midnight the task was to
slowly bring the clock to agree with the WWV time signal. The customer was
thus assured that they got all the cycles they were paying for.
There fore the best time to set your clock was about 3 am.
I am sure a lot has changed since then what with cesium clocks etc.
Somehow those days were more fun.
Charlie
WW
"jeff_wisnia" <jwisniaDu...@conversent.net> wrote in message
news:i9kp7q$pap$1...@news.eternal-september.org...
Jeff... Take it home and see if works correct there . That would show if
interference at office is the cause. WW
Nate Nagel
Used to have a Mr. Coffee coffeemaker w/ "analog" LCD clock. At least
twice a week it would just lock up and i'd have to "reboot" the
coffeemaker. Never happened once after I installed a TVSS at my panel.
I can only ASSume that the quality of the power was not so great.
nate
--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel
Smitty Two
jeff_wisnia <jwisniaDu...@conversent.net> wrote:
My older microwave lets me choose to not set the clock at all, but the
timing functions work as needed. When not in use, the display is blank /
black. I hate clocks. I don't own a watch, don't have a clock in the
bedroom. I keep one clock in the house, in the kitchen. That and the
clock on the corner of the computer monitor are all I need.
I go to sleep when I'm tired, wake up when I'm rested, eat when I'm
hungry. I don't understand humankind's obsessive fascination with time.
Ed Pawlowski
"Smitty Two" <prest...@earthlink.net> wrote
> I go to sleep when I'm tired, wake up when I'm rested, eat when I'm
> hungry. I don't understand humankind's obsessive fascination with time.
I do that to a point, but we often have to work together with others and be
at a particular place at a given time. The real obsessiveness started with
the railroads, then factories
HeyBub
Oh. Here's some more you might find useful:
You're circling the drain,
They gonna be drawin' you in chalk on the sidewalk,
Gave me the stink-eye
He needs flashlight therapy
'Roided up primate
Hold a grudge longer than my ex-wife
The medicine man's gonna be wavin' chicken claws over your ashes
And, when referring to a suspect, the following have been found to be
appropriate: Goblin, Gremlin, Squint, Slope, Miscreant, Do-bad, Slop-sucker,
Solid waste, and Chicken-plucker.
When you exhaust this set, just let me know. I've got a million of 'em.
HeyBub
Oooh! Good idea!
aemeijers
Not disagreeing with you, but unfortunately those people who deposit
great steaming piles of money in my bank account every two weeks expect
me to show up around the same time every day, etc.
That, plus I need to know when my TV shows are on, if I want to watch
them realtime.
--
aem sends...
HeyBub
>
> My older microwave lets me choose to not set the clock at all, but the
> timing functions work as needed. When not in use, the display is
> blank / black. I hate clocks. I don't own a watch, don't have a clock
> in the bedroom. I keep one clock in the house, in the kitchen. That
> and the clock on the corner of the computer monitor are all I need.
>
> I go to sleep when I'm tired, wake up when I'm rested, eat when I'm
> hungry. I don't understand humankind's obsessive fascination with
> time.
---
There may be reasons - as illustrated by the following joke:
My wife said "I need a new watch," and I replied "What for? There's a clock
on the stove."
---
Then there was the movie "Blue Thunder" where one character complained of
another: "He checks his sanity with a wrist watch?!"
To which the boss replied: "Whadda you check yours with, A dipstick?"
Bill Gill
working as a DJ at radio station in McAlester, Oklahoma. When they had
the big power black out in the North East their electric clock lost
several minutes of time. So they reset it. Then for a couple of weeks
they had to reset it every day, because it gained time, as the power
companies corrected the power line frequency to bring it back into sync
with the WWV time. The power line frequency is very stable over long
periods. As somebody said up thread the old fashioned electric clock
was extremely accurate over years. The power line frequency over short
periods is not particularly good, but over the long run it is about as
stable as you can get.
Bill
Peter
>
>
> The cheapness of many consumer electronics items today leads me to
> believe that best practices are not being used in the design of the
> circuitry. In an office environment there have got to be all kinds
> of harmonics flooding the AC power system. If any of you guys are
> like me, you notice things are off and not quite right with things
> and can't stand it. I'll be out on a service call somewhere and
> notice a loose screw on the door handle and I pull a screwdriver
> out of my pocket to tighten up the errant screw. I once notified a
> business owner that the toilet in the men's room was leaking and
> he should call a plumber to fix it, he didn't think it was important
> until he got a thousand dollar water bill. I like things to work
> right and find conquering misbehaving systems to be a fun challenge.
> Now if I could only figure out a way to repair women. 8-)
>
> TDD
If you don't break them, they don't need to be repaired. The key to
successful relationships with women who are important to you is to let
them have their way - or if you are really skillful, convincing them
that they are having their way even if you know better (also known as
child psychology).
Jon Danniken
>> Maybe she'll look something like the "older" pix here?
>
> http://home.comcast.net/~jwisnia18/jeff/LOST/jefflost.html
>
> Jeff
My EYES! They are BURNING!
ARGHHHH!
Jon
Jim Yanik
news:prestwhich-D4B2F...@mx01.eternal-september.org:
if you're paying for somebody's time(work),you have to be concerned with
time.(also you're being paid for -your- time.) If your business has set
business hours,it makes it better for customers;they can rely on your
business being open during posted hours,and thus you need your employees to
BE there at the proper times. Any business that is open at the whim of it's
owner or employees is going to lose business.
then there are TV shows;if you want to see the whole show,you have to be on
time.Or go to the movies,see the doctor,etc. Think of the phone and cable
guys who don't show up as scheduled,and how aggravating it is to wait on
them,when you could be doing something else. Or to miss a bus or plane
flight because you were late.
Then there's navigation;ships absolutely depend on accurate time to know
where they are and how to get where they want to be.
Satellite nav depends on very accurate time.
--
Jim Yanik
jyanik
at
localnet
dot com
Jim Yanik
the term is SWMBO;
She Who Must Be Obeyed.... 8-)
Mark Lloyd
[snip]
> I'd just as soon put a pice of tape over the readout and fughedit, but I
> can't do that because it's needed for the cooking functions too.<G>.
>
> Jeff
I don't need a clock on my microwave. I don't set it. The display is
blank except during cooking, other than the flashing word "time", which
is small enough to ignore.
--
66 days until The winter celebration (Saturday December 25, 2010
12:00:00 AM).
Mark Lloyd
http://notstupid.us
"I am an agnostic; I do not pretend to know what many ignorant men are
sure of." -- Clarence Darrow
HeyBub
>>
>> If you don't break them, they don't need to be repaired. The key to
>> successful relationships with women who are important to you is to
>> let them have their way - or if you are really skillful, convincing
>> them that they are having their way even if you know better (also
>> known as child psychology).
>>
>
> the term is SWMBO;
>
> She Who Must Be Obeyed.... 8-)
To repeat a life-learned lesson:
If she's happy and you're not, you're still happier than you would be if you
were happy and she was not.
SMS
> Jeff... Take it home and see if works correct there . That would show if
> interference at office is the cause. WW
If it's interference, go buy a 1500 watt UPS to run the microwave off
of. These are about $900.
Josh
wrote:
>On Tue, 19 Oct 2010 14:48:13 -0400, jeff_wisnia wrote:
>
>[snip]
>
>> I'd just as soon put a pice of tape over the readout and fughedit, but I
>> can't do that because it's needed for the cooking functions too.<G>.
>>
>> Jeff
>
>I don't need a clock on my microwave. I don't set it. The display is
>blank except during cooking, other than the flashing word "time", which
>is small enough to ignore.
Our microwave (built into the range hood) not only flashes in big
letters when the time needs to be set, but it also requires you to
enter the *date* (including the year) to set the time...and as far as
I can tell, never displays or uses the date again.
And of course it has no internal capacitor to handle a 1-2 second
power flicker; the slightest interruption (which fortunately is rare)
resets it.
Josh
Stormin Mormon
--
Christopher A. Young
Learn more about Jesus
www.lds.org
.
"jeff_wisnia" <jwisniaDu...@conversent.net> wrote in message
news:i9l724$9cd$1...@news.eternal-september.org...
Stormin Mormon
--
Christopher A. Young
Learn more about Jesus
www.lds.org
.
"The Daring Dufas" <the-dari...@stinky.net> wrote in message
news:i9llml$o03$1...@news.eternal-september.org...
How do you know when it's time to take your meds. The doctor said you
must take your Aripiprazole, Alprazolam and Campral at the correct
time
every day or there would be problems.
TDD
The Daring Dufas
My brother, Uncle Monster has a number of quotes called "Monsterisms"
and I help him add to the collection. One favorite is:
"Human females are genetically Machiavellian, they need little or no
training."
TDD
The Daring Dufas
My brother, Uncle Monster has a number of quotes called "Monsterisms"
Stormin Mormon
More seriously. I run late for everything. Which has got me written
up, at jobs. I like that life style. Stay in tune with your body, and
take it slow.
--
Christopher A. Young
Learn more about Jesus
www.lds.org
.
"Smitty Two" <prest...@earthlink.net> wrote in message
news:prestwhich-D4B2F...@mx01.eternal-september.org...
k...@att.bizzzzzzzzzzzz
Television? Real time? How do you skip commercials?
Red Green
@news.eternal-september.org:
>
>
> Maybe she'll look something like the "older" pix here?
>
> http://home.comcast.net/~jwisnia18/jeff/LOST/jefflost.html
>
> Jeff
>
> --
> Jeffry Wisnia
> (W1BSV + Brass Rat '57 EE)
> The speed of light is 1.8*10e12 furlongs per fortnight.
>
>
Maaan, that's rough. Suggest Googling house jacking.
Red Green
>
> Maybe she'll look something like the "older" pix here?
>
> http://home.comcast.net/~jwisnia18/jeff/LOST/jefflost.html
>
> Jeff
>
> --
> Jeffry Wisnia
> (W1BSV + Brass Rat '57 EE)
> The speed of light is 1.8*10e12 furlongs per fortnight.
>
This might be her more shy sister. Hard to believe the one in the
background with red top and jeans may be a foreground runner in the future.
Gary H
[snip]
>
> Television? Real time? How do you skip commercials?
Look away from the screen and do something else.
The Daring Dufas
> hr(bob) hof...@att.net wrote:
>
>> On Oct 19, 2:31 pm, jeff_wisnia <jwisniaDumpThisP...@conversent.net>
>> wrote:
>>
>>> The Daring Dufas wrote:
>>>> power
>>>> as a time base. I've seen new equipment arrive with the wrong country
>>>> power plug installed. Products manufactured for the Southern Hemisphere
>>>> need electrons that spin in the opposite direction to work properly.
>>>> You
>>>> may be able to obtain an electron spin converter if that's the problem.
>>>
>>>> TDD
>>>
>>> I actually thought about a jumper, but if there is one and it's set for
>>> 50 Hz operation that damn clock would gain 12 minutes PER HOUR, which
>>> thank G_d it isn't.
>>>
>>> Re the spin converter, is it based on something like this?
>>>
>>> http://home.comcast.net/~jwisnia18/jeff/harm.html
>>>
>>> Jeff
>>>
>>> --
>>> Jeffry Wisnia
>>> (W1BSV + Brass Rat '57 EE)
>>> text -
>>>
>>> - Show quoted text -
>>
>>
>> I'd hate to see what she will look like when she is 70 or 80 years
>> old, she'll need a wheelbarrow.
>
>
> Maybe she'll look something like the "older" pix here?
>
> http://home.comcast.net/~jwisnia18/jeff/LOST/jefflost.html
>
> Jeff
>
Back when I was in the Hippies about four decades ago, girls were not
getting tattoos like today, it wasn't a common sight. A guy might get
one earring like a pirate but not the body piercings that are common
in this century. Tattoos didn't become a fad until all the movie and
pop music stars started all that nonsense. I wonder what the children
of the extreme body modification crowd are going to do to shock their
physically modified parents? Perhaps the little tykes will become
extreme, button down, super religious, Republican Conservatives? 8-)
TDD
aemeijers
That is when I proof-read and hit 'send' on my posts here on Usenet, or
finish the article in the paper I was reading.
I almost never JUST watch TV. It is more of a fireplace for me-
flickering lights, and since I live alone, the illusion of human
presence and voices in the vicinity. My DVR keeps filling up, because it
takes too much attention to watch recorded shows while I am doing
something else.
--
aem sends...
k...@att.bizzzzzzzzzzzz
That doesn't do the whole job.
Daniel Prince
>The key to
>successful relationships with women who are important to you is to let
>them have their way
You also have to let them win EVERY argument, even when they are
wrong, especially when they are wrong.
--
I don't understand why they make gourmet cat foods. I have
known many cats in my life and none of them were gourmets.
They were all gourmands!
LouB
> Peter <pk...@netzero.com> wrote:
>
>> The key to
>> successful relationships with women who are important to you is to let
>> them have their way
>
> You also have to let them win EVERY argument, even when they are
> wrong, especially when they are wrong.
LOL