Hi

Is there any problem with investigating the internal of a microwave oven ?
Not turning it on of course. 

Mine has developed an intermittent rattle, which stops if you press on the case
side and I suspect it is just something slightly loose but I have no means of
testing it, once the case is replaced or should I just bin it ?

Andy

Andy Cap wrote:
> Hi
>
> Is there any problem with investigating the internal of a microwave
> oven ?
> Not turning it on of course.
>
> Mine has developed an intermittent rattle, which stops if you press
> on the case side and I suspect it is just something slightly loose
> but I have no means of testing it, once the case is replaced or
> should I just bin it ?
>
> Andy

I believe they have a huge capacitor or two inside them. Also you can get 
quite a good belt off the turntable motor if you spin it manually whilst 
touching the contacts. DAMHIK, IJK.

Si

On 17 Jul, 11:40, Andy Cap  wrote:
> Hi
>
> Is there any problem with investigating the internal of a microwave oven ?
> Not turning it on of course.
>
> Mine has developed an intermittent rattle, which stops if you press on the case
> side and I suspect it is just something slightly loose but I have no means of
> testing it, once the case is replaced or should I just bin it ?
>
> Andy

Shouldn't be - they only radiate when powered up. As with any
electrical equipment be wary of the capacitors which may still hold
charge, even long after the equipment has been powered down. The
capacitors in microwaves are particular high capacity. In my
microwave, there is a huge red warning sticker attached to the
capacitors to make this clear, but yours may not have this. If you
have any doubts about what a component is, don't touch it!

dan.

On 17 Jul, 11:40, Andy Cap  wrote:

> Is there any problem with investigating the internal of a microwave oven ?
> Not turning it on of course.

There's a fatal charge waiting on the capacitors inside it. There
_ought_ to be discharge resistors across them, but you never trust
those things. Don't open the case for an hour or two after power, then
make sure to discharge the capacitors with an insulated probe, in case
the resistors were what had fallen off!  This probe needs insulation
to HT standards, so a clean, dry rod handle of glass or non-conductive
(i.e. transparent, so you can see there's no carbon filler in it)
plastic is needed. Aldi are selling packs of cheap knitting needles in
bright transparent colours at present, which make excellent support
insulators if you're making steampunk Wimshurst machines.

Personally I'd leave it a day first.

Web searching the Tesla Coil and Jacob's Ladder building sites will
suggest much about what to do with the innards of a microwave.

Andy Cap used his keyboard to write :
> Hi
>
> Is there any problem with investigating the internal of a microwave oven ?
> Not turning it on of course. 
>
> Mine has developed an intermittent rattle, which stops if you press on the 
> case side and I suspect it is just something slightly loose but I have no 
> means of testing it, once the case is replaced or should I just bin it ?

The capacitors inside can store a couple of thousand volts for quite a 
long time. They are supposed to be fitted with a high value resistor to 
discharge them, but that can go faulty. Best to make sure these are 
discharged before probing about inside.

-- 
Regards,
        Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

On Thu, 17 Jul 2008 17:11:26 +0100, Harry Bloomfield
 wrote:

>Andy Cap used his keyboard to write :
>> Hi
>>
>> Is there any problem with investigating the internal of a microwave oven ?
>> Not turning it on of course. 
>>
>> Mine has developed an intermittent rattle, which stops if you press on the 
>> case side and I suspect it is just something slightly loose but I have no 
>> means of testing it, once the case is replaced or should I just bin it ?
>
>The capacitors inside can store a couple of thousand volts for quite a 
>long time. They are supposed to be fitted with a high value resistor to 
>discharge them, but that can go faulty. Best to make sure these are 
>discharged before probing about inside.

Thanks to everyone who's warned of the dangers. I will take a careful look over
the next few days.

Andy

"Andy Cap"  wrote in message 
news:a6su74pdv2ftles0no9sbsfi4d7fooek7t@4ax.com...
> On Thu, 17 Jul 2008 17:11:26 +0100, Harry Bloomfield
>  wrote:
>
>>Andy Cap used his keyboard to write :
>>> Hi
>>>
>>> Is there any problem with investigating the internal of a microwave oven 
>>> ?
>>> Not turning it on of course.
>>>
>>> Mine has developed an intermittent rattle, which stops if you press on 
>>> the
>>> case side and I suspect it is just something slightly loose but I have 
>>> no
>>> means of testing it, once the case is replaced or should I just bin it ?
>>
>>The capacitors inside can store a couple of thousand volts for quite a
>>long time. They are supposed to be fitted with a high value resistor to
>>discharge them, but that can go faulty. Best to make sure these are
>>discharged before probing about inside.
>
> Thanks to everyone who's warned of the dangers. I will take a careful look 
> over
> the next few days.

I had one that was making noises and overheating..
took the back off and a big warning label had detached itself from somewhere 
inside and had jammed the fan.
It worked after removing it but was never quite as powerful as before so 
something was damaged.
Chucked it and bought a new one for ~£40.

Andy Cap wrote:

> Thanks to everyone who's warned of the dangers. I will take a careful look over
> the next few days.

Many moons ago... I had a brilliant Panasonic combination oven I couldn't stand 
the thought of dumping as it cost me around £500 when I bought my first house...
Microwave had packed up and general opinion was the big capacitor was shot.
Got a new one mailorder, fitted and lo & behold the beauty was revived.

As others have said, a big cap. can give one hell of a belt if it's not 
discharged.
Been there, done that.
8¬O

Pete

-- 
http://gymratz.co.uk - Fitness & Gym Equipment/nutrition specialists.
http://www.trade-price-supplements.co.uk - Bulk buy for up to 33% off.
http://www.BBE-Boxing-Equipment.co.uk - New Boxing Equipment site.
http://www.commercial-gym-equipment.co.uk - Commercial Gym Equipment.

On Jul 17, 11:40 am, Andy Cap  wrote:
> Hi
>
> Is there any problem with investigating the internal of a microwave oven > Not turning it on of course.
>
> Mine has developed an intermittent rattle, which stops if you press on the case
> side and I suspect it is just something slightly loose but I have no means of
> testing it, once the case is replaced or should I just bin it ?
>
> Andy

Putting newspaper between it and whatever its next to might be easier.

That capacitor is the biggest safety deal in nukes. Advice to leave it
24hrs does not inspire confidence, if the discharge resistor is o/c
chances are it can still kill you after a week. Avoiding the cap
doesnt work, the wires will conduct the lethal charge around the
place. Only safe option is to discharge it before getting in there.
Attach a wire from cooker case to screwdriver shaft, and use the blade
to touch _both_ cap terminals _together_. Screwdriver must be
insulated and hands kept away from bare shaft. People have died
servicing nukes.


NT

On Jul 18, 3:34 pm, meow2...@care2.com wrote:

> That capacitor is the biggest safety deal in nukes. Advice to leave it
> 24hrs does not inspire confidence, if the discharge resistor is o/c
> chances are it can still kill you after a week. Avoiding the cap
> doesnt work, the wires will conduct the lethal charge around the
> place. Only safe option is to discharge it before getting in there.
> Attach a wire from cooker case to screwdriver shaft, and use the blade
> to touch _both_ cap terminals _together_. Screwdriver must be
> insulated and hands kept away from bare shaft. People have died
> servicing nukes.

If the capacitor is that big, you'd better put safety goggles on
before shorting it with a screwdriver. Better to use a resistance. My
boss who should have known better, tested a large capacitor with a 5kv
tester. I wondered why it took several seconds to reach the 5kv. When
he shorted it with a screwdriver it blew the end off the steel
screwdriver and bits of flying molten solder went everywhere.

On 2008-07-17, Andy Dingley  wrote:
> On 17 Jul, 11:40, Andy Cap  wrote:
>
>> Is there any problem with investigating the internal of a microwave oven ?
>> Not turning it on of course.
>
> There's a fatal charge waiting on the capacitors inside it. There
> _ought_ to be discharge resistors across them, but you never trust
> those things. Don't open the case for an hour or two after power, then
> make sure to discharge the capacitors with an insulated probe, in case
> the resistors were what had fallen off!  This probe needs insulation
> to HT standards, so a clean, dry rod handle of glass or non-conductive
> (i.e. transparent, so you can see there's no carbon filler in it)
> plastic is needed. Aldi are selling packs of cheap knitting needles in
> bright transparent colours at present, which make excellent support
> insulators if you're making steampunk Wimshurst machines.
>
> Personally I'd leave it a day first.
>
> Web searching the Tesla Coil and Jacob's Ladder building sites will
> suggest much about what to do with the innards of a microwave.

SIDE!


-- 
          "Be thankful that you have a life, and forsake your vain
                 and presumptuous desire for a second one."
               [email me at huge {at} huge (dot) org <dot> uk]

On 2008-07-17 16:22:46 +0100, Huge <Huge@nowhere.much.invalid> said:

> On 2008-07-17, Andy Dingley  wrote:
>> On 17 Jul, 11:40, Andy Cap  wrote:
>> 
>>> Is there any problem with investigating the internal of a microwave oven ?
>>> Not turning it on of course.
>> 
>> There's a fatal charge waiting on the capacitors inside it. There
>> _ought_ to be discharge resistors across them, but you never trust
>> those things. Don't open the case for an hour or two after power, then
>> make sure to discharge the capacitors with an insulated probe, in case
>> the resistors were what had fallen off!  This probe needs insulation
>> to HT standards, so a clean, dry rod handle of glass or non-conductive
>> (i.e. transparent, so you can see there's no carbon filler in it)
>> plastic is needed. Aldi are selling packs of cheap knitting needles in
>> bright transparent colours at present, which make excellent support
>> insulators if you're making steampunk Wimshurst machines.
>> 
>> Personally I'd leave it a day first.
>> 
>> Web searching the Tesla Coil and Jacob's Ladder building sites will
>> suggest much about what to do with the innards of a microwave.
> 
> SIDE!

Switch Off
Isolate
Dump
Earth


I remember seeing a short documentary about that with two guys in a 
lab.   One goes off to the dentist and the other has the task of 
rewiring the experiment.   Imagine his surprise when he touches a 
screwdriver somewhere unexpected and there is a flash and a loud report

"Matty F"  wrote in message 
news:22efeae0-ff5a-4430-8444-f9a6a1b1868e@u12g2000prd.googlegroups.com...
> On Jul 18, 3:34 pm, meow2...@care2.com wrote:
>
>> That capacitor is the biggest safety deal in nukes. Advice to leave it
>> 24hrs does not inspire confidence, if the discharge resistor is o/c
>> chances are it can still kill you after a week. Avoiding the cap
>> doesnt work, the wires will conduct the lethal charge around the
>> place. Only safe option is to discharge it before getting in there.
>> Attach a wire from cooker case to screwdriver shaft, and use the blade
>> to touch _both_ cap terminals _together_. Screwdriver must be
>> insulated and hands kept away from bare shaft. People have died
>> servicing nukes.
>
> If the capacitor is that big, you'd better put safety goggles on
> before shorting it with a screwdriver. Better to use a resistance. My
> boss who should have known better, tested a large capacitor with a 5kv
> tester. I wondered why it took several seconds to reach the 5kv. When
> he shorted it with a screwdriver it blew the end off the steel
> screwdriver and bits of flying molten solder went everywhere.

Most microwave capacitors have built in 15Meg resistor and discharge pretty 
quickly, in minutes...

Andy Cap wrote:
> Hi
> 
> Is there any problem with investigating the internal of a microwave oven ?
> Not turning it on of course. 
> 
> Mine has developed an intermittent rattle, which stops if you press on the case
> side and I suspect it is just something slightly loose but I have no means of
> testing it, once the case is replaced or should I just bin it ?
> 

Today's "news" story about defibrillators and swimming pools (together 
with this thread) inspires the thought that the kitchen microwave could 
form part of the core equipment for the d-i-y "Home Hospital and 
Operating Theater" (TM).

Waveguide out and you've got radio-frequency diathermy machine as well.

Brain surgery with Bosch cordless drills already covered.

-- 
Rod

Hypothyroidism is a seriously debilitating condition with an insidious 
onset.
Although common it frequently goes undiagnosed.
<www.thyromind.info> <www.thyroiduk.org> <www.altsupportthyroid.org>

On 2008-07-18, Andy Hall <andyh@hall.nospam> wrote:
> On 2008-07-17 16:22:46 +0100, Huge <Huge@nowhere.much.invalid> said:
>
>> On 2008-07-17, Andy Dingley  wrote:
>>> On 17 Jul, 11:40, Andy Cap  wrote:


>>> Web searching the Tesla Coil and Jacob's Ladder building sites will
>>> suggest much about what to do with the innards of a microwave.
>> 
>> SIDE!
>
> Switch Off
> Isolate
> Dump
> Earth

Give that man a cee-gar.

> I remember seeing a short documentary 

Wasn't it one of those day-time fill-in programs that existed before Jeremy
Kyle?

-- 
          "Be thankful that you have a life, and forsake your vain
                 and presumptuous desire for a second one."
               [email me at huge {at} huge (dot) org <dot> uk]

"Harry Bloomfield"  wrote in message 
news:mn.8c077d87655a692b.86812@NOSPAM.tiscali.co.uk...
> Andy Cap used his keyboard to write :
>> Hi
>>
>> Is there any problem with investigating the internal of a microwave oven 
>> ?
>> Not turning it on of course.
>> Mine has developed an intermittent rattle, which stops if you press on 
>> the case side and I suspect it is just something slightly loose but I 
>> have no means of testing it, once the case is replaced or should I just 
>> bin it ?
>
> The capacitors inside can store a couple of thousand volts for quite a 
> long time. They are supposed to be fitted with a high value resistor to 
> discharge them, but that can go faulty. Best to make sure these are 
> discharged before probing about inside.
>
> -- 
> Regards,
>        Harry (M1BYT) (L)
> http://www.ukradioamateur.co.uk
>


Is there an easy way I could incorporate one of these into a squirrel trap 
that currently only serves as a squirrel, free meal station?

S

"Ian_m"  wrote in message 
news:B7ydnVGIq-3z5h3VnZ2dnUVZ8h-dnZ2d@pipex.net...
> "Matty F"  wrote in message 
> news:22efeae0-ff5a-4430-8444-f9a6a1b1868e@u12g2000prd.googlegroups.com...
>> On Jul 18, 3:34 pm, meow2...@care2.com wrote:
>>
>>> That capacitor is the biggest safety deal in nukes. Advice to leave it
>>> 24hrs does not inspire confidence, if the discharge resistor is o/c
>>> chances are it can still kill you after a week. Avoiding the cap
>>> doesnt work, the wires will conduct the lethal charge around the
>>> place. Only safe option is to discharge it before getting in there.
>>> Attach a wire from cooker case to screwdriver shaft, and use the blade
>>> to touch _both_ cap terminals _together_. Screwdriver must be
>>> insulated and hands kept away from bare shaft. People have died
>>> servicing nukes.
>>
>> If the capacitor is that big, you'd better put safety goggles on
>> before shorting it with a screwdriver. Better to use a resistance. My
>> boss who should have known better, tested a large capacitor with a 5kv
>> tester. I wondered why it took several seconds to reach the 5kv. When
>> he shorted it with a screwdriver it blew the end off the steel
>> screwdriver and bits of flying molten solder went everywhere.
>
> Most microwave capacitors have built in 15Meg resistor and discharge 
> pretty quickly, in minutes...


Phew.

Wish I could have read this when I had to change the table motor on our 
Bosch.  I was pretty careful because of the radiation situation and not 
wanting to render the equipment dangerous in that way, but I hadn't 
appreciated how long the capacitors may have remained charged!  (Though 
there are high voltage warning signs around them so care was indicated.)

One interesting feature of the oven, - which came apart satisfyingly 
easily - was the half punched out plate in the casing below the motor. 
Indicating it had been expected to fail, so they had thoughtfully provided 
the knock out to speed up the replacement!  Why they could not have simply 
left a hole and saved a bit on the metal is something of a mystery. The 
blanked out bit makes an interesting tea cup coaster though.

Incidentally, the fan and it's guard are quite tricky to get into a position 
that does not rattle now and again.  I can live with that.

S

In message 
, 
claudia.towner@googlemail.com writes
>Shouldn't be - they only radiate when powered up. As with any
>electrical equipment be wary of the capacitors which may still hold
>charge, even long after the equipment has been powered down. The
>capacitors in microwaves are particular high capacity. In my
>microwave, there is a huge red warning sticker attached to the
>capacitors to make this clear, but yours may not have this. If you
>have any doubts about what a component is, don't touch it!
>
>dan.
Bad, bad, bad. If you have no idea of the safety implications of opening 
a microwave, don't do it. It is highly likely to kill you if you touch 
the wrong bit inside and it can kill you weeks after you unplug it given 
certain fault conditions (that wouldn't necessarily affect normal 
operation). I believe the newer inverter ones are safer but even so...

Unless it's something really special, leave well alone or buy another 
one and if it is something really special then get someone who knows how 
to service it safely to do it.

-- 
Clint Sharp

On 2008-07-18 10:11:46 +0100, Huge <Huge@nowhere.much.invalid> said:

> On 2008-07-18, Andy Hall <andyh@hall.nospam> wrote:
>> On 2008-07-17 16:22:46 +0100, Huge <Huge@nowhere.much.invalid> said:
>> 
>>> On 2008-07-17, Andy Dingley  wrote:
>>>> On 17 Jul, 11:40, Andy Cap  wrote:
> 
> 
>>>> Web searching the Tesla Coil and Jacob's Ladder building sites will
>>>> suggest much about what to do with the innards of a microwave.
>>> 
>>> SIDE!
>> 
>> Switch Off
>> Isolate
>> Dump
>> Earth
> 
> Give that man a cee-gar.
> 
>> I remember seeing a short documentary
> 
> Wasn't it one of those day-time fill-in programs that existed before Jeremy
> Kyle?

I'm not sure who Jeremy Kyle is.

However, I did remember where I saw this film first.     It dates back 
to the 1960s and was used for BBC2 monochrome test transmissions prior 
to its launch in 1964.

About ten years later, I worked with a guy (sadly no longer with us) 
who had not long earlier co-invented some of the very first digital TV 
standards conversion equipment when he was at the IBA (as was).     
They used this film, plus another one which was a travelogue about 
Tunbridge Wells and had several long panning shots across tiled roofs.  
 The flashes in the SIDE one were very good for testing recovery of the 
picture after a sudden massive overexposure on the film, while the 
tiles tested how well the conversion equipment could keep up with 
massive detail movement.   In the end, the return didn't come so much 
from that functionality because sales volumes were not that high, but 
when the technology was used in broadcast video effects equipment.

On Jul 18, 7:04 am, Matty F  wrote:
> On Jul 18, 3:34 pm, meow2...@care2.com wrote:
>
> > That capacitor is the biggest safety deal in nukes. Advice to leave it
> > 24hrs does not inspire confidence, if the discharge resistor is o/c
> > chances are it can still kill you after a week. Avoiding the cap
> > doesnt work, the wires will conduct the lethal charge around the
> > place. Only safe option is to discharge it before getting in there.
> > Attach a wire from cooker case to screwdriver shaft, and use the blade
> > to touch _both_ cap terminals _together_. Screwdriver must be
> > insulated and hands kept away from bare shaft. People have died
> > servicing nukes.
>
> If the capacitor is that big, you'd better put safety goggles on
> before shorting it with a screwdriver. Better to use a resistance. My
> boss who should have known better, tested a large capacitor with a 5kv
> tester. I wondered why it took several seconds to reach the 5kv. When
> he shorted it with a screwdriver it blew the end off the steel
> screwdriver and bits of flying molten solder went everywhere.


Its only a couple of uF, but its enough to kill several people.


NT

On 2008-07-18, Andy Hall <andyh@hall.nospam> wrote:
> On 2008-07-18 10:11:46 +0100, Huge <Huge@nowhere.much.invalid> said:
>
>> On 2008-07-18, Andy Hall <andyh@hall.nospam> wrote:
>>> On 2008-07-17 16:22:46 +0100, Huge <Huge@nowhere.much.invalid> said:
>>> 
>>>> On 2008-07-17, Andy Dingley  wrote:
>>>>> On 17 Jul, 11:40, Andy Cap  wrote:
>> 
>> 
>>>>> Web searching the Tesla Coil and Jacob's Ladder building sites will
>>>>> suggest much about what to do with the innards of a microwave.
>>>> 
>>>> SIDE!
>>> 
>>> Switch Off
>>> Isolate
>>> Dump
>>> Earth
>> 
>> Give that man a cee-gar.
>> 
>>> I remember seeing a short documentary
>> 
>> Wasn't it one of those day-time fill-in programs that existed before Jeremy
>> Kyle?
>
> I'm not sure who Jeremy Kyle is.

You lucky man. Presenter of an appalling day-time TV show (which I might add,
I've only ever seen about 10 seconds of in total) which may as well be subtitled
"My mother is my sister and my Dad's run off with my brother. Can I get
compensation?"

> However, I did remember where I saw this film first.     It dates back 
> to the 1960s and was used for BBC2 monochrome test transmissions prior 
> to its launch in 1964.

I vaguely recall seeing it when I was off sick from school, but I was too young
for school in 1964. Could it have been shown later?


-- 
          "Be thankful that you have a life, and forsake your vain
                 and presumptuous desire for a second one."
               [email me at huge {at} huge (dot) org <dot> uk]

On 2008-07-19 10:04:55 +0100, Huge <Huge@nowhere.much.invalid> said:

> On 2008-07-18, Andy Hall <andyh@hall.nospam> wrote:
>> On 2008-07-18 10:11:46 +0100, Huge <Huge@nowhere.much.invalid> said:
>> 
>>> On 2008-07-18, Andy Hall <andyh@hall.nospam> wrote:
>>>> On 2008-07-17 16:22:46 +0100, Huge <Huge@nowhere.much.invalid> said:
>>>> 
>>>>> On 2008-07-17, Andy Dingley  wrote:
>>>>>> On 17 Jul, 11:40, Andy Cap  wrote:
>>> 
>>> 
>>>>>> Web searching the Tesla Coil and Jacob's Ladder building sites will
>>>>>> suggest much about what to do with the innards of a microwave.
>>>>> 
>>>>> SIDE!
>>>> 
>>>> Switch Off
>>>> Isolate
>>>> Dump
>>>> Earth
>>> 
>>> Give that man a cee-gar.
>>> 
>>>> I remember seeing a short documentary
>>> 
>>> Wasn't it one of those day-time fill-in programs that existed before Jeremy
>>> Kyle?
>> 
>> I'm not sure who Jeremy Kyle is.
> 
> You lucky man. Presenter of an appalling day-time TV show (which I might add,
> I've only ever seen about 10 seconds of in total) which may as well be 
> subtitled
> "My mother is my sister and my Dad's run off with my brother. Can I get
> compensation?"

I really am pleased that I know nothing of this.



> 
>> However, I did remember where I saw this film first.     It dates back
>> to the 1960s and was used for BBC2 monochrome test transmissions prior
>> to its launch in 1964.
> 
> I vaguely recall seeing it when I was off sick from school, but I was too young
> for school in 1964. Could it have been shown later?

Could be.    I wonder if they used it for colour test transmissions 
later on.   However, that would only be three years because  they went 
into production scheduled colour in 1967.  Even so, I'm not sure that 
the SIDE film was in colour.    I remember the participants looked like 
stereotyped research scientists at a government centre complete with 
short back and sides haircuts, pens in the top pocket and those 
expanding bands that draughtsmen wear that go over shirt sleeves to 
keep cuffs out of the way

On Fri, 18 Jul 2008 14:17:33 +0100, "Spamlet" <spamlet@invalid.invalid>
wrote:

>Is there an easy way I could incorporate one of these into a squirrel trap 
>that currently only serves as a squirrel, free meal station?

You can buy it ready made  "Rat zapper" or somesuch.

"Andy Dingley"  wrote in message 
news:g0u3849v4f9rf56aki9q1513hg28uuqted@4ax.com...
> On Fri, 18 Jul 2008 14:17:33 +0100, "Spamlet" <spamlet@invalid.invalid>
> wrote:
>
>>Is there an easy way I could incorporate one of these into a squirrel trap
>>that currently only serves as a squirrel, free meal station?
>
> You can buy it ready made  "Rat zapper" or somesuch.

So you can!

Now how do I make just the squirrels go in there?

(I have redesigned my 'live squirrel cage trap. What must be dozens of times 
now.  However clever I think  I have been the buggers always suss it out 
first go; in the dark!  All I managed to catch were the young ones and the 
odd mouse: the culprits just sit on the fence laughing, and waiting for the 
next freebie.)

Cheers for the tip.

S

wrote in message 
news:13dfc177-9654-4f8e-8b17-d68ce50a0cdc@m45g2000hsb.googlegroups.com...
On Jul 18, 7:04 am, Matty F  wrote:
> On Jul 18, 3:34 pm, meow2...@care2.com wrote:
>
> > That capacitor is the biggest safety deal in nukes. Advice to leave it
> > 24hrs does not inspire confidence, if the discharge resistor is o/c
> > chances are it can still kill you after a week. Avoiding the cap
> > doesnt work, the wires will conduct the lethal charge around the
> > place. Only safe option is to discharge it before getting in there.
> > Attach a wire from cooker case to screwdriver shaft, and use the blade
> > to touch _both_ cap terminals _together_. Screwdriver must be
> > insulated and hands kept away from bare shaft. People have died
> > servicing nukes.
>
> If the capacitor is that big, you'd better put safety goggles on
> before shorting it with a screwdriver. Better to use a resistance. My
> boss who should have known better, tested a large capacitor with a 5kv
> tester. I wondered why it took several seconds to reach the 5kv. When
> he shorted it with a screwdriver it blew the end off the steel
> screwdriver and bits of flying molten solder went everywhere.


Its only a couple of uF, but its enough to kill several people.


NT

How does that compare with tazers?

S

On Sat, 19 Jul 2008 17:44:02 +0100, "Spamlet" <spamlet@invalid.invalid>
wrote:

>How does that compare with tazers?

Tasers are higher voltage, but lower capacity and much lower potential
for a current.  HT in the home is normally found in low-power devices
like TVs, flashguns (and "home-radar" garage door openers, if you root
in the same skips I do). If you take a zap from that, it's painful and
the muscle spasm may cause you to leap through a glass door or off a
ladder, or somethign similarly injurious, but it's _unlikely_ to kill
you outright.   

A microwave oven OTOH is a high power transmitter. Seriously high-power.
So its PSU works with a seriously high power (and thus high current),
even at these voltages. It'll have a damned good go at killing you.

-- 
 Cats have nine lives, which is why they rarely post to Usenet.

Andy Hall wrote:

> Could be.    I wonder if they used it for colour test transmissions 
> later on.   However, that would only be three years because  they went 
> into production scheduled colour in 1967.  Even so, I'm not sure that 
> the SIDE film was in colour.

Yes, it was one of the trade test colour films:

   ON THE SAFE SIDE
   An Atomic Energy Association Film (U.K.A.E.A.)
   18 minutes duration
   First showing 1st May 1968
   Final showing 17th July 1973
   A film showing safety precautions undertaken in a UK power station.
   Made In 1967.
[Info from http://www.bvws.org.uk/405alive/info/prog_tradefilms.html]

For power station above read high-voltage test lab, I's say.

More nostalgia at
http://www.zen77094.zen.co.uk/vintagebroadcasting/bbcttfilms.htm

-- 
Andy

On 2008-07-19 23:30:55 +0100, Andy Wade  said:

> Andy Hall wrote:
> 
>> Could be.    I wonder if they used it for colour test transmissions 
>> later on.   However, that would only be three years because  they went 
>> into production scheduled colour in 1967.  Even so, I'm not sure that 
>> the SIDE film was in colour.
> 
> Yes, it was one of the trade test colour films:
> 
>    ON THE SAFE SIDE
>    An Atomic Energy Association Film (U.K.A.E.A.)
>    18 minutes duration
>    First showing 1st May 1968
>    Final showing 17th July 1973
>    A film showing safety precautions undertaken in a UK power station.
>    Made In 1967.
> [Info from http://www.bvws.org.uk/405alive/info/prog_tradefilms.html]
> 
> For power station above read high-voltage test lab, I's say.
> 
> More nostalgia at
> http://www.zen77094.zen.co.uk/vintagebroadcasting/bbcttfilms.htm

That's the one and the later date than I thought probably explains how 
the young Huge remembers it.

On 2008-07-19, Andy Wade  wrote:
> Andy Hall wrote:
>
>> Could be.    I wonder if they used it for colour test transmissions 
>> later on.   However, that would only be three years because  they went 
>> into production scheduled colour in 1967.  Even so, I'm not sure that 
>> the SIDE film was in colour.
>
> Yes, it was one of the trade test colour films:
>
>    ON THE SAFE SIDE
>    An Atomic Energy Association Film (U.K.A.E.A.)
>    18 minutes duration
>    First showing 1st May 1968
>    Final showing 17th July 1973
>    A film showing safety precautions undertaken in a UK power station.
>    Made In 1967.
> [Info from http://www.bvws.org.uk/405alive/info/prog_tradefilms.html]

Aha. Thank you!


-- 
          "Be thankful that you have a life, and forsake your vain
                 and presumptuous desire for a second one."
               [email me at huge {at} huge (dot) org <dot> uk]

Andy Hall <andyh@hall.nospam> wrote:

> That's the one and the later date than I thought probably explains how
> the young Huge remembers it.

Never seen it, but it was broadcast during period when I wrote "TV
watching causes cancer of the eyeballs" on demands that wanted to know
why I didn't have a TV licence.

It seems that nowadays that films made with similar intent are shown at
2AM - 5AM and that daytime TV consists of chavs "emoting" about their
relationship problems, which most of them wouldn't have if they could
communicate rather than grunt, whine and scream abuse.

On Sun, 20 Jul 2008 11:41:56 +0100, %steve%@malloc.co.uk (Steve Firth)
wrote:

>It seems that nowadays that films made with similar intent are shown at
>2AM - 5AM and that daytime TV consists of chavs "emoting" about their
>relationship problems, which most of them wouldn't have if they could
>communicate rather than grunt, whine and scream abuse.

Ah Steve, how is life in Tunbridge Wells?

Andy Dingley  wrote:

> On Sun, 20 Jul 2008 11:41:56 +0100, %steve%@malloc.co.uk (Steve Firth)
> wrote:
> 
> >It seems that nowadays that films made with similar intent are shown at
> >2AM - 5AM and that daytime TV consists of chavs "emoting" about their
> >relationship problems, which most of them wouldn't have if they could
> >communicate rather than grunt, whine and scream abuse.
> 
> Ah Steve, how is life in Tunbridge Wells?

I wouldn't know, I have no desire to live in chav central.

"Andy Hall" <andyh@hall.nospam> wrote in message news:48826cc1@qaanaaq...
> On 2008-07-19 23:30:55 +0100, Andy Wade  
> said:
>
>> Andy Hall wrote:
>>
>>> Could be.    I wonder if they used it for colour test transmissions 
>>> later on.   However, that would only be three years because  they went 
>>> into production scheduled colour in 1967.  Even so, I'm not sure that 
>>> the SIDE film was in colour.
>>
>> Yes, it was one of the trade test colour films:
>>
>>    ON THE SAFE SIDE
>>    An Atomic Energy Association Film (U.K.A.E.A.)
>>    18 minutes duration
>>    First showing 1st May 1968
>>    Final showing 17th July 1973
>>    A film showing safety precautions undertaken in a UK power station.
>>    Made In 1967.
>> [Info from http://www.bvws.org.uk/405alive/info/prog_tradefilms.html]
>>
>> For power station above read high-voltage test lab, I's say.
>>
>> More nostalgia at
>> http://www.zen77094.zen.co.uk/vintagebroadcasting/bbcttfilms.htm
>
> That's the one and the later date than I thought probably explains how the 
> young Huge remembers it.
>
>
>
Brilliant - brought back memories of an old Dynatron with a hinge up panel 
wit 27 convergence controls.

Steve Firth wrote:

> 
> I wouldn't know, I have no desire to live in chav central.


Blimey, the chavs round your way must be incredibly affluent if they can 
afford to live in TW.

Richard ;-)

Richard  wrote:

> Steve Firth wrote:
> 
> > 
> > I wouldn't know, I have no desire to live in chav central.
> 
> 
> Blimey, the chavs round your way must be incredibly affluent if they can
> afford to live in TW.

Even the chavs around my way would consider TW as beneath them. It is in
Kent, which runs in second place to Essex as Chavheim. FFS they can't
even speak English there.

> Richard ;-)

Steve :-P

On 21 Jul, 23:15, %ste...@malloc.co.uk (Steve Firth) wrote:
> Richard  wrote:
> > Steve Firth wrote:
>
> > > I wouldn't know, I have no desire to live in chav central.
>
> > Blimey, the chavs round your way must be incredibly affluent if they can
> > afford to live in TW.
>
> Even the chavs around my way would consider TW as beneath them. It is in
> Kent, which runs in second place to Essex as Chavheim. FFS they can't
> even speak English there.
>
> > Richard ;-)
>
> Steve :-P

Talking out of your backside, mate!!!

The OFFICIAL (look it up)  capital of Chavism is Gornal, near Dudley,
West Midlands where 87% of the population under 27 is a chav.... and
77% of the population over 27....

On 22 Jul, 14:55, The Crimson King  wrote:

> The OFFICIAL (look it up)  capital of Chavism is Gornal, near Dudley,

Who says?  Is there an OfChav now?

> West Midlands where 87% of the population under 27 is a chav.... and
> 77% of the population over 27....

You mean, 164% of the peopleation is chavs, innit.

The Crimson King  wrote:

> On 21 Jul, 23:15, %ste...@malloc.co.uk (Steve Firth) wrote:
> > Richard  wrote:
> > > Steve Firth wrote:
> >
> > > > I wouldn't know, I have no desire to live in chav central.
> >
> > > Blimey, the chavs round your way must be incredibly affluent if they can
> > > afford to live in TW.
> >
> > Even the chavs around my way would consider TW as beneath them. It is in
> > Kent, which runs in second place to Essex as Chavheim. FFS they can't
> > even speak English there.
> >
> > > Richard ;-)
> >
> > Steve :-P
> 
> Talking out of your backside, mate!!!

Ah, a Kentchav stands up to be counted.

On Jul 17, 2:19 pm, Andy Cap  wrote:
> On Thu, 17 Jul 2008 17:11:26 퍝, Harry Bloomfield
>
>  wrote:
> >Andy Cap used his keyboard to write :
> >> Hi
>
> >> Is there any problem with investigating the internal of a microwave oven ?
> >> Not turning it on of course.
>
> >> Mine has developed an intermittent rattle, which stops if you press on the
> >> case side and I suspect it is just something slightly loose but I have no
> >> means of testing it, once the case is replaced or should I just bin it> >The capacitors inside can store a couple of thousand volts for quite a
> >long time. They are supposed to be fitted with a high value resistor to
> >discharge them, but that can go faulty. Best to make sure these are
> >discharged before probing about inside.
>
> Thanks to everyone who's warned of the dangers. I will take a careful look over
> the next few days.
>
> Andy
Not too much wrong with all this advice, BUT:
Be careful.
Very careful!
Microwave ovens sometimes described as 'One of the most dangerous
domestic appliances ever made'.
Reasons:
1) They are essentially a one thousand watt (or thereabouts) radio
transmitter inside a box**. That's why there are essential safety door
switches, and checking for unwanted radiation/leakage can be
important. If it can cook a piece of steak in minutes etc. it can fry
your hand, or worse, your eyeballs, and or some internal organ. So do
not operate when it's open.
Also make sure it goes back together properly when the cover is
replaced, there are sometimes RF sealing devices on the edges and
overlaps of the various panels. Tricky to get right sometimes; but
essential!
2) Yes; there are dangerous voltages and the capacitor/s can store
some of those as others have described. The transformer can typically
provided 2000 RMS, volts which is then voltage doubled by a rectifier-
capacitor to a peak of sometimes over 5000 volts.
Strongly recommend that unless one is an experienced electronics,
preferably one with radio transmitter training, technician be
EXTREMELY careful.
Or leave it alone. The cost of a microwave oven these days does not
warrant IMO the risks of fiddling with something that costs well under
$100! Recently a local 'big store' here had stainless steel smallish
m.waves on sale for around $50 Canadian (About 25 quid!) And it wasn't
an 'In store' or 'Manager's' special to get rid of stock. It was a
national price in their printed circular! Have fixed quite a few units
using background as communications technician/manager of some 40
years. But although being a fix-it junky in this throwaway society do
urge everyone to be extra careful; not only fixing them but also using
them and having children and pets around where they are operating.
BTW as a cruel experiment put a wasp (large fly etc.) or other deemed
undesirable insect in a microwave in a glass jar; switch on and it
will die in seconds!
Note: Radio amateurs can transmit around the world using 150 watts;
one sixth the output of a microwave oven and if one thinks of say a
1000 watt electric fry pan or electric hot plate ...................
well you wouldn't put your hands or head close to that; would you? Or
rather like putting 10  100 watt light bulbs inside a box and then
wondering why things got hot!!!!!