sci.electronics.repair - 25 new messages in 8 topics - digest

sci.electronics.repair
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Today's topics:

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TOPIC: TV picture distorted
http://groups.google.com/group/sci.electronics.repair/t/ec61658f4376abe1?hl=en
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== 1 of 2 ==
Date: Wed, Jan 19 2011 12:59 am
From: "PE"

Why ask a question to which you obviously already know the answer? What's
your point?

<hrhofmann@att.net> wrote in message
news:0a9046ac-8c12-4177-ad07-e964ed085da3@t23g2000vby.googlegroups.com...
> On Jan 17, 1:10 am, "``ZACK``" <youwillfine...@home.com.au> wrote:
>> "PE" <p...@ix.netcom.com> wrote in message
>>
>> news:_PednQsdJv8fOK7QnZ2dnUVZ_tOdnZ2d@earthlink.com...> Hi all: My 15-yr
>> old Toshiba 27" crt television has recently developed a
>> > problem which is that approx 15 minutes after being turned on, the
>> > picture
>> > bows inward on the left and right sides. Then, after a few more
>> > minutes,
>> > the picture resolves and returns to normal and remains perfect for the
>> > remaining time the tv is on. If the symptom described above means the
>> > crt
>> > is wearing out, so be it, the set will soon be history. However, I'm
>> > wondering whether some other, replaceable part, might be going bad and
>> > causing the temporarily distorted picture.
>>
>> > Would appreciate any suggestions re. probable cause(s) of symptom
>> > described above. Am basically novice, but handy and with soldering
>> > skills, and have done a few simple tv repairs in the past. Thanks for
>> > your replies!
>>
>> horizontal coupling cap
>> faulty yoke
>> or flyback tranformer circuit
>> pincushion transformer circuit
>> or try
>> herehttp://www.devileye.net/catalog/boiling_liquefied_gas/side_pincushion...
>>
>> orhttp://www.google.com.au/search?hl=en&client=firefox-a&hs=bCP&rls=org...
>
> DIdn't you get enough relies on alt.home.repair????
>

== 2 of 2 ==
Date: Wed, Jan 19 2011 2:31 am
From: "Phil Allison"

"PE"
>
> Why ask a question to which you obviously already know the answer? What's
> your point?

** The only questions really worth asking someone are ones where you * know
* what the answer is.

Think about it.....

..... Phil

==============================================================================
TOPIC: Reduce power of a microwave oven?
http://groups.google.com/group/sci.electronics.repair/t/76e6c7ef368fc8a0?hl=en
==============================================================================

== 1 of 10 ==
Date: Wed, Jan 19 2011 2:03 am
From: "Wild_Bill"

Your easiest solution may be to look for a new model that has the cooking
power levels that suit your needs.
I haven't looked at MWOs lately, but the revolving turntable should probably
be a major consideration.

From many years ago, I found that trying to cook numerous types of foods in
a microwave provided awful results, and never bothered to try them in more
advanced models.
Bacon, eggs, burger were some examples.

The fairly large MWO I use now was given to me a number of years ago, and
suits my needs for the types of foods that I want to be microwaved.
The manual has so many different types of cycles, that I don't even bother
to try to remember them.
I stick with the basic operations, which limits what the MWO will be used
for, but that's not a problem for me.

Typical MWOs aren't a good substitute for an actual range/stove (and
appropriate cookware, talent, time etc).
Also, one generally needs to find the types/brands of processed foods that
provide the user with something desirable to their own tastes.

The top crust of a pot pie should be browned.. the Marie Callendar(?) frozen
pies have a metallic grid made into the top of the box, and the crust always
browns (may not work with low-powered MWOs, I don't know for sure). The
minimum power recommended is marked on the box.
The 1 lb size pies are a decent portion, and taste good.. allow ample time
for cooling.

I don't have them anymore, but at one time I had a set of microwave dishes
with covers that were very useful.
They were a tan bakelite/melmac-type material with metal flakes visible in
the material.. they were a fairly common brand name in the U.S. but I'm not
sure what it was.
Anyway, I could get varied results with lid on , off or turned 45 degrees
(square dishes), which are all common techniques with conventional cooking.
So, the types of accessories and different techniques will yield more
options, and very different results.

I've found certain techniques that produce results which are more to my
personal liking.. such as always wrap/cover a sandwich in paper towel to
heat (prevents the bread/bun from getting hard spots without becoming
soggy), cover cold pizza also with paper towel, or better yet, eat it cold.
There are various options.. placing flat foods between two paper plates, or
tall sandwiches between two paper bowls.
There are various commercial plastic products/accessories for MWO use, but
those require washing.. disposable paper (not plastic/styrofoam) plates and
bowls, and plastic utensils don't.

I never put uncovered liquids or other types of foods that are a combination
of food/liquid in the MWO, I always use a paper plate as a cover. I can't
stand seeing a dirty MWO, and it's far easier to prevent eruptions than to
clean them up.
But then, I generally always wipe the interior down with a paper towel
dampened with 60/40% water/alcohol mixture that has a few drops of liquid
soap added per pint, to wipe out the condensed moisture, every time I use
the MWO.

--
Cheers,
WB
.............

"mike" <spamme9@gmail.com> wrote in message
news:ih536g$rco$1@news.eternal-september.org...
> My 27 year old microwave oven was down below 400W output and taking a long
> time to heat my coffee.
> So, I went out and bought a 1100W one.
> Big mistake.
> It works fine on coffee, but WAY overcooks small stuff.
> Yes, it has a power level setting, but the on-time is 15 seconds
> and they modulate the off-time.
> I tried to heat a frozen hamburger patty. It boils the liquid around
> the outside for 15 seconds, but the inside is still frozen.
> This really messes up the cheese stuck to it. If I leave it in
> the frozen burger, it comes out awful.
>
> What are my options for reducing power?
> Yes, I can stick in a pot of water to absorb energy, but I'm
> looking for a more elegant solution.
> I assume there's nothing I can do on the primary side, cause of the
> filament voltage requirements.
> Assuming I can find a switch that can take the voltage and current,
> can I switch the value of the big cap? Not much else in there to play
> with.
>
> Alternatively, there's stuff they put in the bottom of microwave popcorn
> that heats up from microwaves. What is that stuff? Maybe I can find a
> pan with that in the bottom to average out the energy over time.
> There's a "as seen on TV" serving plate that you heat in the microwave.
> It's made of granite. What is it in the granite that gets heated?
> IF I could find a square of floor tile in ceramic or granite, ceramic is
> more easily available, I could stick one of them in the bottom of the
> oven.
>
> Suggestions?
> Thanks, mike

== 2 of 10 ==
Date: Wed, Jan 19 2011 5:41 am
From: PeterD

On Tue, 18 Jan 2011 20:35:49 -0500, "Michael A. Terrell"
<mike.terrell@earthlink.net> wrote:

>
>mike wrote:
>>
>> My 27 year old microwave oven was down below 400W output and taking a long
>> time to heat my coffee.
>> So, I went out and bought a 1100W one.
>> Big mistake.
>> It works fine on coffee, but WAY overcooks small stuff.
>> Yes, it has a power level setting, but the on-time is 15 seconds
>> and they modulate the off-time.
>> I tried to heat a frozen hamburger patty. It boils the liquid around
>> the outside for 15 seconds, but the inside is still frozen.
>> This really messes up the cheese stuck to it. If I leave it in
>> the frozen burger, it comes out awful.
>>
>> What are my options for reducing power?
>> Yes, I can stick in a pot of water to absorb energy, but I'm
>> looking for a more elegant solution.
>> I assume there's nothing I can do on the primary side, cause of the
>> filament voltage requirements.
>> Assuming I can find a switch that can take the voltage and current,
>> can I switch the value of the big cap? Not much else in there to play with.
>>
>> Alternatively, there's stuff they put in the bottom of microwave popcorn
>> that heats up from microwaves. What is that stuff? Maybe I can find a
>> pan with that in the bottom to average out the energy over time.
>> There's a "as seen on TV" serving plate that you heat in the microwave.
>> It's made of granite. What is it in the granite that gets heated?
>> IF I could find a square of floor tile in ceramic or granite, ceramic is
>> more easily available, I could stick one of them in the bottom of the oven.
>>
>> Suggestions?
>
>
> RTFM to see how to set the cook power.

Or use the defrost cycle!

== 3 of 10 ==
Date: Wed, Jan 19 2011 5:55 am
From: "William Sommerwerck"

>> Can you return the oven? You can use the argument
>> that it's not fit for its intended purpose. Which it isn't.

> Nope, my inability to forecast the consequences is not
> the fault of the seller.

If your description is correct, the oven is grossly misdesigned. You do not
implement variable power by turning the magenetron on for 15 seconds, then
letting it sit for a minute! I've /never/ seen a microwave oven that works
that way. My home GE works fine, as do all those I've seen where I've
worked.

>> I always assumed variable power was simple duty-cycle variation --
>> pulse-width-modulation -- over a fraction of a second. That the "on" time
>> would be fixed at 15 seconds (!!!), with the off time varied, is absurd.
It
>> would produce exactly the effect you see.

> Yep, that's the way most of 'em work. The problem is the filament in
> the magnetron. Much shorter and you don't get any power out cause
> the filament ain't hot yet. With enough mass inside the oven, it
> averages out pretty well. For a single frozen hamburger at 1100W, not
> so much.

I've never heard of varying a magnetron's power by adjusting its filament
voltage! I've always ASS+U+MEd there was some way of turning the tube on and
off by varying an electrode voltage. (Simply pulsing the anode voltage would
produce variable output.)

== 4 of 10 ==
Date: Wed, Jan 19 2011 5:57 am
From: "William Sommerwerck"

> Bacon, eggs, burger were some examples.

A microwave oven is ideal for bacon, because all it needs is a thorough
heating. Which is all a microwave oven does... It doesn't actully /cook/
anything.

== 5 of 10 ==
Date: Wed, Jan 19 2011 6:39 am
From: Lab1 <.@...>

On 1/19/2011 2:07 AM, Fred McKenzie wrote:

>> Yes, it has a power level setting, but the on-time is 15 seconds
>> and they modulate the off-time.
>> I tried to heat a frozen hamburger patty. It boils the liquid around
>> the outside for 15 seconds, but the inside is still frozen.

>
> Does the new microwave have a Defrost option? If so, does it also cook
> for 15 seconds at full power?

Many new microwaves have and auto-defrost function (also usually an
auto-reheat) that measures the humidity while firing the magnetron for
short bursts. It runs this cyclically for a preset time based on your
food selection and weight while it calculates the actual time it should
take to defrost the food. Then it usually beeps once and finally runs
the defrost cycle that it calculated.

I find this works quite well once you get the hang of it.

--
-Scott

== 6 of 10 ==
Date: Wed, Jan 19 2011 8:27 am
From: "Arfa Daily"

"William Sommerwerck" <grizzledgeezer@comcast.net> wrote in message
news:ih6qf4$6sk$1@news.eternal-september.org...
>>> Can you return the oven? You can use the argument
>>> that it's not fit for its intended purpose. Which it isn't.
>
>> Nope, my inability to forecast the consequences is not
>> the fault of the seller.
>
> If your description is correct, the oven is grossly misdesigned. You do
> not
> implement variable power by turning the magenetron on for 15 seconds, then
> letting it sit for a minute! I've /never/ seen a microwave oven that works
> that way. My home GE works fine, as do all those I've seen where I've
> worked.
>
>
>>> I always assumed variable power was simple duty-cycle variation --
>>> pulse-width-modulation -- over a fraction of a second. That the "on"
>>> time
>>> would be fixed at 15 seconds (!!!), with the off time varied, is absurd.
> It
>>> would produce exactly the effect you see.
>
>> Yep, that's the way most of 'em work. The problem is the filament in
>> the magnetron. Much shorter and you don't get any power out cause
>> the filament ain't hot yet. With enough mass inside the oven, it
>> averages out pretty well. For a single frozen hamburger at 1100W, not
>> so much.
>
> I've never heard of varying a magnetron's power by adjusting its filament
> voltage! I've always ASS+U+MEd there was some way of turning the tube on
> and
> off by varying an electrode voltage. (Simply pulsing the anode voltage
> would
> produce variable output.)
>
>

All of the bog-standard microwave ovens that I've owned have worked exactly
like that - and it was fine when they were the 'standard' 600 or 650 watts
of a few years ago. However, now they are all 850 / 900 / 1000 watts, it's a
crap system of power control. The one I have at the moment, does exactly as
the poster's does when set to say 60% power. It's like 15 seconds on at full
chat, followed by 20 seconds at full off. 60% is what's needed for heating a
can of soup in a reasonable time to a reasonable temperature. And it's ok if
it's just a full liquid soup like say tomato. But as soon as you try to do
it with anything like perhaps vegetable, 15 seconds of microwaves at 850
watts, is enough to start exploding the peas or beans or barley grains, all
over the inside of the rotten thing. 600 watts didn't used to do this. If
you go to the next step down - ie 40% power - it takes forever to get the
bulk liquid of the soup up to an edible temperature.

Arfa

== 7 of 10 ==
Date: Wed, Jan 19 2011 8:36 am
From: "Arfa Daily"

"William Sommerwerck" <grizzledgeezer@comcast.net> wrote in message
news:ih6qji$7hl$1@news.eternal-september.org...
>> Bacon, eggs, burger were some examples.
>
> A microwave oven is ideal for bacon, because all it needs is a thorough
> heating. Which is all a microwave oven does... It doesn't actully /cook/
> anything.
>
>

I seem to remember that we had this discussion once before some years back.
It depends on how you define the word "cook". Using the traditional
definition of 'preparing food by use of heat' I would contend that this is
exactly what a microwave oven does - or am I missing something ... ? If I
am, then what *is* cooking that a conventional oven does differently ?

Arfa

== 8 of 10 ==
Date: Wed, Jan 19 2011 9:16 am
From: "William Sommerwerck"

> All of the bog-standard microwave ovens that I've owned have worked
exactly
> like that - and it was fine when they were the 'standard' 600 or 650 watts
> of a few years ago. However, now they are all 850 / 900 / 1000 watts, it's
a
> crap system of power control. The one I have at the moment, does exactly
as
> the poster's does when set to say 60% power. It's like 15 seconds on at
full
> chat, followed by 20 seconds at full off. 60% is what's needed for heating
a
> can of soup in a reasonable time to a reasonable temperature. And it's ok
if
> it's just a full liquid soup like say tomato. But as soon as you try to do
> it with anything like perhaps vegetable, 15 seconds of microwaves at 850
> watts, is enough to start exploding the peas or beans or barley grains,
all
> over the inside of the rotten thing. 600 watts didn't used to do this. If
> you go to the next step down - ie 40% power - it takes forever to get the
> bulk liquid of the soup up to an edible temperature.

Fascinating. (In the correct Spock sense... "Fascinating I reserve for the
unexpected.")

I have a high-power GE microwave oven cum exhaust hood. Many foods -- such
as soup or oatmeal -- must be heated at half power (give or take), or you
get localized boiling, sometimes very quickly. I've never seen this happen
with reduced power. The oven always acts as if the magnetron is being
rapidly pulsed.

May I publicly apologize for believing that manufacturers ever use the least
bit of common sense when designing products?

== 9 of 10 ==
Date: Wed, Jan 19 2011 9:24 am
From: "William Sommerwerck"

"Arfa Daily" <arfa.daily@ntlworld.com> wrote in message
news:7qEZo.371$S16.147@newsfe20.ams2...
> "William Sommerwerck" <grizzledgeezer@comcast.net> wrote in message
> news:ih6qji$7hl$1@news.eternal-september.org...

>>> Bacon, eggs, burger were some examples.

>> A microwave oven is ideal for bacon, because all it needs is a thorough
>> heating. Which is all a microwave oven does... It doesn't actully /cook/
>> anything.

> I seem to remember that we had this discussion once before some
> years back. It depends on how you define the word "cook". Using the
> traditional definition of 'preparing food by use of heat' I would contend
> that this is exactly what a microwave oven does - or am I missing
> something ... ? If I am, then what *is* cooking that a conventional
> oven does differently ?

Your perfectly logical definition seems sufficiently generic to include
microwave ovens. In practice, "cooking" refers to either immersing
the-thing-to-be-prepared in a cavity full of hot air...

"Yeah, Sommerwerck -- yer mouth."

...(baking, roasting) or applying heat directly to it (frying) or from a
nearby source (broiling, grilling). Microwave "cooking" does none of
these -- it simply heats the-thing-to-be-prepared from the inside.

Oddly, the Wikipedia article claims that microwave cooking heats food more
evenly than any other method, when, in fact, it heats from the outside in,
as does every other cooking method, and can be extremely uneven, if part of
the dish is sitting in a standing-wave node.

== 10 of 10 ==
Date: Wed, Jan 19 2011 9:42 am
From: "William Sommerwerck"

Here, for example, is a patent for pulsed control of microwave-oven power.
It was filed for in 1975.

http://ip.com/patent/US4041267

==============================================================================
TOPIC: LATEST HOT PICS &VIDEOS
http://groups.google.com/group/sci.electronics.repair/t/2168fae3a534669a?hl=en
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== 1 of 1 ==
Date: Wed, Jan 19 2011 2:36 am
From: SRAVANTHI LOVE

==============================================================================
TOPIC: How to repair an invisible machine from the 23rd century?
http://groups.google.com/group/sci.electronics.repair/t/e431feeea64c740f?hl=en
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== 1 of 4 ==
Date: Wed, Jan 19 2011 2:44 am
From: Jeff Urban

You people of the past know nothing.

Pick up a T factor chip for the SW7 (you DO have an SW7 I hope) and
install it. Then you simply go back in time and prevent the occurance
of the faualt. Make sure to use VF9 antigrator so you are not affected
by the timeline. Sorry about your family, but you can write a nice
hefty repair bill on that. I mean 35,890 KW of energy and all that.
You migtht have to do a bit of customer relations to make them
understand that this awesome power does not grow on trees.

Terminator four.

== 2 of 4 ==
Date: Wed, Jan 19 2011 3:50 am
From: Bob Villa

On Jan 18, 1:40 pm, "Lloyd Hearsewave" <sore_prin...@yahoo.com> wrote:
> I've found an invisible machine from the 23rd century, but it's not working.
>
> How can I repair it?

If you don't know what it does...why would you repair it? How do you
know its timeline if you can't see it?

== 3 of 4 ==
Date: Wed, Jan 19 2011 5:39 am
From: "Geoffrey S. Mendelson"

Bob Villa wrote:
> If you don't know what it does...why would you repair it? How do you
> know its timeline if you can't see it?

Wasn't there a Star Trek Next Generation episode about this? A person from
the 22nd century found a time machine, went forward into the 24th and claimed
to be a historian. He was actually collecting artifacts to take back 200 years
and sell off the technology.

Geoff.

--
Geoffrey S. Mendelson N3OWJ/4X1GM
Those who cannot remember the past are condemned to misquote it.

== 4 of 4 ==
Date: Wed, Jan 19 2011 6:45 am
From: Lab1 <.@...>

On 1/18/2011 2:40 PM, Lloyd Hearsewave wrote:
> I've found an invisible machine from the 23rd century, but it's not working.
>
> How can I repair it?

Spray paint it so you can see what broke.

--
-Scott

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TOPIC: Pet hates ?
http://groups.google.com/group/sci.electronics.repair/t/e7925b5c2233e9ec?hl=en
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== 1 of 5 ==
Date: Wed, Jan 19 2011 6:54 am
From: "N_Cook"

Great dollops of that white goo between metal to metal thermally conductive
surfaces. Heatsink to metal casing in amplifiers etc. I'm not sure why it is
even necessary with perhaps 20 square inches of contact and bolts between. I
always wipe away with paper etc on first parting but always some gets on my
clothing - I've not worn white lab coats for many a year.

== 2 of 5 ==
Date: Wed, Jan 19 2011 7:04 am
From: Lab1 <.@...>

On 1/19/2011 9:54 AM, N_Cook wrote:
> Great dollops of that white goo between metal to metal thermally conductive
> surfaces. Heatsink to metal casing in amplifiers etc. I'm not sure why it is
> even necessary with perhaps 20 square inches of contact and bolts between. I
> always wipe away with paper etc on first parting but always some gets on my
> clothing - I've not worn white lab coats for many a year.

Heat sink compound is usually very necessary.

One of my pet hates is torx screws with a pin in the center.

== 3 of 5 ==
Date: Wed, Jan 19 2011 8:17 am
From: "Arfa Daily"

"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ih6u0j$hqi$1@news.eternal-september.org...
> Great dollops of that white goo between metal to metal thermally
> conductive
> surfaces. Heatsink to metal casing in amplifiers etc. I'm not sure why it
> is
> even necessary with perhaps 20 square inches of contact and bolts between.
> I
> always wipe away with paper etc on first parting but always some gets on
> my
> clothing - I've not worn white lab coats for many a year.
>
>

Me and white heatsink goo have a very bad working relationship. I only have
to walk into the workshop when there's something on the bench using it, and
all of a sudden, I'm covered in the rotten stuff, without even going near
the bench. At least it seems that way ... :-\

Arfa

== 4 of 5 ==
Date: Wed, Jan 19 2011 8:39 am
From: "N_Cook"

Lab1 <.@...> wrote in message
news:ih6ugq$mee$1@news.eternal-september.org...
> On 1/19/2011 9:54 AM, N_Cook wrote:
> > Great dollops of that white goo between metal to metal thermally
conductive
> > surfaces. Heatsink to metal casing in amplifiers etc. I'm not sure why
it is
> > even necessary with perhaps 20 square inches of contact and bolts
between. I
> > always wipe away with paper etc on first parting but always some gets on
my
> > clothing - I've not worn white lab coats for many a year.
>
> Heat sink compound is usually very necessary.
>
> One of my pet hates is torx screws with a pin in the center.
>

The harware that I always have problems with in the UK , never organised a
stock of, is UNF and UNC nuts and bolts for USA kit. And of course,vice
versa, repairers in USA never have metric (and lesser extent BA) for UK and
Japanese kit

== 5 of 5 ==
Date: Wed, Jan 19 2011 9:24 am
From: "William Sommerwerck"

Poodles.

==============================================================================
TOPIC: Denon AVR 4308
http://groups.google.com/group/sci.electronics.repair/t/cd951501a407d472?hl=en
==============================================================================

== 1 of 1 ==
Date: Wed, Jan 19 2011 8:13 am
From: "Arfa Daily"

Anyone got a copy of the service manual for this monster AV amp ? Looks like
the supply to the DSP board is missing, but the PSU regulator board is a
'daughter' from the main board, and a bit buried, so not easy to work on,
removed. Just need a copy of the schematic for the power supply and
regulators, so I can confirm that the supply is missing, and see exactly
where it comes from. Might then stand a chance of fixing it 'cold'.

TIA

Arfa

==============================================================================
TOPIC: Repair or replacing a GE Spacemaker Microwave?
http://groups.google.com/group/sci.electronics.repair/t/c1d6b4bd44bdd1d7?hl=en
==============================================================================

== 1 of 1 ==
Date: Wed, Jan 19 2011 9:55 am
From: BSAKing

I have one of these guys and it has served me very well for probably
15+ years, so I have no quarrel with it.

From the manual, the model number is a JVM 250 BVC or JVM 250 WVC
(probably a white or black model).

In any event, this morning old Betsy decided not to heat anything up.
All the bells and whistles are there, fan runs, etc, lights action,
keypad works, just no heat. So I suspect more than likely the
magnetron or xformer.

I was wondering if anyone knows if there is a secondary fuse I could
check on this model before I turf it? Obviously main one is good as
everything else powers on.

The second question is that I remember installing this thing and
having to adapt a hole in the wall to an outside vent etc to fit it. I
am hoping that maybe a new model of the same make would have roughly
the same vent location so I do not have to rebuild that part to put in
a new one.

Or maybe it is standard for all microwaves? Does anyone know?

Any clues or input appreciated.

TIA, BSA

==============================================================================
TOPIC: Simple Question about Thermal Cutoff (tco) & Fuses
http://groups.google.com/group/sci.electronics.repair/t/9522848ef646160c?hl=en
==============================================================================

== 1 of 1 ==
Date: Wed, Jan 19 2011 9:55 am
From: j barnes

On Jan 18, 6:19 pm, Jim Yanik <jya...@abuse.gov> wrote:
> Fred McKenzie <fm...@aol.com> wrote innews:fmmck-007CC7.23000717012011@5ad64b5e.bb.sky.com:
>
>
>
>
>
>
>
>
>
> > In article
> ><65201db0-66d6-46b9-be6d-67de7495a...@glegroupsg2000goo.googlegroups.com
> >>,
> > j barnes <slywink...@gmail.com> wrote:
>
> >> Would it be safe for me to replace the 4AMPTCOwith a 10amp 152C and
> >> simply add a 4ampfuseimmediately before or after theTCO?
>
> > JB-
>
> > I can't imagine the tea kettle cost much over $30, so it is not cost
> > effective to buy the exact part. The price appears to be calculated
> > to encourage you to buy a new samovar instead of repairing yours.
>
> > From where did you obtain the specifications for the original part?
> > What are the samovar's electrical ratings for voltage and power? They
> > may be on the bottom or next to the electrical wire.
>
> > Several coffee makers I checked all use power in the 600 to 800 watt
> > range. If the samovar operates close to 480 watts (4 Amperes at 120
> > Volts), you would not want thefuseto blow at 4 Amperes. I suspect
> > the function of the original part was to protect against a fire when
> > the pot was operated after all the liquid had boiled away. So the 4
> > Ampere rating is a maximum operating current, not necessarily the
> > current at which it blows.
>
> > How were you going to install the replacement? Soldering is not a
> > good idea. Solder could melt under normal operating conditions, and
> > soldering might damage theTCOif you aren't careful. Crimping is the
> > better approach, but it is difficult to get a good crimp with solid
> > wires. Some TCOs come with a "crimping ferrule". It is a small metal
> > tube (brass?) that you insert two wires into and crimp them together.
>
> > Fred
>
> I have a Presto Fry Granddaddy deep fryer that theTCOblew when the
> bimetal thermostat contacts welded together. AFAIK,they don't make the
> Grandaddy anymore,so I unstuck and filed the contacts,then bought a newTCO
> at Radio Shack !! that was a few deg C lower than the original,but same
> current rating.It's been working fine ever since. I bought new crimp
> ferrules at Skycraft Surplus.(local store,Orlando,FL.!)
>
> --
> Jim Yanik
> jyanik
> at
> localnet
> dot com

Thank you everyone for all the helpful advice and suggestions! I'm
glad everyone reminded me to crimp rather than solder. I can be a
real space case when I get caught up in repairs so it was a great
reminder.

For the curious, the $30 part is for a $170+ Samovar so I don't think
they are trying to force a new sale. It is hoity-toity expensive
German made samovar used for shi-shi-fu-fu parties. Looking at the
thing, I would have never guessed somebody would pay so much for it.
I'm certain it cost a fraction of what it sold for to make it and
there were dozens of happy people along the chain of sale between
Germany and here who tacked on a nice healthy profit for themselves.

Personally, I'm the kind of dude who would bust out with my trusty
decades old plastic coffee-stained Mr. Coffee or my newer Proctor
Silex tea kettle if I need quick boiling water, if my friends don't
respect me because of that they aren't my friends. However, this is
the female species I am dealing with here. Such uncouthness as mine
displayed by the hostess who is requesting the repair would bring many
years of shame and embarrassment on her family for generations to
come.

Of course I'm just kidding about the shame and embarrassment lasting
for generations, but this repair is bound up in culture and psuedo-
sophistication rather than pure utility.

Thanks again!

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