Hi all,

I have had the same Daewoo microwave oven since I bought it new 7 years
ago and it's always performed *perfectly* up until today. This morning I
stuck some bread in it to defrost and it came out still frozen. No trace
of any heat at all. The platter rotates, the light comes on, the timer
counts down, the fan runs; all is working fine except for the total
absence of heat.
I'm given to understand that microwave ovens typically have a working
life of only around 2 years nowadays, so I'd really like to fix this one
up rather than replace it with something inevitably inferior. Any
suggestions as to what to check for? I have the gear to measure up to
50kV if necessary, and I'd guess the magnetron HT is considerably less
than that figure. So... where to start looking first?



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On Friday, 22 March 2019 19:37:05 UTC, Cursitor Doom wrote:
Hi all,

I have had the same Daewoo microwave oven since I bought it new 7 years
ago and it's always performed *perfectly* up until today. This morning I
stuck some bread in it to defrost and it came out still frozen. No trace
of any heat at all. The platter rotates, the light comes on, the timer
counts down, the fan runs; all is working fine except for the total
absence of heat.
I'm given to understand that microwave ovens typically have a working
life of only around 2 years nowadays, so I'd really like to fix this one
up rather than replace it with something inevitably inferior. Any
suggestions as to what to check for? I have the gear to measure up to
50kV if necessary, and I'd guess the magnetron HT is considerably less
than that figure. So... where to start looking first?

Likely candidates are the HV diode & HV fuse. Of course it can be other things. And of course they're in the killer section.


NT

On Friday, March 22, 2019 at 3:37:05 PM UTC-4, Cursitor Doom wrote:
Hi all,

I have had the same Daewoo microwave oven since I bought it new 7 years
ago and it's always performed *perfectly* up until today. This morning I
stuck some bread in it to defrost and it came out still frozen. No trace
of any heat at all. The platter rotates, the light comes on, the timer
counts down, the fan runs; all is working fine except for the total
absence of heat.
I'm given to understand that microwave ovens typically have a working
life of only around 2 years nowadays, so I'd really like to fix this one
up rather than replace it with something inevitably inferior. Any
suggestions as to what to check for? I have the gear to measure up to
50kV if necessary, and I'd guess the magnetron HT is considerably less
than that figure. So... where to start looking first?


The easy place to start is with the door switches. Microwaves usually have several as a fail safe.

With the microwave running, watch the interior light carefully and listen for any change in sound as you slowly rock the door. If the light dims and you hear a buzz begin, you've got a cranky safety interlock switch. There could be a broken activator tang as well and it might be visible right on the door.

Inside, the relays are known to develop cracks in the solder at the pc board, so leaning on the relay and edge connectors could restart the cooking.

On Fri, 22 Mar 2019 14:18:03 -0700, tabbypurr wrote:

Likely candidates are the HV diode & HV fuse. Of course it can be other
things. And of course they're in the killer section.


Familiar territory then. I've spent god knows how many years prodding
around inside the HT cages of CROs and whatnot.





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On Friday, 22 March 2019 21:46:47 UTC, Cursitor Doom wrote:
On Fri, 22 Mar 2019 14:18:03 -0700, tabbypurr wrote:

Likely candidates are the HV diode & HV fuse. Of course it can be other
things. And of course they're in the killer section.


Familiar territory then. I've spent god knows how many years prodding
around inside the HT cages of CROs and whatnot.

That's good.

Re interlocks, they're designed to short out via a power resistor if any one fails to operate correctly. So usually interlock failure results in an oc shorting resistor - which is a hazardous state in which to run a nuke. So it's always worth checking continuity of the big resistor when you have the cover off. IME interlocks are low on the list of likely suspects.


NT

On Fri, 22 Mar 2019 19:37:03 -0000 (UTC), Cursitor
Doom wrote:

Hi all,

I have had the same Daewoo microwave oven since I bought it new 7 years
ago and it's always performed *perfectly* up until today. This morning I
stuck some bread in it to defrost and it came out still frozen. No trace
of any heat at all. The platter rotates, the light comes on, the timer
counts down, the fan runs; all is working fine except for the total
absence of heat.
I'm given to understand that microwave ovens typically have a working
life of only around 2 years nowadays, so I'd really like to fix this one
up rather than replace it with something inevitably inferior. Any
suggestions as to what to check for? I have the gear to measure up to
50kV if necessary, and I'd guess the magnetron HT is considerably less
than that figure. So... where to start looking first?

Replacing the lamp has me defeated. I buy a new
mwave then.

On Sat, 23 Mar 2019 10:09:02 +1100, Peter Jason wrote:

Replacing the lamp has me defeated. I buy a new mwave then.

I don't want a new one, though! The existing one is built to an amazingly
high standard and the manufacturer has taken time and trouble to finish
it beautifully as well. I'll struggle to find anything around today that
comes close to that quality.



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On Friday, March 22, 2019 at 9:02:12 PM UTC-4, Cursitor Doom wrote:
On Sat, 23 Mar 2019 10:09:02 +1100, Peter Jason wrote:

Replacing the lamp has me defeated. I buy a new mwave then.

I don't want a new one, though! The existing one is built to an amazingly
high standard and the manufacturer has taken time and trouble to finish
it beautifully as well. I'll struggle to find anything around today that
comes close to that quality.



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Most of the tests can be done with the power off (continuity checks)...to summarize:
Ck door switches
Ck power resistor
Ck HV diode
Ck magnetron
Ck HV transformer

I won't repeat/elaborate on these but here is some detailed diagnostic techniques.
https://www.partselect.com/Repair/Microwave/No-Heat/

Ebay is a source of parts, especially magnetrons at reasonable prices. You will see the name Galant as a mfg. The produce something like 70% of the worlds magnetrons and they sell to everybody (panasonic, toshiba, daewoo, etc, etc.
Most of the others are low quality knockoffs...YMMV

You should search online for a schematic for your unit...all will become clear with that in hand. Fairly simple.
J

On Saturday, 23 March 2019 17:15:49 UTC, wrote:
On Friday, March 22, 2019 at 9:02:12 PM UTC-4, Cursitor Doom wrote:
On Sat, 23 Mar 2019 10:09:02 +1100, Peter Jason wrote:

Replacing the lamp has me defeated. I buy a new mwave then.

I don't want a new one, though! The existing one is built to an amazingly
high standard and the manufacturer has taken time and trouble to finish
it beautifully as well. I'll struggle to find anything around today that
comes close to that quality.

Most of the tests can be done with the power off (continuity checks)...to summarize:
Ck door switches
Ck power resistor
Ck HV diode
Ck magnetron
Ck HV transformer

I won't repeat/elaborate on these but here is some detailed diagnostic techniques.
https://www.partselect.com/Repair/Microwave/No-Heat/

Ebay is a source of parts, especially magnetrons at reasonable prices. You will see the name Galant as a mfg. The produce something like 70% of the worlds magnetrons and they sell to everybody (panasonic, toshiba, daewoo, etc, etc.
Most of the others are low quality knockoffs...YMMV

You should search online for a schematic for your unit...all will become clear with that in hand. Fairly simple.
J

If it's mechanical control, the circuit is much the same for them all. And the cct is usually printed inside the outer cover. Why they're the one appliance to have that I don't know.


NT

On Fri, 22 Mar 2019 19:37:03 -0000 (UTC), Cursitor Doom
wrote:

Hi all,

I have had the same Daewoo microwave oven since I bought it new 7 years
ago and it's always performed *perfectly* up until today. This morning I
stuck some bread in it to defrost and it came out still frozen. No trace
of any heat at all. The platter rotates, the light comes on, the timer
counts down, the fan runs; all is working fine except for the total
absence of heat.
I'm given to understand that microwave ovens typically have a working
life of only around 2 years nowadays, so I'd really like to fix this one
up rather than replace it with something inevitably inferior. Any
suggestions as to what to check for? I have the gear to measure up to
50kV if necessary, and I'd guess the magnetron HT is considerably less
than that figure. So... where to start looking first?

Sometimes the relays go intermittent. Try tapping them with an
insulated probe if it isn't door switches, themal cut-off sensor,
filament connections, HV diode or capacitor.

Cursitor Doom wrote:


Likely candidates are the HV diode & HV fuse. Of course it can be other
things. And of course they're in the killer section.


Familiar territory then.


** Massive false assumption.


I've spent god knows how many years prodding
around inside the HT cages of CROs and whatnot.



** There is no comparison - microwave ovens are highly lethal to repairers, hundreds of times more so than scopes.

Never play down the risk, that would be a criminal thing to do.




..... Phil




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On Saturday, 23 March 2019 21:22:36 UTC, Phil Allison wrote:
Cursitor Doom wrote:

Likely candidates are the HV diode & HV fuse. Of course it can be other
things. And of course they're in the killer section.


Familiar territory then.


** Massive false assumption.


I've spent god knows how many years prodding
around inside the HT cages of CROs and whatnot.



** There is no comparison - microwave ovens are highly lethal to repairers, hundreds of times more so than scopes.

but the techniques for dealing with EHT are the same. He's an electrical guy with experience with EHT, not a random newb.


Never play down the risk, that would be a criminal thing to do.

did anyone? No.

tabb...is a dangerous MORON



Phil Allison wrote:
Cursitor Doom wrote:

Likely candidates are the HV diode & HV fuse. Of course it can be other
things. And of course they're in the killer section.


Familiar territory then.


** Massive false assumption.


I've spent god knows how many years prodding
around inside the HT cages of CROs and whatnot.



** There is no comparison - microwave ovens are highly lethal
to repairers, hundreds of times more so than scopes.

but the techniques for dealing with EHT are the same.


** That is another dangerous false assumption.


He's an electrical guy with experience with EHT,


** More likely to make him careless with a microwave oven.


not a random newb.


** Yawnnnn....



Never play down the risk, that would be a criminal thing to do.

did anyone?


** Well, you just did and so did he.

But having wanked yourselves bind you cannot read your own posts.


No.

** Complete ****wits like you and CD need a giant kick up the arse.

I could not give a **** about either of you being electrocuted - but there are others who read these pages and they are not so deserving.



..... Phil

On Saturday, 23 March 2019 22:19:12 UTC, Phil Allison wrote:
tabb...is a dangerous MORON
Phil Allison wrote:
Cursitor Doom wrote:

Likely candidates are the HV diode & HV fuse. Of course it can be other
things. And of course they're in the killer section.


Familiar territory then.


** Massive false assumption.


I've spent god knows how many years prodding
around inside the HT cages of CROs and whatnot.



** There is no comparison - microwave ovens are highly lethal
to repairers, hundreds of times more so than scopes.

but the techniques for dealing with EHT are the same.


** That is another dangerous false assumption.


He's an electrical guy with experience with EHT,


** More likely to make him careless with a microwave oven.


not a random newb.


** Yawnnnn....



Never play down the risk, that would be a criminal thing to do.

did anyone?


** Well, you just did and so did he.

But having wanked yourselves bind you cannot read your own posts.


No.

** Complete ****wits like you and CD need a giant kick up the arse.

I could not give a **** about either of you being electrocuted - but there are others who read these pages and they are not so deserving.



.... Phil

I'm pretty sure how I approach it is safe, but enjoy your trip.

On Sat, 23 Mar 2019 17:16:57 -0700, tabbypurr wrote:


I'm pretty sure how I approach it is safe, but enjoy your trip.

Phil would probably like to see me and several other posters here dead if
the truth be known. There is so much hatred in that man. Fortunately,
since I perma-plonked him some time ago I rarely have to see his so-
called "contributions" any more.
I could accept Phil's attitude problem if he gave 100% accurate advice,
I'd happily ignore all the bile as a personality quirk, but he's
frequently wrong and when that's pointed out to him he invariably attacks
whoever exposed it in the most visceral way. I struggle to see how
personal attacks are going to improve his credibility, but if that's what
he believes there's nothing you or I or anyone else can do about it.





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On Sat, 23 Mar 2019 10:15:46 -0700, jjhudak4 wrote:

Most of the tests can be done with the power off (continuity
checks)...to summarize:
Ck door switches Ck power resistor Ck HV diode Ck magnetron Ck HV
transformer

I won't repeat/elaborate on these but here is some detailed diagnostic
techniques.
https://www.partselect.com/Repair/Microwave/No-Heat/

Ebay is a source of parts, especially magnetrons at reasonable prices.
You will see the name Galant as a mfg. The produce something like 70%
of the worlds magnetrons and they sell to everybody (panasonic, toshiba,
daewoo, etc, etc.
Most of the others are low quality knockoffs...YMMV

You should search online for a schematic for your unit...all will become
clear with that in hand. Fairly simple.

Many thanks for that info. This is also worth a look:

https://tinyurl.com/y4gh8cdb




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On 23/03/2019 6:37 am, Cursitor Doom wrote:
Hi all,

I have had the same Daewoo microwave oven since I bought it new 7 years
ago and it's always performed *perfectly* up until today. This morning I
stuck some bread in it to defrost and it came out still frozen. No trace
of any heat at all. The platter rotates, the light comes on, the timer
counts down, the fan runs; all is working fine except for the total
absence of heat.
I'm given to understand that microwave ovens typically have a working
life of only around 2 years nowadays, so I'd really like to fix this one
up rather than replace it with something inevitably inferior. Any
suggestions as to what to check for? I have the gear to measure up to
50kV if necessary, and I'd guess the magnetron HT is considerably less
than that figure. So... where to start looking first?



**First off: As Phil has stated, these things are VERY dangerous.
NOTHING like working on the EHT of a TV set (which certainly can bite).
2kV+ of DC WILL kill. No doubt about it.

Next: If it has a big ole' transformer (easy to tell, if you need two
hands to carry it), it should be an easy fix. Diode or magnetron. Most
likely the magnetron, though they usually fail slowly, due to emission
loss. It could be something else though.

Lastly: If it employs an SMPS, rather than a big lump of iron and
copper, dump it and buy a new one. Not worth the effort.


--
Trevor Wilson
www.rageaudio.com.au

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Cursitor Doom wrote:



Phil would probably like to see me and several other posters here dead if
the truth be known.



** Just all the trolls - like you.



There is so much hatred in that man.

** Yep - I hate trolls.

They ruin newsgroups for everyone.


Fortunately,
since I perma-plonked him some time ago


** What a gutless waste of space you are.


I could accept Phil's attitude problem if he gave 100% accurate advice,


** No such thing is possible or required of anyone here.

You are completely insane.


I'd happily ignore all the bile as a personality quirk, but he's
frequently wrong


** FFS prove it - not once have you ever done that.

You lying pile of ****.



...... Phil

On Mon, 25 Mar 2019 04:38:56 +1100, Trevor Wilson wrote:

**First off: As Phil has stated, these things are VERY dangerous.
NOTHING like working on the EHT of a TV set (which certainly can bite).
2kV+ of DC WILL kill. No doubt about it.

*CAN* kill. *Not* WILL. Depends on *several* factors so your "no doubt
about it" is incorrect.
There is one large fat potentially-lethal capacitor in there that needs
to be discharged as the first job to do after the removal of the outer
casing. It doesn't appear to have a bleed resistor for some reason (not
with this particular oven anyway.)





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On Sunday, 24 March 2019 14:26:10 UTC, Cursitor Doom wrote:
On Sat, 23 Mar 2019 17:16:57 -0700, tabbypurr wrote:


I'm pretty sure how I approach it is safe, but enjoy your trip.

Phil would probably like to see me and several other posters here dead if
the truth be known.

I don't doubt it.

There is so much hatred in that man. Fortunately,
since I perma-plonked him some time ago I rarely have to see his so-
called "contributions" any more.
I could accept Phil's attitude problem if he gave 100% accurate advice,
I'd happily ignore all the bile as a personality quirk, but he's
frequently wrong and when that's pointed out to him he invariably attacks
whoever exposed it in the most visceral way.

Yup

I struggle to see how
personal attacks are going to improve his credibility, but if that's what
he believes there's nothing you or I or anyone else can do about it.

It would be sensible to say microwaves can electrocute people, not so sensible to insist everyone, despite not knowing what skills they do or don't have, does not have the necessary skills to work with them. It's not difficult, just need to know the issues/gotchas. There's EHT, soakage, leakage, and the principles of the interlock system. Otherwise it's just more electrical equipment, with its design quirks like the transformer.


NT

Criminal troll wrote:



It would be sensible to say microwaves can electrocute people,


** Idiotic to say otherwise - you fool.


not so sensible to insist everyone, despite not knowing what skills they do or don't have, does not have the necessary skills to work with them.


** Insane crap.

You must KNOW the person has the knowledge, skill and necessary safety gear on hand. Plus they must not work alone.

Impossible to ascertain that via usenet so the only safe option is to advise against and offer no help.


It's not difficult, just need to know the issues/gotchas.


** Totally insane crap.

One needs to be trained on the proper precautions with microwaves ovens and USE them.

You are one dangerous ****ing idiot.
----------------------------------



...... Phil

On Monday, 25 March 2019 01:13:16 UTC, Phil Allison wrote:
Criminal troll tabby wrote:



It would be sensible to say microwaves can electrocute people,


** Idiotic to say otherwise - you fool.

so we get abuse for agreeing with you lol


not so sensible to insist everyone, despite not knowing what skills they do or don't have, does not have the necessary skills to work with them.

** Insane crap.

You must KNOW the person has the knowledge, skill and necessary safety gear on hand. Plus they must not work alone.

Neither I nor you need know what skill Mr Doom has.


Impossible to ascertain that via usenet so the only safe option is to advise against and offer no help.

There are people taking that tack on any subject. Thankfully some are more constructive.


It's not difficult, just need to know the issues/gotchas.

** Totally insane crap.

One needs to be trained on the proper precautions with microwaves ovens and USE them.

If you understand the gotchas & are sensible you're going to use them. We can't do more than that on usenet.


You are one dangerous ****ing idiot.

With respect you don't know what my working practices are with microwaves, which makes your statement a bit silly.


NT

On Mon, 25 Mar 2019 05:06:04 -0700, tabbypurr wrote:

With respect you don't know what my working practices are with
microwaves, which makes your statement a bit silly.


See, you politely disagree with him and all you get in response is a load
of foul-mouthed abuse. As if that's really going to win people over! :-D




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On Mon, 25 Mar 2019 05:06:04 -0700, tabbypurr wrote:

On Monday, 25 March 2019 01:13:16 UTC, Phil Allison wrote:

Impossible to ascertain that via usenet so the only safe option is to
advise against and offer no help.

There are people taking that tack on any subject. Thankfully some are
more constructive.

Funny, that. Phil has offered advice to all-comers over the years with
questions about how to fix mains-powered appliances which of course CAN
also kill if you don't know what you're doing. So there you have it: more
proof he doesn't even follow his *own* advice! :-D



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On Monday, March 25, 2019 at 11:29:52 AM UTC-4, Cursitor Doom wrote:
On Mon, 25 Mar 2019 05:06:04 -0700, tabbypurr wrote:

On Monday, 25 March 2019 01:13:16 UTC, Phil Allison wrote:

Impossible to ascertain that via usenet so the only safe option is to
advise against and offer no help.

There are people taking that tack on any subject. Thankfully some are
more constructive.

Funny, that. Phil has offered advice to all-comers over the years with
questions about how to fix mains-powered appliances which of course CAN
also kill if you don't know what you're doing. So there you have it: more
proof he doesn't even follow his *own* advice! :-D



The difference is everyone knows that mains inputs will kill, but most people are unaware of just how dangerous a microwave is compared to any other plug in appliance around the home.

"The U.S. Consumer Product Safety Commission reports that four people are electrocuted each year trying to repair their microwave ovens."

https://www.richmond.com/news/man-di...a1c3ff15a.html

On Fri, 22 Mar 2019 14:18:03 -0700, tabbypurr wrote:

Likely candidates are the HV diode & HV fuse. Of course it can be other
things. And of course they're in the killer section.

Spot on. Blown 5kV fuse and HV diode open circuit both directions.
Transformer secondary showing 188 ohms across the winding, so *hopefully*
a quick fix. But I'd better just check the magnetron first.......
:-/





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On 3/25/19 11:15 AM, John-Del wrote:

The difference is everyone knows that mains inputs will kill, but most people are unaware of just how dangerous a microwave is compared to any other plug in appliance around the home.

"The U.S. Consumer Product Safety Commission reports that four people are electrocuted each year trying to repair their microwave ovens."

https://www.richmond.com/news/man-di...a1c3ff15a.html


Ya-but.
How many people die from accidents with guns?
Drunk driving.
Trying to make "jack ass" videos for you tube?

Considering the number of microwave ovens out there,that's a
pretty low death rate.

The best advice you can give about working on micro wave ovens
is:
The voltages, and the components that use/store them are lethal.
In the words of Sgt. Phil from Hill Street Blues, "Let's be
careful out there."


--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com

On Monday, March 25, 2019 at 12:15:29 PM UTC-4, John-Del wrote:

The difference is everyone knows that mains inputs will kill, but most people are unaware of just how dangerous a microwave is compared to any other plug in appliance around the home.

"The U.S. Consumer Product Safety Commission reports that four people are electrocuted each year trying to repair their microwave ovens."

https://www.richmond.com/news/man-di...a1c3ff15a.html

Some opinions he

Tabby would try the patience of Job, and is no more right, nor wrong than Phil on a general basis. Which is damned with faint praise, if ever there were.

Phil, were he to behave "at home" as he does "away" on this group would be, rapidly, rendered incapacitated, probably on a permanent basis. There is some significant pathology going on there, rendering Phil a figure to be pitied.

I am as good with invective and vituperation as the next guy, here, and seldom find the need to use vulgarity. But, Phil is one sort of special case, being as that is all he has. And Tabby is another sort of special case, as he *must* find the exceptional case for everything. Which, at the very least, gets tiresome.

Peter Wieck
Melrose Park, PA

On Monday, March 25, 2019 at 12:38:49 PM UTC-4, Fox's Mercantile wrote:
On 3/25/19 11:15 AM, John-Del wrote:

The difference is everyone knows that mains inputs will kill, but most people are unaware of just how dangerous a microwave is compared to any other plug in appliance around the home.

"The U.S. Consumer Product Safety Commission reports that four people are electrocuted each year trying to repair their microwave ovens."

https://www.richmond.com/news/man-di...a1c3ff15a.html


Ya-but.
How many people die from accidents with guns?
Drunk driving.

In fairness, pretty much all guns are handled at some point, and a LOT of people drive drunk daily. And like mains voltages, pretty much everyone knows guns and drunk driving are and is dangerous. Really, how many people take apart their microwaves? Gotta be a tiny percentage I would think.


Trying to make "jack ass" videos for you tube?


Cripes Jeff, I make one Jack Ass video and you won't let me live that down. No more shares for you.

The only guilty part can be : mains transtormer, HV diode and HV capacitor.
A magnetron never dies.
A HV diode cannot be checked with standard tools.
The best is to check the HV at the cap (take care to your hands).
It must be some 10 kV or more.
For heating, refer to your control board.


Cursitor Doom a écrit le 22/03/2019 Ã* 20:37Â*:
Hi all,

I have had the same Daewoo microwave oven since I bought it new 7 years
ago and it's always performed *perfectly* up until today. This morning I
stuck some bread in it to defrost and it came out still frozen. No trace
of any heat at all. The platter rotates, the light comes on, the timer
counts down, the fan runs; all is working fine except for the total
absence of heat.
I'm given to understand that microwave ovens typically have a working
life of only around 2 years nowadays, so I'd really like to fix this one
up rather than replace it with something inevitably inferior. Any
suggestions as to what to check for? I have the gear to measure up to
50kV if necessary, and I'd guess the magnetron HT is considerably less
than that figure. So... where to start looking first?

In article , says...

Likely candidates are the HV diode & HV fuse. Of course it can be other
things. And of course they're in the killer section.

Spot on. Blown 5kV fuse and HV diode open circuit both directions.
Transformer secondary showing 188 ohms across the winding, so *hopefully*
a quick fix. But I'd better just check the magnetron first.......
:-/




What did you use to check the diode ? Many of the high voltage diodes
are actually several in series in the same package. Most meters will
not check them as there are several volts dropped across them.
The meters will often show them as open in both directions evenif they
are good.

A magnetron never dies.


say what?

the filament can open.

m

On Monday, March 25, 2019 at 12:34:31 PM UTC-4, Cursitor Doom wrote:
On Fri, 22 Mar 2019 14:18:03 -0700, tabbypurr wrote:

Likely candidates are the HV diode & HV fuse. Of course it can be other
things. And of course they're in the killer section.

Spot on. Blown 5kV fuse and HV diode open circuit both directions.
Transformer secondary showing 188 ohms across the winding, so *hopefully*
a quick fix. But I'd better just check the magnetron first.......
:-/





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Aside from sprinkling bits of technical troubleshooting and safety advice in a string of email exchanges, I was reminded of this comprehensive 'Microwave repair' document. Should be read and understood before one even unplugs the device to be repaired.

(When one considers that the charge stored in the microwave capacitor is significantly (x10+) the charge from public defibrillators (AEDs) the energy is definitely high enough to put a human being horizontal - permanently!)

https://www.repairfaq.org/sam/micfaq.htm#micpre

j

On 3/25/19 11:47 AM, John-Del wrote:
Cripes Jeff, I make one Jack Ass video and you won't let me live that down. No more shares for you.


Bwahahaha


--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com

On Mon, 25 Mar 2019 13:20:41 -0400, Ralph Mowery
wrote:

In article , says...

Likely candidates are the HV diode & HV fuse. Of course it can be other
things. And of course they're in the killer section.

Spot on. Blown 5kV fuse and HV diode open circuit both directions.
Transformer secondary showing 188 ohms across the winding, so *hopefully*
a quick fix. But I'd better just check the magnetron first.......
:-/

What did you use to check the diode ? Many of the high voltage diodes
are actually several in series in the same package. Most meters will
not check them as there are several volts dropped across them.
The meters will often show them as open in both directions evenif they
are good.

Yep. The normal "diode check" found on most meters doesn't work. I
usually get about 100Kohms in the forward direction and infinity in
the reverse on my Simpson 260 meter (which uses a 15v battery for the
high resistance scales):
https://www.partselect.com/Microwave+test-diode+repair.htm

Or, use a 9V battery
https://www.youtube.com/watch?v=1pp4LUrq4DM
https://www.youtube.com/watch?v=F1mTElvwcBg
https://www.youtube.com/watch?v=R7wpRRU8vEY

If the microwave oven doesn't kill you, perhaps the popcorn will?
"Man shocked to death by exploding microwave"
https://www.news24.com/World/News/man-shocked-to-death-by-exploding-microwave-20181109
Please remember that you have only one life to give to your hobby or
profession.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Mon, 25 Mar 2019 10:45:35 -0700, makolber wrote:

A magnetron never dies.


say what?

the filament can open.

There are two (safe) checks to test a magnetron: resistance between pins
both ways round should be less than 1ohm and resistance between each pin
and the 'tron case should be open-circuit.




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On Mon, 25 Mar 2019 13:20:41 -0400, Ralph Mowery wrote:

What did you use to check the diode ? Many of the high voltage diodes
are actually several in series in the same package. Most meters will
not check them as there are several volts dropped across them.
The meters will often show them as open in both directions evenif they
are good.

I used a 9v battery and just checked for low-res one way and high-res the
other. Totally dead in both directions.





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You cannot check a HV diode.
The only way for a microwave is to chek the HV at the cap, and the
filament some 10 A.

Cursitor Doom a écrit le 25/03/2019 Ã* 21:52Â*:
On Mon, 25 Mar 2019 13:20:41 -0400, Ralph Mowery wrote:

What did you use to check the diode ? Many of the high voltage diodes
are actually several in series in the same package. Most meters will
not check them as there are several volts dropped across them.
The meters will often show them as open in both directions evenif they
are good.
I used a 9v battery and just checked for low-res one way and high-res the
other. Totally dead in both directions.

On Mon, 25 Mar 2019 21:55:27 +0100, Look165 wrote:

You cannot check a HV diode.

I just have! Maybe it's YOU who has a problem with them?



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tabb the criminal moron troll wrote:



It would be sensible to say microwaves can electrocute people,


** Idiotic to say otherwise - you fool.

so we get abuse for agreeing with you lol


** We do not agree on anything.


not so sensible to insist everyone, despite not knowing what skills they do or don't have, does not have the necessary skills to work with them.

** Insane crap.

You must KNOW the person has the knowledge, skill and necessary safety gear on hand. Plus they must not work alone.

Neither I nor you need know what skill Mr Doom has.


** Irrelevant to you posting bad advice on a public forum which anyone can read at any time.


Impossible to ascertain that via usenet so the only safe option is to advise against and offer no help.

There are people taking that tack on any subject.


** Completely irrelevant garbage.

A false argument of the dumbest kind.



It's not difficult, just need to know the issues/gotchas.

** Totally insane crap.

One needs to be trained on the proper precautions with microwaves ovens and USE them.

If you understand the gotchas & are sensible you're going to use them. We can't do more than that on usenet.



** Dangerous drivel.

Erring on the side of caution is a foreign concept to a raving ****wit like you.


You are one dangerous ****ing idiot.


With respect you don't know what my working practices are with microwaves,


** Utter and COMPLETELY irrelevant, I was NOT talking about your or CD practices !!!!

The danger is of course to folk reading you ****ing tripe on this NG.


FYI:

You have a monstrous reading disability along with rampant autism and a bloated and diseased ego.

Plus you are a vile coward hiding behind a fake name and complete anonymity.

**** you.


..... Phil