R
Robert
Guest
I turned an empty microwave on for about 30 seconds. What is the potential
damage I have caused?
damage I have caused?
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J
Jasen Betts
Guest
On 2016-01-26, Robert <robert@no.email> wrote:
you've wasted several micro-cents worth or electricity.
AIUI the first thing to overheat is the glass platter.
--
\_(ă)_
I turned an empty microwave on for about 30 seconds. What is the potential
damage I have caused?
you've wasted several micro-cents worth or electricity.
AIUI the first thing to overheat is the glass platter.
--
\_(ă)_
P
Phil Allison
Guest
Robert wrote:
** Potentially, it can cause arcing in the wave guide leading to the oven enclosure. Then a fuse blows.
However, most microwave ovens are immune from the effect, but makers still advise never to do it.
I happen to own one that isn't immune, a Samsung MB245.
I cannot use it to thaw a frozen bottle of lemonade, or it arcs up.
.... Phil
I turned an empty microwave on for about 30 seconds.
What is the potential damage I have caused?
** Potentially, it can cause arcing in the wave guide leading to the oven enclosure. Then a fuse blows.
However, most microwave ovens are immune from the effect, but makers still advise never to do it.
I happen to own one that isn't immune, a Samsung MB245.
I cannot use it to thaw a frozen bottle of lemonade, or it arcs up.
.... Phil
C
Clocky
Guest
On 26/01/2016 12:51 PM, Robert wrote:
Extremely unlikely to have caused any damage.
I turned an empty microwave on for about 30 seconds. What is the
potential damage I have caused?
Extremely unlikely to have caused any damage.
I
Ian Field
Guest
"Phil Allison" <pallison49@gmail.com> wrote in message
news:c17ef3d9-20ec-4e4e-a4ba-0a0b2a4e7857@googlegroups.com...
Its highly likely that any food spatter on the dielectric window that covers
the end of the waveguide will carbonise and evolve a lot of heat and start
arcing.
I've never bought a microwave new - I won plenty with arcing dielectric
window - I just remove that and throw it away.
If you do that; don't do the exploding egg trick - a chunk of egg landed in
the waveguide and the overload killed the mains transformer.
news:c17ef3d9-20ec-4e4e-a4ba-0a0b2a4e7857@googlegroups.com...
Robert wrote:
I turned an empty microwave on for about 30 seconds.
What is the potential damage I have caused?
** Potentially, it can cause arcing in the wave guide leading to the oven
enclosure. Then a fuse blows.
Its highly likely that any food spatter on the dielectric window that covers
the end of the waveguide will carbonise and evolve a lot of heat and start
arcing.
I've never bought a microwave new - I won plenty with arcing dielectric
window - I just remove that and throw it away.
If you do that; don't do the exploding egg trick - a chunk of egg landed in
the waveguide and the overload killed the mains transformer.
W
Wayne Chirnside
Guest
On Tue, 26 Jan 2016 17:45:35 +0000, Ian Field wrote:
WWW.aliexpress.com
..97 cents for 1 or 2.57 for 5 mica cut to size replacement waveguide
window material.
It ain't mica, some kind of composite that works just as well.
snagged a 900 watt unit last week tossed.
Replace window - free microwave.
Ebay also sell the stuff.
"Phil Allison" <pallison49@gmail.com> wrote in message
news:c17ef3d9-20ec-4e4e-a4ba-0a0b2a4e7857@googlegroups.com...
Robert wrote:
I turned an empty microwave on for about 30 seconds.
What is the potential damage I have caused?
** Potentially, it can cause arcing in the wave guide leading to the
oven enclosure. Then a fuse blows.
Its highly likely that any food spatter on the dielectric window that
covers the end of the waveguide will carbonise and evolve a lot of heat
and start arcing.
I've never bought a microwave new - I won plenty with arcing dielectric
window - I just remove that and throw it away.
If you do that; don't do the exploding egg trick - a chunk of egg landed
in the waveguide and the overload killed the mains transformer.
WWW.aliexpress.com
..97 cents for 1 or 2.57 for 5 mica cut to size replacement waveguide
window material.
It ain't mica, some kind of composite that works just as well.
snagged a 900 watt unit last week tossed.
Replace window - free microwave.
Ebay also sell the stuff.
I
Ian Field
Guest
"Wayne Chirnside" <mark@faux.com> wrote in message
news:ZzOpy.272509$zT1.68906@fx26.iad...
Its not free if you have to buy a dielectric window.
The last one got retired because the bottom rusted through where a wonky
dish scraped through the paint, it was still going strong - which made it a
leakage hazard.
I'm willing the current microwave to turn its toes up because there's a
rather nice LG grill combo waiting to take its place.
news:ZzOpy.272509$zT1.68906@fx26.iad...
On Tue, 26 Jan 2016 17:45:35 +0000, Ian Field wrote:
"Phil Allison" <pallison49@gmail.com> wrote in message
news:c17ef3d9-20ec-4e4e-a4ba-0a0b2a4e7857@googlegroups.com...
Robert wrote:
I turned an empty microwave on for about 30 seconds.
What is the potential damage I have caused?
** Potentially, it can cause arcing in the wave guide leading to the
oven enclosure. Then a fuse blows.
Its highly likely that any food spatter on the dielectric window that
covers the end of the waveguide will carbonise and evolve a lot of heat
and start arcing.
I've never bought a microwave new - I won plenty with arcing dielectric
window - I just remove that and throw it away.
If you do that; don't do the exploding egg trick - a chunk of egg landed
in the waveguide and the overload killed the mains transformer.
WWW.aliexpress.com
.97 cents for 1 or 2.57 for 5 mica cut to size replacement waveguide
window material.
It ain't mica, some kind of composite that works just as well.
snagged a 900 watt unit last week tossed.
Replace window - free microwave.
Ebay also sell the stuff.
Its not free if you have to buy a dielectric window.
The last one got retired because the bottom rusted through where a wonky
dish scraped through the paint, it was still going strong - which made it a
leakage hazard.
I'm willing the current microwave to turn its toes up because there's a
rather nice LG grill combo waiting to take its place.
T
Trevor Wilson
Guest
On 26/01/2016 3:51 PM, Robert wrote:
**Magnetrons take around 2 seconds to reach maximum output. So, you have
operated the magnetron for 28 seconds with no load. As others have
stated, you have probably not caused fatal damage to the magnetron
(around 1 minute or more will almost certainly cause that), but you have
probably decreased the operating life of the magnetron by some amount.
Damage varies, but emission will likely be affected somewhat (probably
not noticeable). You can test the performance of the magnetron with a
measured quantity of water, an accurate thermometer and timer. Here's
how (you'll need a digital thermometer with reasonable resolution):
* Fill two containers with precisely 1 Litre of water each at roughly 20
degrees C. Measure the temperature of the water accurately.
* Place both containers side by side, near the centre of the oven.
* Set the MO 2 minutes + 2 seconds (magnetron warm-up time).
* Take both containers out, stir the water and measure and record the
temperatures.
* Calculate the temperature difference (before and after heating).
Record the figures.
* The actual power output of the MO is given by the equation: 70 X delta
temp. Compare the measured MO power with the manufacturer's claimed
output power (which is NOT the INPUT power to the MO). It should be
+/-15%.
--
Trevor Wilson
www.rageaudio.com.au
---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
I turned an empty microwave on for about 30 seconds. What is the
potential damage I have caused?
**Magnetrons take around 2 seconds to reach maximum output. So, you have
operated the magnetron for 28 seconds with no load. As others have
stated, you have probably not caused fatal damage to the magnetron
(around 1 minute or more will almost certainly cause that), but you have
probably decreased the operating life of the magnetron by some amount.
Damage varies, but emission will likely be affected somewhat (probably
not noticeable). You can test the performance of the magnetron with a
measured quantity of water, an accurate thermometer and timer. Here's
how (you'll need a digital thermometer with reasonable resolution):
* Fill two containers with precisely 1 Litre of water each at roughly 20
degrees C. Measure the temperature of the water accurately.
* Place both containers side by side, near the centre of the oven.
* Set the MO 2 minutes + 2 seconds (magnetron warm-up time).
* Take both containers out, stir the water and measure and record the
temperatures.
* Calculate the temperature difference (before and after heating).
Record the figures.
* The actual power output of the MO is given by the equation: 70 X delta
temp. Compare the measured MO power with the manufacturer's claimed
output power (which is NOT the INPUT power to the MO). It should be
+/-15%.
--
Trevor Wilson
www.rageaudio.com.au
---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
P
Phil Allison
Guest
Robert wrote:
** A few seconds after the oven is switched on, a visible and audible arc starts up at the top of the wave guide - just behind the mica window. It quickly burns the paint in that area and the oven must be switched off immediately.
The oven originally belonged to a local café and the owners dumped the thing on my doorstep when Samsung refused to replace it under warranty.
Powering up a microwave with nothing inside is an everyday event in busy cafes.
..... Phil
"Phil Allison"
** Potentially, it can cause arcing in the wave guide leading to the oven
enclosure. Then a fuse blows.
However, most microwave ovens are immune from the effect, but makers still
advise never to do it.
I happen to own one that isn't immune, a Samsung MB245.
I cannot use it to thaw a frozen bottle of lemonade, or it arcs up.
Mine is a new Samsung ME73M.
What do you mean by 'arc up' ?
** A few seconds after the oven is switched on, a visible and audible arc starts up at the top of the wave guide - just behind the mica window. It quickly burns the paint in that area and the oven must be switched off immediately.
The oven originally belonged to a local café and the owners dumped the thing on my doorstep when Samsung refused to replace it under warranty.
Powering up a microwave with nothing inside is an everyday event in busy cafes.
..... Phil
R
Robert
Guest
"Phil Allison" <pallison49@gmail.com> wrote in message
news:c17ef3d9-20ec-4e4e-a4ba-0a0b2a4e7857@googlegroups.com...
Mine is a new Samsung ME73M.
What do you mean by 'arc up' ?
news:c17ef3d9-20ec-4e4e-a4ba-0a0b2a4e7857@googlegroups.com...
Robert wrote:
I turned an empty microwave on for about 30 seconds.
What is the potential damage I have caused?
** Potentially, it can cause arcing in the wave guide leading to the oven
enclosure. Then a fuse blows.
However, most microwave ovens are immune from the effect, but makers still
advise never to do it.
I happen to own one that isn't immune, a Samsung MB245.
I cannot use it to thaw a frozen bottle of lemonade, or it arcs up.
Mine is a new Samsung ME73M.
What do you mean by 'arc up' ?
R
Robert
Guest
"Trevor Wilson" <trevor@SPAMBLOCKrageaudio.com.au> wrote in message
news:dgq4pcFsiiiU1@mid.individual.net...
When I opened the door I saw steam and a bit of 'sweating' on the inside
wall.
news:dgq4pcFsiiiU1@mid.individual.net...
On 26/01/2016 3:51 PM, Robert wrote:
I turned an empty microwave on for about 30 seconds. What is the
potential damage I have caused?
**Magnetrons take around 2 seconds to reach maximum output. So, you have
operated the magnetron for 28 seconds with no load. As others have stated,
you have probably not caused fatal damage to the magnetron (around 1
minute or more will almost certainly cause that), but you have probably
decreased the operating life of the magnetron by some amount. Damage
varies, but emission will likely be affected somewhat (probably not
noticeable). You can test the performance of the magnetron with a measured
quantity of water, an accurate thermometer and timer. Here's how (you'll
need a digital thermometer with reasonable resolution):
When I opened the door I saw steam and a bit of 'sweating' on the inside
wall.
R
Robert
Guest
"Trevor Wilson" <trevor@SPAMBLOCKrageaudio.com.au> wrote in message
news:dgq4pcFsiiiU1@mid.individual.net...
how do you know that 1 minute is the crucial time?
news:dgq4pcFsiiiU1@mid.individual.net...
On 26/01/2016 3:51 PM, Robert wrote:
I turned an empty microwave on for about 30 seconds. What is the
potential damage I have caused?
**Magnetrons take around 2 seconds to reach maximum output. So, you have
operated the magnetron for 28 seconds with no load. As others have stated,
you have probably not caused fatal damage to the magnetron (around 1
minute or more will almost certainly cause that)
how do you know that 1 minute is the crucial time?
T
Trevor Wilson
Guest
On 27/01/2016 11:45 AM, Robert wrote:
**My words (note the new emphasis):
"around 1 minute *OR MORE* will almost certainly cause that"
--
Trevor Wilson
www.rageaudio.com.au
---
This email has been checked for viruses by Avast antivirus software.
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"Trevor Wilson" <trevor@SPAMBLOCKrageaudio.com.au> wrote in message
news:dgq4pcFsiiiU1@mid.individual.net...
On 26/01/2016 3:51 PM, Robert wrote:
I turned an empty microwave on for about 30 seconds. What is the
potential damage I have caused?
**Magnetrons take around 2 seconds to reach maximum output. So, you
have operated the magnetron for 28 seconds with no load. As others
have stated, you have probably not caused fatal damage to the
magnetron (around 1 minute or more will almost certainly cause that)
how do you know that 1 minute is the crucial time?
**My words (note the new emphasis):
"around 1 minute *OR MORE* will almost certainly cause that"
--
Trevor Wilson
www.rageaudio.com.au
---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
R
Robert
Guest
"Phil Allison" <pallison49@gmail.com> wrote in message
news:66bfb608-92ae-411f-8577-ab9dcd398235@googlegroups.com...
I did hear a loud sound as soon as I switched the oven on while empty, which
is the first time I switched it on. I wouldn't be surprised if the oven is
damaged from what I did.
It seems crazy that just having the oven for a few seconds could damage it.
news:66bfb608-92ae-411f-8577-ab9dcd398235@googlegroups.com...
Robert wrote:
"Phil Allison"
** Potentially, it can cause arcing in the wave guide leading to the
oven
enclosure. Then a fuse blows.
However, most microwave ovens are immune from the effect, but makers
still
advise never to do it.
I happen to own one that isn't immune, a Samsung MB245.
I cannot use it to thaw a frozen bottle of lemonade, or it arcs up.
Mine is a new Samsung ME73M.
What do you mean by 'arc up' ?
** A few seconds after the oven is switched on, a visible and audible arc
starts up at the top of the wave guide - just behind the mica window. It
quickly burns the paint in that area and the oven must be switched off
immediately.
I did hear a loud sound as soon as I switched the oven on while empty, which
is the first time I switched it on. I wouldn't be surprised if the oven is
damaged from what I did.
It seems crazy that just having the oven for a few seconds could damage it.
R
Robert
Guest
"Phil Allison" <pallison49@gmail.com> wrote in message
news:66bfb608-92ae-411f-8577-ab9dcd398235@googlegroups.com...
I did hear a loud sound as soon as I switched the oven on while empty, which
is the first time I switched it on. I wouldn't be surprised if the oven is
damaged from what I did.
It seems crazy that just having the oven for a few seconds could damage it.
news:66bfb608-92ae-411f-8577-ab9dcd398235@googlegroups.com...
Robert wrote:
"Phil Allison"
** Potentially, it can cause arcing in the wave guide leading to the
oven
enclosure. Then a fuse blows.
However, most microwave ovens are immune from the effect, but makers
still
advise never to do it.
I happen to own one that isn't immune, a Samsung MB245.
I cannot use it to thaw a frozen bottle of lemonade, or it arcs up.
Mine is a new Samsung ME73M.
What do you mean by 'arc up' ?
** A few seconds after the oven is switched on, a visible and audible arc
starts up at the top of the wave guide - just behind the mica window. It
quickly burns the paint in that area and the oven must be switched off
immediately.
I did hear a loud sound as soon as I switched the oven on while empty, which
is the first time I switched it on. I wouldn't be surprised if the oven is
damaged from what I did.
It seems crazy that just having the oven for a few seconds could damage it.
T
Trevor Wilson
Guest
On 27/01/2016 1:13 PM, Phil Allison wrote:
**I had to replace a stirrer in a commercial MO once. A small aluminium
piece in a nylon bearing. I reckon it cost about $0.10 to manufacture.
Allowing for the usual mark-ups, I reckoned about $5.00 (trade price for
the part). Wrong. It was $240.00. I guess that's what happens when you
pay more than a grand for an MO.
--
Trevor Wilson
www.rageaudio.com.au
---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
Robert wrote:
"Phil Allison"
** Potentially, it can cause arcing in the wave guide leading to
the oven enclosure. Then a fuse blows.
However, most microwave ovens are immune from the effect, but
makers still advise never to do it.
I happen to own one that isn't immune, a Samsung MB245.
I cannot use it to thaw a frozen bottle of lemonade, or it arcs
up.
Mine is a new Samsung ME73M.
What do you mean by 'arc up' ?
** A few seconds after the oven is switched on, a visible and audible
arc starts up at the top of the wave guide - just behind the mica
window. It quickly burns the paint in that area and the oven must be
switched off immediately.
The oven originally belonged to a local café and the owners dumped
the thing on my doorstep when Samsung refused to replace it under
warranty.
Powering up a microwave with nothing inside is an everyday event in
busy cafes.
**I had to replace a stirrer in a commercial MO once. A small aluminium
piece in a nylon bearing. I reckon it cost about $0.10 to manufacture.
Allowing for the usual mark-ups, I reckoned about $5.00 (trade price for
the part). Wrong. It was $240.00. I guess that's what happens when you
pay more than a grand for an MO.
--
Trevor Wilson
www.rageaudio.com.au
---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
I
Ian Field
Guest
"Trevor Wilson" <trevor@SPAMBLOCKrageaudio.com.au> wrote in message
news:dgqimnF1cklU1@mid.individual.net...
Just for kicks - I jammed the fan on a unit with a low emission mag and run
it empty for the maximum timer duration.
I was sort of expecting something entertaining to happen - instead; the
magnetron recovered to a useable condition.
news:dgqimnF1cklU1@mid.individual.net...
On 27/01/2016 11:45 AM, Robert wrote:
"Trevor Wilson" <trevor@SPAMBLOCKrageaudio.com.au> wrote in message
news:dgq4pcFsiiiU1@mid.individual.net...
On 26/01/2016 3:51 PM, Robert wrote:
I turned an empty microwave on for about 30 seconds. What is the
potential damage I have caused?
**Magnetrons take around 2 seconds to reach maximum output. So, you
have operated the magnetron for 28 seconds with no load. As others
have stated, you have probably not caused fatal damage to the
magnetron (around 1 minute or more will almost certainly cause that)
how do you know that 1 minute is the crucial time?
**My words (note the new emphasis):
"around 1 minute *OR MORE* will almost certainly cause that"
Just for kicks - I jammed the fan on a unit with a low emission mag and run
it empty for the maximum timer duration.
I was sort of expecting something entertaining to happen - instead; the
magnetron recovered to a useable condition.
T
Trevor Wilson
Guest
On 28/01/2016 6:11 AM, Ian Field wrote:
**SWMBO decided to heat up some sesame seeds. 3 mins on high and
magnetron output was dramatically reduced. I figure that what was a 900
Watt MO was suddenly a 300 Watt MO. A magnetron swap brought it back to
new performance. Instructions were then issued to ensure adequate
quantities of food and/or water is used in future.
--
Trevor Wilson
www.rageaudio.com.au
---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
"Trevor Wilson" <trevor@SPAMBLOCKrageaudio.com.au> wrote in message
news:dgqimnF1cklU1@mid.individual.net...
On 27/01/2016 11:45 AM, Robert wrote:
"Trevor Wilson" <trevor@SPAMBLOCKrageaudio.com.au> wrote in message
news:dgq4pcFsiiiU1@mid.individual.net...
On 26/01/2016 3:51 PM, Robert wrote:
I turned an empty microwave on for about 30 seconds. What is the
potential damage I have caused?
**Magnetrons take around 2 seconds to reach maximum output. So, you
have operated the magnetron for 28 seconds with no load. As others
have stated, you have probably not caused fatal damage to the
magnetron (around 1 minute or more will almost certainly cause that)
how do you know that 1 minute is the crucial time?
**My words (note the new emphasis):
"around 1 minute *OR MORE* will almost certainly cause that"
Just for kicks - I jammed the fan on a unit with a low emission mag and
run it empty for the maximum timer duration.
I was sort of expecting something entertaining to happen - instead; the
magnetron recovered to a useable condition.
**SWMBO decided to heat up some sesame seeds. 3 mins on high and
magnetron output was dramatically reduced. I figure that what was a 900
Watt MO was suddenly a 300 Watt MO. A magnetron swap brought it back to
new performance. Instructions were then issued to ensure adequate
quantities of food and/or water is used in future.
--
Trevor Wilson
www.rageaudio.com.au
---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
T
Trevor Wilson
Guest
On 27/01/2016 5:25 PM, Robert wrote:
**Well, you're feeding something like 1.5kW into the MO, most of which
ends up being used by the magnetron. The energy has to be dissipated
somewhere. Where do you think all that energy should go?
--
Trevor Wilson
www.rageaudio.com.au
---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
"Phil Allison" <pallison49@gmail.com> wrote in message
news:66bfb608-92ae-411f-8577-ab9dcd398235@googlegroups.com...
Robert wrote:
"Phil Allison"
** Potentially, it can cause arcing in the wave guide leading to
the > oven
enclosure. Then a fuse blows.
However, most microwave ovens are immune from the effect, but
makers > still
advise never to do it.
I happen to own one that isn't immune, a Samsung MB245.
I cannot use it to thaw a frozen bottle of lemonade, or it arcs up.
Mine is a new Samsung ME73M.
What do you mean by 'arc up' ?
** A few seconds after the oven is switched on, a visible and audible
arc starts up at the top of the wave guide - just behind the mica
window. It quickly burns the paint in that area and the oven must be
switched off immediately.
I did hear a loud sound as soon as I switched the oven on while empty,
which is the first time I switched it on. I wouldn't be surprised if
the oven is damaged from what I did.
It seems crazy that just having the oven for a few seconds could damage it.
**Well, you're feeding something like 1.5kW into the MO, most of which
ends up being used by the magnetron. The energy has to be dissipated
somewhere. Where do you think all that energy should go?
--
Trevor Wilson
www.rageaudio.com.au
---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
I
Ian Field
Guest
"Trevor Wilson" <trevor@SPAMBLOCKrageaudio.com.au> wrote in message
news:dgsp74Fic3lU1@mid.individual.net...
Drawing that much power from the mains usually only gets you about 700 -
800W of cooking power. Half of it produces heat anyway.
Apparently the potential for damage is in standing waves and reflections
within the cooking compartment. There's usually some form of pin-bearing
light alloy vanes to scatter the beam and constantly vary the "mode" - so
its pretty random anyway whether the waves will be reflected directly back
into the waveguide.
With a big fat turkey in there, all the waves get absorbed - in theory
anyway.
news:dgsp74Fic3lU1@mid.individual.net...
On 27/01/2016 5:25 PM, Robert wrote:
"Phil Allison" <pallison49@gmail.com> wrote in message
news:66bfb608-92ae-411f-8577-ab9dcd398235@googlegroups.com...
Robert wrote:
"Phil Allison"
** Potentially, it can cause arcing in the wave guide leading to
the > oven
enclosure. Then a fuse blows.
However, most microwave ovens are immune from the effect, but
makers > still
advise never to do it.
I happen to own one that isn't immune, a Samsung MB245.
I cannot use it to thaw a frozen bottle of lemonade, or it arcs up.
Mine is a new Samsung ME73M.
What do you mean by 'arc up' ?
** A few seconds after the oven is switched on, a visible and audible
arc starts up at the top of the wave guide - just behind the mica
window. It quickly burns the paint in that area and the oven must be
switched off immediately.
I did hear a loud sound as soon as I switched the oven on while empty,
which is the first time I switched it on. I wouldn't be surprised if
the oven is damaged from what I did.
It seems crazy that just having the oven for a few seconds could damage
it.
**Well, you're feeding something like 1.5kW into the MO, most of which
ends up being used by the magnetron. The energy has to be dissipated
somewhere. Where do you think all that energy should go?
Drawing that much power from the mains usually only gets you about 700 -
800W of cooking power. Half of it produces heat anyway.
Apparently the potential for damage is in standing waves and reflections
within the cooking compartment. There's usually some form of pin-bearing
light alloy vanes to scatter the beam and constantly vary the "mode" - so
its pretty random anyway whether the waves will be reflected directly back
into the waveguide.
With a big fat turkey in there, all the waves get absorbed - in theory
anyway.