First the dishwasher, now the microwave…

[Tim+]

After a mere 43 years of service our Toshiba ER-672ET has just stopped
heating stuff.

Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.

Of course it owes us nothing but we’re very fond of it. Is there any
prospect of a repair at this sort of age?

Tim

[Jack Harry Teesdale]

Post by Tim+
After a mere 43 years of service our Toshiba ER-672ET has just stopped
heating stuff.
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.
Of course it owes us nothing but we’re very fond of it. Is there any
prospect of a repair at this sort of age?
Tim

With new m/w ovens at the cheap prices they are today, repair is
unlikely economic even for d-i-y.

[Tim+]

Post by Jack Harry Teesdale

Post by Tim+
After a mere 43 years of service our Toshiba ER-672ET has just stopped
heating stuff.
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.
Of course it owes us nothing but we’re very fond of it. Is there any
prospect of a repair at this sort of age?
Tim

With new m/w ovens at the cheap prices they are today, repair is
unlikely economic even for d-i-y.

As I said, we’re very fond of it. It’s not always about the economics.

Tim

[Scott]

Post by Jack Harry Teesdale

Post by Tim+
After a mere 43 years of service our Toshiba ER-672ET has just stopped
heating stuff.
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.
Of course it owes us nothing but we’re very fond of it. Is there any
prospect of a repair at this sort of age?
Tim

With new m/w ovens at the cheap prices they are today, repair is
unlikely economic even for d-i-y.

As I said, we’re very fond of it. It’s not always about the economics.

Also, does the fact that it has lasted 43 years not indicate better
build quality than any replacement?

[Tim+]

Post by Scott

Post by Jack Harry Teesdale

Post by Tim+
After a mere 43 years of service our Toshiba ER-672ET has just stopped
heating stuff.
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.
Of course it owes us nothing but we’re very fond of it. Is there any
prospect of a repair at this sort of age?
Tim

With new m/w ovens at the cheap prices they are today, repair is
unlikely economic even for d-i-y.

As I said, we’re very fond of it. It’s not always about the economics.

Also, does the fact that it has lasted 43 years not indicate better
build quality than any replacement?

Well if “heft” is anything to go by, it’s got heaps of that! Weighs a
fecking ton! ;-)

Tim

[Andrew Gabriel]

Post by Tim+
Well if “heft” is anything to go by, it’s got heaps of that! Weighs a
fecking ton! ;-)

If you've ever fancied a spot-welder, that weighty transformer could be
repurposed.

[bilou]

Post by Tim+
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.

There is also a fan on the magnetron and a thermal switch.

[Tim+]

Post by bilou

Post by Tim+
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.

There is also a fan on the magnetron and a thermal switch.

Fan still works. My impression from the noises is that HV is being
generated, but that’s where everything stops.

Tim

[Theo]

Post by Tim+

Post by bilou

Post by Tim+
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.

There is also a fan on the magnetron and a thermal switch.

Fan still works. My impression from the noises is that HV is being
generated, but that’s where everything stops.

Anything can be repaired, included rusted planes from the bottom of the sea,
it's just a case of time and money. In this case it sounds like something
is wrong in the HT side of things, but whether it's the magnetron or
something else I couldn't say. How you would find somebody trained to have
a look, given the lethal voltages and currents involved, I don't know.
At the least they would need HV PPE (eg lineman gloves to the appropriate
voltage), since the capacitor may hold charge at HV.

Somebody here has taken apart a microwave of similar vintage:
https://www.ebay.co.uk/itm/223480060496

and it looks like there's a HV capacitor (~1uF at 2kV) and a diode. Maybe
those would be worth checking, assuming you can get at them safely.

Also to note you can buy a similar 'unused' one (the inside looks mint) for
barely more than a Tesco special:
https://www.ebay.co.uk/itm/195916497046

(although I don't know if radiation leakage on this vintage would be a
concern, supposedly early microwaves suffered from it. I suppose if it
hasn't killed you yet...)

Theo

[Tim+]

Post by Theo

Post by Tim+

Post by bilou

Post by Tim+
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.

There is also a fan on the magnetron and a thermal switch.

Fan still works. My impression from the noises is that HV is being
generated, but that’s where everything stops.

Anything can be repaired, included rusted planes from the bottom of the sea,
it's just a case of time and money. In this case it sounds like something
is wrong in the HT side of things, but whether it's the magnetron or
something else I couldn't say. How you would find somebody trained to have
a look, given the lethal voltages and currents involved, I don't know.
At the least they would need HV PPE (eg lineman gloves to the appropriate
voltage), since the capacitor may hold charge at HV.
https://www.ebay.co.uk/itm/223480060496
and it looks like there's a HV capacitor (~1uF at 2kV) and a diode. Maybe
those would be worth checking, assuming you can get at them safely.
Also to note you can buy a similar 'unused' one (the inside looks mint) for
https://www.ebay.co.uk/itm/195916497046

That’s a new fangled one with a digital timer. Definitely don’t want one of
them. The old electro-mechanical timer and olde worlde bell are two of the
best features of the old one. ;-)

Tim

[mm0fmf]

Post by Tim+
olde worlde bell

Popty-ping as our Welsh cousins would allegedly say.

[Theo]

Post by Tim+
That’s a new fangled one with a digital timer. Definitely don’t want one of
them. The old electro-mechanical timer and olde worlde bell are two of the
best features of the old one. ;-)

If you are so minded, the GTi model from the same range may be a source of
parts for the old one - you could do a complete transplant of the HV
section, assuming the parts are the same. It sounds like the digital front
panel is just mains-side - ie the timer just switches the mains to the HV
transformer, and it doesn't make a difference whether that timer is digital
or analogue, the HV circuit is maybe the same?

Although whether it's worth doing that, given the HV and RF risks, is
another question.

Theo

[The Natural Philosopher]

Post by Theo

Post by Tim+
That’s a new fangled one with a digital timer. Definitely don’t want one of
them. The old electro-mechanical timer and olde worlde bell are two of the
best features of the old one. ;-)

If you are so minded, the GTi model from the same range may be a source of
parts for the old one - you could do a complete transplant of the HV
section, assuming the parts are the same. It sounds like the digital front
panel is just mains-side - ie the timer just switches the mains to the HV
transformer, and it doesn't make a difference whether that timer is digital
or analogue, the HV circuit is maybe the same?
Although whether it's worth doing that, given the HV and RF risks, is
another question.
Theo

I spent a bit more for a semi pro one. Power setting, timer knob and a
ping. Stainless steel easy clean

https://www.thecateringwarehouse.uk/buffalo-manual-commercial-microwave-oven-1100w-gk643-56467-p.asp

Like Tim+ I don't need all that digital shit.
I just wanted a solid microwave.

[Theo]

Post by The Natural Philosopher
I spent a bit more for a semi pro one. Power setting, timer knob and a
ping. Stainless steel easy clean
https://www.thecateringwarehouse.uk/buffalo-manual-commercial-microwave-oven-1100w-gk643-56467-p.asp
Like Tim+ I don't need all that digital shit.
I just wanted a solid microwave.

That's not a bad plan. You also get more power than a domestic one, so it
cooks quicker (one thing I noticed when moving from a 700W to a 900W).

It seems like once you go beyond £30 Asda clockwork specials, you get a
fancier control panel with a ton of features that nobody uses. At least the
pro manufacturers know they will never use them and don't bother.

(it seems like Buffalo = Samsung here)

Theo

[Robin]

Post by Theo

Post by The Natural Philosopher
I spent a bit more for a semi pro one. Power setting, timer knob and a
ping. Stainless steel easy clean
https://www.thecateringwarehouse.uk/buffalo-manual-commercial-microwave-oven-1100w-gk643-56467-p.asp
Like Tim+ I don't need all that digital shit.
I just wanted a solid microwave.

That's not a bad plan. You also get more power than a domestic one, so it
cooks quicker (one thing I noticed when moving from a 700W to a 900W).
It seems like once you go beyond £30 Asda clockwork specials, you get a
fancier control panel with a ton of features that nobody uses. At least the
pro manufacturers know they will never use them and don't bother.
Both microwaves I've had since the 1980s came with digital programmers.

I still make of the use their facilities frequently to set a delayed
start on the microwave and a programme of different cooking times and
different power levels. E.g. I can put veg in the microwave, main in a
conventional oven, and come back when both are ready. Naturally no
commercial kitchen will cook like that but I don't see why I should be
chained in the kitchen like a galley slave :)

[Rod Speed]

I spent a bit more for a semi pro one. Power setting, timer knob and=

a

ping. Stainless steel easy clean
https://www.thecateringwarehouse.uk/buffalo-manual-commercial-microw=

ave-oven-1100w-gk643-56467-p.asp

Like Tim+ I don't need all that digital shit.
I just wanted a solid microwave.

That's not a bad plan. You also get more power than a domestic one,=

=

so it
cooks quicker (one thing I noticed when moving from a 700W to a 900W)=

.

It seems like once you go beyond =A330 Asda clockwork specials, you =

get a

fancier control panel with a ton of features that nobody uses. At =
least the
pro manufacturers know they will never use them and don't bother.
Both microwaves I've had since the 1980s came with digital programmer=

s.

I still make of the use their facilities frequently to set a delayed =
start on the microwave and a programme of different cooking times and =

=

different power levels. E.g. I can put veg in the microwave, main in =

a =

conventional oven, and come back when both are ready.

And rice cooked by absorption works much better when you
can have two different stages, first on full power to get the
water boiling and then the second phase on med-low power.

Naturally no commercial kitchen will cook like that but I don't see wh=

y =

I should be chained in the kitchen like a galley slave :)

And I would prefer both appliances to be app controlled
so you can have a set of canned meal recipies with your
own name and picture and just tap that to do all that
needs to be done for a particular meal and just tell you
when its all ready to plate and eat. Appliances should
be my slaves.

[Peeler]

On Fri, 04 Aug 2023 09:37:33 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

<FLUSH the abnormal trolling senile cretin's latest trollshit unread>

[SteveW]

Post by Robin

Post by The Natural Philosopher
I spent a bit more for a semi pro one. Power setting, timer knob and a
ping. Stainless steel easy clean
https://www.thecateringwarehouse.uk/buffalo-manual-commercial-microwave-oven-1100w-gk643-56467-p.asp
Like Tim+ I don't need all that digital shit.
I just wanted a solid microwave.

That's not a bad plan.  You also get more power than a domestic one,
so it
cooks quicker (one thing I noticed when moving from a 700W to a 900W).
It seems like once you go beyond £30 Asda clockwork specials, you get a
fancier control panel with a ton of features that nobody uses.  At
least the
pro manufacturers know they will never use them and don't bother.
Both microwaves I've had since the 1980s came with digital programmers.

I still make of the use their facilities frequently to set a delayed
start on the microwave and a programme of different cooking times and
different power levels.  E.g. I can put veg in the microwave, main in a
conventional oven, and come back when both are ready.  Naturally no
commercial kitchen will cook like that but I don't see why I should be
chained in the kitchen like a galley slave :)

Digital timers are also good for precision. For instance, I occasionally
buy some dough-balls with a garlic butter dip. I know that exactly 12
seconds will leave the dip just right. 11 seconds or 13 seconds and it
is slightly too solid or slightly too liquid.

[Robin]

Post by SteveW

Post by Robin

Post by The Natural Philosopher
I spent a bit more for a semi pro one. Power setting, timer knob and a
ping. Stainless steel easy clean
https://www.thecateringwarehouse.uk/buffalo-manual-commercial-microwave-oven-1100w-gk643-56467-p.asp
Like Tim+ I don't need all that digital shit.
I just wanted a solid microwave.

That's not a bad plan.  You also get more power than a domestic one,
so it
cooks quicker (one thing I noticed when moving from a 700W to a 900W).
It seems like once you go beyond £30 Asda clockwork specials, you get a
fancier control panel with a ton of features that nobody uses.  At
least the
pro manufacturers know they will never use them and don't bother.
Both microwaves I've had since the 1980s came with digital programmers.

I still make of the use their facilities frequently to set a delayed
start on the microwave and a programme of different cooking times and
different power levels.  E.g. I can put veg in the microwave, main in
a conventional oven, and come back when both are ready.  Naturally no
commercial kitchen will cook like that but I don't see why I should be
chained in the kitchen like a galley slave :)

Digital timers are also good for precision. For instance, I occasionally
buy some dough-balls with a garlic butter dip. I know that exactly 12
seconds will leave the dip just right. 11 seconds or 13 seconds and it
is slightly too solid or slightly too liquid.

Spot on. My 1980s oven allowed that. Sadly the Panasonic that replaced
it only allows 10 second chunks. I've had to adapt by setting e.g. 10
seconds at 1000W then 10 seconds at 250W. As with most things though,
needs a lot more button presses :(

[Cw]

We've got exactly the same model, it's practically a family heirloom. Belonged to my wife's late grandmother.
It stopped working in the late 1990s and we had it repaired straight away, repair cost about £40. Same symptoms as yours, I think that it needed a new magnetron.
It's been working fine ever since although in 2007 we upgraded to a combi with grill and convection.
We're now on our third combi microwave, each combi has stopped working due to a failed magnetron. Cheap combis weren't worth fixing when second hand replacements were available for less than the price of a new magnetron - and what's the point in repairing something that didn't last long in the first place? It'll just break again.
The Toshiba ER 672-ET is a different matter, it's clearly well engineered and built to last. Back in the late 1990s the repairer said it probably wasn't economic to repair! We've lent it to friends and relatives since we bought the combi in 2007, it always comes back to us when they move house/fit a new kitchen etc.
It's led a hard life, been moved multiple times, something that is often the death knell of consumer appliances.
Our most recent combi broke the other day so we're back with the Toshiba ER 672-ET. We'll get another combi because they're great for doing pizzas and baked potatoes but we're hanging on to the Toshiba and we'll pay to get it fixed if it ever goes wrong again.
That £40 repair that the repairer said wasn't worthwhile has turned out to be an absolute bargain.
So in conclusion, yes, it is worth it.
Parts are available second have on ebay and amazon etc

[Nick Odell]

On Sat, 02 Dec 2023 17:33:05 +0000, Cw

Post by Cw
We've got exactly the same model, it's practically a family heirloom. Belonged to my wife's late grandmother.
It stopped working in the late 1990s and we had it repaired straight away, repair cost about £40. Same symptoms as yours, I think that it needed a new magnetron.
It's been working fine ever since although in 2007 we upgraded to a combi with grill and convection.
We're now on our third combi microwave, each combi has stopped working due to a failed magnetron. Cheap combis weren't worth fixing when second hand replacements were available for less than the price of a new magnetron - and what's the point in repairing something that didn't last long in the first place? It'll just break again.
The Toshiba ER 672-ET is a different matter, it's clearly well engineered and built to last. Back in the late 1990s the repairer said it probably wasn't economic to repair! We've lent it to friends and relatives since we bought the combi in 2007, it always comes back to us when they move house/fit a new kitchen etc.
It's led a hard life, been moved multiple times, something that is often the death knell of consumer appliances.
Our most recent combi broke the other day so we're back with the Toshiba ER 672-ET. We'll get another combi because they're great for doing pizzas and baked potatoes but we're hanging on to the Toshiba and we'll pay to get it fixed if it ever goes wrong again.
That £40 repair that the repairer said wasn't worthwhile has turned out to be an absolute bargain.
So in conclusion, yes, it is worth it.
Parts are available second have on ebay and amazon etc.

(reply tagged on here because I can't see the full thread on Eternal
September)

I'd certainly endorse looking at getting it fixed. If as has been
suggested it's the magnetron heater then it could be a no-go but there
are other possibilities IMO. There are several big fuses on the main
board of my Sanyo and one of them died so much of the rest of the
machine kept on working. Why did it die? Well, it was forty years old
and had just grown tired of life, I guess. It's replacement has
soldiered on without any problem. There's a degree of vibration in the
system so I wouldn't dismiss a possible fatigue fracture of a joint or
a wire somewhere. That somewhere is IMO in a low tension circuit
otherwise an HT fracture would almost certainly be arcing and you'd
know about it.

It's worth having a poke around - but as others have said, for
goodness sake make sure everything is completely discharged first!

Nick

[Flashg]

Tim.

I have one of these with a broken handle. My mother in law is looking to scrap it! Everything else works fine.

Get if you want it for free. Based near Wigan. Would be cool to see it used forever. She got it as a wedding gift in 1983!

If you reply on here I think I can pass you my email somehow.

[Tim+]

Post by Flashg
Tim.
I have one of these with a broken handle. My mother in law is looking to
scrap it! Everything else works fine.
Get if you want it for free. Based near Wigan. Would be cool to see it
used forever. She got it as a wedding gift in 1983!
If you reply on here I think I can pass you my email somehow.

No need but thanks. Having dragged it out for a repair man to have a look
at it, it spontaneously healed itself and is soldiering on magnificently.

Incidentally, I found that searching for a magnetron based on the model
number printed on it, I found a compatible replacement so when the
magnetron *does* die, I should be able to replace it.

Tim

[Michael Chare]

Post by Tim+

Post by Theo

Post by Tim+

Post by bilou

Post by Tim+
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.

There is also a fan on the magnetron and a thermal switch.

Fan still works. My impression from the noises is that HV is being
generated, but that’s where everything stops.

Anything can be repaired, included rusted planes from the bottom of the sea,
it's just a case of time and money. In this case it sounds like something
is wrong in the HT side of things, but whether it's the magnetron or
something else I couldn't say. How you would find somebody trained to have
a look, given the lethal voltages and currents involved, I don't know.
At the least they would need HV PPE (eg lineman gloves to the appropriate
voltage), since the capacitor may hold charge at HV.
https://www.ebay.co.uk/itm/223480060496
and it looks like there's a HV capacitor (~1uF at 2kV) and a diode. Maybe
those would be worth checking, assuming you can get at them safely.
Also to note you can buy a similar 'unused' one (the inside looks mint) for
https://www.ebay.co.uk/itm/195916497046

That’s a new fangled one with a digital timer. Definitely don’t want one of
them. The old electro-mechanical timer and olde worlde bell are two of the
best features of the old one. ;-)
Tim

The small £50 microwave I bought from Argos a few days ago has both of
those. Has settings on the power level and time rotating knobs for
defrosting.

[The Natural Philosopher]

Post by Michael Chare

Post by Tim+

Post by Theo

Post by bilou

Post by Tim+
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.

There is also a fan on the magnetron and a thermal switch.

Fan still works.  My impression from the noises is that HV is being
generated, but that’s where everything stops.

Anything can be repaired, included rusted planes from the bottom of the sea,
it's just a case of time and money.  In this case it sounds like
something
is wrong in the HT side of things, but whether it's the magnetron or
something else I couldn't say.  How you would find somebody trained
to have
a look, given the lethal voltages and currents involved, I don't know.
At the least they would need HV PPE (eg lineman gloves to the appropriate
voltage), since the capacitor may hold charge at HV.
https://www.ebay.co.uk/itm/223480060496
and it looks like there's a HV capacitor (~1uF at 2kV) and a diode.
Maybe
those would be worth checking, assuming you can get at them safely.
Also to note you can buy a similar 'unused' one (the inside looks mint) for
https://www.ebay.co.uk/itm/195916497046

That’s a new fangled one with a digital timer. Definitely don’t want one of
them.  The old electro-mechanical timer and olde worlde bell are two
of the
best features of the old one. ;-)
Tim

The small £50 microwave I bought from Argos a few days ago has both of
those.  Has settings on the power level and time rotating knobs for
defrosting.

I got similar in tesco, but it was small

[Brian Gaff]

I have a talking microwave that needs repairing, but its only half the age
of that one and spares are no longer made, so if its an ordinary part, then
these may be repairable, but though its a shame, it does seem that if its a
part made only for that model, you are stuffed. In the case of mine I think
its the low voltage psu inside, but your fault could be part of the ladder
of rectifiers used to power the Magnetron, then you need to decide what blew
them, if it was just a mains spike, then it might be worth fixing. You could
be lucky and find its the relay of course.
I think it would be a labour of love though unless price is no object, most
things can be fixed up to work, I've never seen a Magnetron fault, they
generally just get less efficient with age.
Brian
--
--:
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...
***@blueyonder.co.uk
Blind user, so no pictures please
Note this Signature is meaningless.!

Post by Tim+
After a mere 43 years of service our Toshiba ER-672ET has just stopped
heating stuff.
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there's just a faint cracking
noise.
Of course it owes us nothing but we're very fond of it. Is there any
prospect of a repair at this sort of age?
Tim

With new m/w ovens at the cheap prices they are today, repair is unlikely
economic even for d-i-y.

[SteveW]

Post by Tim+
After a mere 43 years of service our Toshiba ER-672ET has just stopped
heating stuff.
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.
Of course it owes us nothing but we’re very fond of it. Is there any
prospect of a repair at this sort of age?

I'd check than an internal fuse hasn't failed - age can eventually get
to them without a fault.

Other than than, I don't think I'd bother with a repair at that age.

[Tim+]

Post by SteveW

Post by Tim+
After a mere 43 years of service our Toshiba ER-672ET has just stopped
heating stuff.
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.
Of course it owes us nothing but we’re very fond of it. Is there any
prospect of a repair at this sort of age?

I'd check than an internal fuse hasn't failed - age can eventually get
to them without a fault.

If a fuse had gone would the light come on, the turntable turn and the
magnetron make hissy crackly noises?

Post by SteveW
Other than than, I don't think I'd bother with a repair at that age.

See my other replies on that subject.

Tim

[SteveW]

Post by Tim+

Post by SteveW

Post by Tim+
After a mere 43 years of service our Toshiba ER-672ET has just stopped
heating stuff.
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.
Of course it owes us nothing but we’re very fond of it. Is there any
prospect of a repair at this sort of age?

I'd check than an internal fuse hasn't failed - age can eventually get
to them without a fault.

If a fuse had gone would the light come on, the turntable turn and the
magnetron make hissy crackly noises?

I don't know the circuit of your microwave, but it is not uncommon for
just a specific part of the circuit to be separately fused.

[Chris Hogg]

Post by SteveW

Post by Tim+

Post by SteveW

Post by Tim+
After a mere 43 years of service our Toshiba ER-672ET has just stopped
heating stuff.
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.
Of course it owes us nothing but we’re very fond of it. Is there any
prospect of a repair at this sort of age?

I'd check than an internal fuse hasn't failed - age can eventually get
to them without a fault.

If a fuse had gone would the light come on, the turntable turn and the
magnetron make hissy crackly noises?

I don't know the circuit of your microwave, but it is not uncommon for
just a specific part of the circuit to be separately fused.

Don't forget, there are some dangerously high voltages kicking around
in a microwave, even after it's turned off, so I'm told.

[Tim+]

Post by Chris Hogg

Post by SteveW

Post by Tim+

Post by SteveW

Post by Tim+
After a mere 43 years of service our Toshiba ER-672ET has just stopped
heating stuff.
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.
Of course it owes us nothing but we’re very fond of it. Is there any
prospect of a repair at this sort of age?

I'd check than an internal fuse hasn't failed - age can eventually get
to them without a fault.

If a fuse had gone would the light come on, the turntable turn and the
magnetron make hissy crackly noises?

I don't know the circuit of your microwave, but it is not uncommon for
just a specific part of the circuit to be separately fused.

Don't forget, there are some dangerously high voltages kicking around
in a microwave, even after it's turned off, so I'm told.

I’m not going to DIY this one, just after opinions as to whether repairs
are *possible* on a machine of this age.

Tim

[Rod Speed]

After a mere 43 years of service our Toshiba ER-672ET has just =
stopped
heating stuff.
Lights on, countdown timer working, turntable rotating but instea=

d =

of the
normal hum when the magnetron is energised there=C2=92s just a fa=

int =

cracking
noise.
Of course it owes us nothing but we=C2=92re very fond of it. Is =

there =

any
prospect of a repair at this sort of age?

I'd check than an internal fuse hasn't failed - age can eventually=

=

get
to them without a fault.

If a fuse had gone would the light come on, the turntable turn and =

the

magnetron make hissy crackly noises?

I don't know the circuit of your microwave, but it is not uncommon f=

or

just a specific part of the circuit to be separately fused.

Don't forget, there are some dangerously high voltages kicking around=
in a microwave, even after it's turned off, so I'm told.

I=E2=80=99m not going to DIY this one, just after opinions as to wheth=

er repairs

are *possible* on a machine of this age.

Not possible to say unless its known what has failed
and the availability of what has failed is known

[Peeler]

On Thu, 03 Aug 2023 08:52:10 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

<FLUSH the abnormal trolling senile cretin's latest trollshit unread>

[Paul]

Post by Tim+

Post by SteveW

Post by Tim+
After a mere 43 years of service our Toshiba ER-672ET has just stopped
heating stuff.
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.
Of course it owes us nothing but we’re very fond of it. Is there any
prospect of a repair at this sort of age?

I'd check than an internal fuse hasn't failed - age can eventually get
to them without a fault.

If a fuse had gone would the light come on, the turntable turn and the
magnetron make hissy crackly noises?

Post by SteveW
Other than than, I don't think I'd bother with a repair at that age.

See my other replies on that subject.
Tim

The primary has a slo blow fuse on it. Likely soldered in place.

Those do not normally fail for nothing.

Your fuse is still operational. The crackling tells you that,
that HV is present on the oil-filled capacitor. But the magnetron
has gone open circuit.

Appliance parts are not stocked for forty years. That's a bit too long.

*******

Here is a schematic.

https://www.researchgate.net/figure/Schematic-diagram-of-the-magnetron-operation-circuit-in-a-microwave-oven-The-switch_fig1_234930316

Notice there is a relay. C1 is the oil-filled capacitor.
D1 is the high voltage diode.

The magnetron has a filament. If the filament opens, no juice
can flow. If the metallic surfaces in the circuit path are
eroded away, no juice flows.

And if C1 arcs over, it is loud enough to knock out hearing
in one ear for ten minutes (you've been warned). Arcing does not
damage anything, if it happens, except your hearing. If you cook a lot
of microwave popcorn, in legacy (like yours) microwave ovens,
that's when an arc-over occurs. Butter&salt conduct. Normal home
cooking mixes it up enough, that's less likely to happen. The
machine at work, was getting one bag of microwave popcorn after
another, so I suppose the result is inevitable for it. (I wasn't
actually making microwave popcorn at the time. Huh.) Some of the
newer microwaves have a conformal coating to protect some of it from
HV discharge.

Newer microwaves have an inverter (SMPS). One of the "benefits",
is power modulation from at least 70% to 100%. If you ask the microwave to
run at 70%, it just drops the output voltage enough to do that. If
you ask for too low of a voltage, it goes back to modulating the
machine via the relay. (On for 20, off for 10. Etc)

Paul

[Tim+]

Post by Paul

Post by Tim+

Post by SteveW

Post by Tim+
After a mere 43 years of service our Toshiba ER-672ET has just stopped
heating stuff.
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.
Of course it owes us nothing but we’re very fond of it. Is there any
prospect of a repair at this sort of age?

I'd check than an internal fuse hasn't failed - age can eventually get
to them without a fault.

If a fuse had gone would the light come on, the turntable turn and the
magnetron make hissy crackly noises?

Post by SteveW
Other than than, I don't think I'd bother with a repair at that age.

See my other replies on that subject.
Tim

The primary has a slo blow fuse on it. Likely soldered in place.
Those do not normally fail for nothing.
Your fuse is still operational. The crackling tells you that,
that HV is present on the oil-filled capacitor.

That’s certainly my thinking.

Post by Paul
But the magnetron
has gone open circuit.

Bugger.

Post by Paul
Appliance parts are not stocked for forty years. That's a bit too long.

Well I kinda know that but I was wondering whether a component like the
magnetron might have been used unaltered for enough years to be available.
I’ll have a peek under the cover an look for a part number. I do accept
that it’s unlikely to be available.

Post by Paul
*******
Here is a schematic.
https://www.researchgate.net/figure/Schematic-diagram-of-the-magnetron-operation-circuit-in-a-microwave-oven-The-switch_fig1_234930316

My machine has the full circuit diagram stuck to the inside of the cover.

Thanks for your feedback Paul, I was kinda hoping that I’d get at least one
sensible reply. ;-)

Tim

[Rod Speed]

After a mere 43 years of service our Toshiba ER-672ET has just stoppe=

d

heating stuff.
Lights on, countdown timer working, turntable rotating but instead o=

f =

the
normal hum when the magnetron is energised there=E2=80=99s just a fai=

nt cracking

noise.
Of course it owes us nothing but we=E2=80=99re very fond of it. Is =

there any

prospect of a repair at this sort of age?

I'd check than an internal fuse hasn't failed - age can eventually get=

=

to them without a fault.

Unlikely to be faint crackling if that is the problem.

Other than than, I don't think I'd bother with a repair at that age.

[Peeler]

On Thu, 03 Aug 2023 08:41:10 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

<FLUSH the abnormal trolling senile cretin's latest trollshit unread>

[Fredxx]

Post by Tim+
After a mere 43 years of service our Toshiba ER-672ET has just stopped
heating stuff.
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.

My first thought is the magnetron heater has gone o/c. And the resultant
increase in HT is causing the crackling but could be another failing
component.

The internals of microwaves can be the most dangerous of all household
devices due to the lethal voltage and power associated with that voltage.

Magnetrons are incredibly simple. With a transformer, diode, capacitor
and a magnetron. Repair is easy but extreme precautions must be taken.

There are some good YouTube videos on the subject.

[Clive Arthur]

Post by Tim+
After a mere 43 years of service our Toshiba ER-672ET has just stopped
heating stuff.
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.
Of course it owes us nothing but we’re very fond of it. Is there any
prospect of a repair at this sort of age?
Tim

It's possible a build-up of dusty gunge has made a new path for the HV,
so give it a good clean inside with IPA.

[Fredxx]

Post by Clive Arthur

Post by Tim+
After a mere 43 years of service our Toshiba ER-672ET has just stopped
heating stuff.
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.
Of course it owes us nothing but we’re very fond of it.  Is there any
prospect of a repair at this sort of age?
Tim

It's possible a build-up of dusty gunge has made a new path for the HV,
so give it a good clean inside with IPA.

That doesn't normally result in a non-working microwave.

There is so much power involved that an arc would normally blow away any
"gunge" and if anything became conductive on a larger scale then this
would result in lots of magic smoke.

[John Rumm]

Post by Tim+
After a mere 43 years of service our Toshiba ER-672ET has just stopped
heating stuff.
Lights on, countdown timer working, turntable rotating but instead of the
normal hum when the magnetron is energised there’s just a faint cracking
noise.
Of course it owes us nothing but we’re very fond of it. Is there any
prospect of a repair at this sort of age?

The cracking sound suggests that the HT is still working, so chances are
the filament on the magnetron has failed. The things usually have an
quoted life of 2000 hours - but that is at the point where they have
lost 20% or more output, not complete failure. So it is not uncommon for
them to run for significantly longer times but with falling output power.

We replaced our original MW last year - it was 30 years old and still
worked - but cooking times were getting noticeably longer.
--
Cheers,

John.

/=================================================================\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\=================================================================/

[Rod Speed]

On Thu, 03 Aug 2023 20:59:52 +1000, John Rumm =

After a mere 43 years of service our Toshiba ER-672ET has just stoppe=

d

heating stuff.
Lights on, countdown timer working, turntable rotating but instead o=

f =

the
normal hum when the magnetron is energised there=E2=80=99s just a fai=

nt cracking

noise.
Of course it owes us nothing but we=E2=80=99re very fond of it. Is =

there any

prospect of a repair at this sort of age?

The cracking sound suggests that the HT is still working, so chances a=

re =

the filament on the magnetron has failed. The things usually have an =
quoted life of 2000 hours - but that is at the point where they have =
lost 20% or more output, not complete failure. So it is not uncommon f=

or =

them to run for significantly longer times but with falling output pow=

er.

We replaced our original MW last year - it was 30 years old and still =

=

worked - but cooking times were getting noticeably longer.

My National is now quite literally 50 years old and is still going fine
and doesnt take any longer than it used to and has been used
virtually every single day in that time. I don't use it to boil a mug
of water for tea or coffee tho, most days just to cook the frozen peas
and beans and corn and before I got the digital air fryers, a single
potato in its jacket.

[Peeler]

On Fri, 04 Aug 2023 04:48:01 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

<FLUSH the abnormal trolling senile cretin's latest trollshit unread>