Hi Friends

Someone plugged my Dream machine (rated 110 VAC) into a 220 VAC outlet
and the transformer primary got trashed. Since I will be living here
for a while I thought of getting a transformer made here locally (very
cheap, honest).

There are two independent secondaries and will thank anyone who can
tell me what the outputs are.

--
Thanks for your time and attention

Ardent

On Sep 9, 7:52*pm, Ardent wrote:
Hi Friends

Someone plugged my Dream machine (rated 110 VAC) into a 220 VAC outlet
and the transformer primary got trashed. Since I will be living here
for a while I thought of getting a transformer made here locally (very
cheap, honest).

There are two independent secondaries and will thank anyone who can
tell me what the outputs are.

--
Thanks for your time and attention

Ardent

WHoever sells the transformer should know!!!!!!

Ardent wrote:

Hi Friends

Someone plugged my Dream machine (rated 110 VAC) into a 220 VAC outlet
and the transformer primary got trashed. Since I will be living here
for a while I thought of getting a transformer made here locally (very
cheap, honest).

There are two independent secondaries and will thank anyone who can
tell me what the outputs are.

Well, I couldn't tell you exactly except for, I bet they are rated
for half of what was put into it!

And, what the hell is a Dream Machine? Sounds a little kinky!


http://webpages.charter.net/jamie_5"

Contact Sony and ask them who their parts distributor is for your
area. Also find out who does their authorised service in your area.

In the worse case you will have to put in the original transformer.
Then you get an external transformer that can step down the 220 VAC to
120 VAC for your unit. Make sure that the wattage rating of the step
down is at least a minimum of 40% to 60% greater than the wattage
rating of the unit that it is going to be connected to.

For the step down, just make sure you get a proper transformer and not
one of these small low cost electronic thrystor types. The electronic
type of step down will damage the transformer in your unit.


Jerry G.

--


On Sep 9, 8:52*pm, Ardent wrote:
Hi Friends

Someone plugged my Dream machine (rated 110 VAC) into a 220 VAC outlet
and the transformer primary got trashed. Since I will be living here
for a while I thought of getting a transformer made here locally (very
cheap, honest).

There are two independent secondaries and will thank anyone who can
tell me what the outputs are.

--
Thanks for your time and attention

Ardent

"Ardent" wrote in message
...
Hi Friends

Someone plugged my Dream machine (rated 110 VAC) into a 220 VAC outlet
and the transformer primary got trashed. Since I will be living here
for a while I thought of getting a transformer made here locally (very
cheap, honest).

There are two independent secondaries and will thank anyone who can
tell me what the outputs are.

--
Thanks for your time and attention

Ardent

The primary of the transformer being trashed, might very well be the least
of your worries. Power transformers are pretty robust, and it is likely that
the primary survived for at least some tens of miliseconds before failing,
and possibly more than that. This means that for this period, the secondary
voltages will have been double their nominal value, which could have done
rather more serious downstream damage ...

Sorry to throw this one in, but it's a problem that we see fairly regularly
in the UK with visitors from the US, and often they think it is just going
to be a simple power problem like a fuse, and it turns out to be rather more
serious. You might be one of the lucky ones and have gotten away with it.
Let's hope :-)

Arfa

For the step down, just make sure you get a proper transformer
and not one of these small low cost electronic thrystor types.
The electronic type of step down will damage the transformer
in your unit.

These are not transformers. They're more like a lamp dimmer.

The person rebuilding the transformer (should it come to that) might be able
to rewind for 220V.

Hi!

And, what the hell is a Dream Machine? Sounds a little kinky!

It's an alarm clock sold by Sony. There's nothing special about it--most of
them are just AM/FM radios with a digital clock built in.

Oh, and some of them call the snooze button a "dream bar".

William

On Wed, 10 Sep 2008 06:22:48 +0530, Ardent
wrote:

Someone plugged my Dream machine (rated 110 VAC) into a 220 VAC outlet
and the transformer primary got trashed. Since I will be living here
for a while I thought of getting a transformer made here locally (very
cheap, honest).

Well, thanks to all of you for responding, though I got no useful
information. I said I am in a 220 VAC area so I thought of getting a
new 220 VAC transformer made to avoid using a step down transformer at
the same time eliminate the accident repeat in future.

I can always get a spare (110 VAC one) when I return home.

--
Thanks for your time

Ardent

In article ,
Ardent wrote:
Someone plugged my Dream machine (rated 110 VAC) into a 220 VAC outlet
and the transformer primary got trashed. Since I will be living here
for a while I thought of getting a transformer made here locally (very
cheap, honest).

I'm willing to bet it's rather more than just the transformer. Copper
takes time to melt while solid state destructs near instantly.

--
*Why isn't 11 pronounced onety one? *

Dave Plowman London SW
To e-mail, change noise into sound.

"Dave Plowman (News)" wrote:

In article ,
Ardent wrote:
Someone plugged my Dream machine (rated 110 VAC) into a 220 VAC outlet
and the transformer primary got trashed. Since I will be living here
for a while I thought of getting a transformer made here locally (very
cheap, honest).

I'm willing to bet it's rather more than just the transformer. Copper
takes time to melt while solid state destructs near instantly.


You are ignoring core saturation. That limits the maximum voltage on
the secondary. I have replaced several 120 VAC transformers that opened
when plugged into 240 VAC and had no problems with the electronics. You
aren't always lucky, but if it is a typical cheap as possible
transformer it will die first.


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There are two kinds of people on this earth:
The crazy, and the insane.
The first sign of insanity is denying that you're crazy.

"Dave Plowman (News)" wrote in message
...
In article ,
Ardent wrote:

Someone plugged my Dream machine (rated 110 VAC) into a 220
VAC outlet and the transformer primary got trashed. Since I will be
living here for a while I thought of getting a transformer made here
locally (very cheap, honest).

I'm willing to bet it's rather more than just the transformer. Copper
takes time to melt while solid state destructs near instantly.

Agreed. The fact the transformer was damaged -- which likely doesn't occur
instantly -- suggests that at least a few parts in the power supply let out
their life-giving smoke.

You are ignoring core saturation. That limits the maximum voltage
on the secondary.

But wouldn't that require enough current draw to saturate? Or are you
arguing that the transformer is so cheap that it normally operates close to
saturation, anyway?

"William Sommerwerck" wrote in message
. ..
"Dave Plowman (News)" wrote in message
...
In article ,
Ardent wrote:

Someone plugged my Dream machine (rated 110 VAC) into a 220
VAC outlet and the transformer primary got trashed. Since I will be
living here for a while I thought of getting a transformer made here
locally (very cheap, honest).

I'm willing to bet it's rather more than just the transformer. Copper
takes time to melt while solid state destructs near instantly.

Agreed. The fact the transformer was damaged -- which likely doesn't occur
instantly -- suggests that at least a few parts in the power supply let
out
their life-giving smoke.



I see small transformers like this fry very quickly with double voltage
applied. Happens all the time here in the US when the neutral lifts. Most
often that is all that is wrong, though I'll admit that does sound
surprising.

Mark Z.

William Sommerwerck wrote:

You are ignoring core saturation. That limits the maximum voltage
on the secondary.

But wouldn't that require enough current draw to saturate? Or are you
arguing that the transformer is so cheap that it normally operates close to
saturation, anyway?


Most cheap consumer items that I've looked at are so close to
saturation that their transformers start to saturate & overheat at less
than 20% over the rated voltage. I have seen some with less than a 10%
margin. Even worse, the cheap *******s didn't use a thermal fuse in the
core or metal bells for fire protection, and set the plastic cases on
fire. I had to locate & replace hundreds of substandard transformers a
service center installed in some old Jerrold/ General Instruments
JRX3/JSX3 Cable TV boxes. Luckily, the rest of their work was just as
shoddy, and all but a half dozen were back in the shop before they
caught fire out of over 8000 that were in service.

It isn't hard to test for saturation. A variac, a low voltage lamp
that is close to the primary current, and a scope across the secondary.
Slowly bring the input voltage up, until the output starts to flat top,
and read the input voltage. The lamp will light, or burn out if you turn
it too high, to protect both transformers. It was part of the process
to qualify a new transformer for our products. It also helped catch a
bad vendor who changed the design, do save them a little money after the
design was accepted.


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There are two kinds of people on this earth:
The crazy, and the insane.
The first sign of insanity is denying that you're crazy.

"Michael A. Terrell" wrote in message
m...

"Dave Plowman (News)" wrote:

In article ,
Ardent wrote:
Someone plugged my Dream machine (rated 110 VAC) into a 220 VAC outlet
and the transformer primary got trashed. Since I will be living here
for a while I thought of getting a transformer made here locally (very
cheap, honest).

I'm willing to bet it's rather more than just the transformer. Copper
takes time to melt while solid state destructs near instantly.


You are ignoring core saturation. That limits the maximum voltage on
the secondary. I have replaced several 120 VAC transformers that opened
when plugged into 240 VAC and had no problems with the electronics. You
aren't always lucky, but if it is a typical cheap as possible
transformer it will die first.



I reckon you've been lucky then Michael. Living here in a 240v country, I
see several pieces of kit a year that have either come over from the states
with their owners to live here, or have been brought back here by UK holiday
makers, picking up that 'deal of the century' at Walmart. Almost always,
although agreed not *always* always, in my experience, the damage which
ensues from plugging these 120v transformer based items into 240v line
power, is not limited to just the transformer primary winding failing.

However, I have seen more than a few which have had a perfectly conventional
glass fuse in the primary, which has failed violently, but has managed to
protect both the transformer, and the following circuitry ...

Arfa

On Wed, 10 Sep 2008 06:22:48 +0530, Ardent
wrote:

Hi Friends

Someone plugged my Dream machine (rated 110 VAC) into a 220 VAC outlet
and the transformer primary got trashed. Since I will be living here
for a while I thought of getting a transformer made here locally (very
cheap, honest).

There are two independent secondaries and will thank anyone who can
tell me what the outputs are.

You may be have to figure out the voltages by looking at the circuit
that are being powered. Power supply cap voltages will give you a
maximum, and IC data sheets should also help. Have you done an
autopsy on the old transformer? Sometimes the primary opens like a
fuse near one end where it's soldered to the wires.

It's unlikely that Sony will sell parts, or even a service manual for
something as inexpensive as a clock radio. I also doubt you will be
able to buy a replacement transformer for less than the cost of a new
radio. It's fine if you want to do this for the challenge, but it
won't be a money saving venture.
Andy Cuffe

Arfa Daily wrote:

"Michael A. Terrell" wrote in message
m...

"Dave Plowman (News)" wrote:

In article ,
Ardent wrote:
Someone plugged my Dream machine (rated 110 VAC) into a 220 VAC outlet
and the transformer primary got trashed. Since I will be living here
for a while I thought of getting a transformer made here locally (very
cheap, honest).

I'm willing to bet it's rather more than just the transformer. Copper
takes time to melt while solid state destructs near instantly.


You are ignoring core saturation. That limits the maximum voltage on
the secondary. I have replaced several 120 VAC transformers that opened
when plugged into 240 VAC and had no problems with the electronics. You
aren't always lucky, but if it is a typical cheap as possible
transformer it will die first.



I reckon you've been lucky then Michael. Living here in a 240v country, I
see several pieces of kit a year that have either come over from the states
with their owners to live here, or have been brought back here by UK holiday
makers, picking up that 'deal of the century' at Walmart. Almost always,
although agreed not *always* always, in my experience, the damage which
ensues from plugging these 120v transformer based items into 240v line
power, is not limited to just the transformer primary winding failing.

However, I have seen more than a few which have had a perfectly conventional
glass fuse in the primary, which has failed violently, but has managed to
protect both the transformer, and the following circuitry ...


You also have the problem of 50 Hz, vs 60 Hz, which requires a larger
core, and makes it easier to saturate a transformer made for the North
America markets. If the primary is impedance limited, it allows the core
to heat quite a bit before the primary winding opens. If the DC supply
is close to the upper limit on the semiconductors, or electrolytics, it
does a lot of damage before it opens. That was why we tested a lot of
parameters on iron core transformers.

It was even worse when we moved to SMPS. We went through a dozen
suppliers before we found one that met our EMI requirements. the rest
either radiated too much noise, or had noise on the DC rails, and it was
within one of the IF frequencies. All SMPS had to be tested for over
current shutdown, and even then we had one fail in a radio during burn
in. It didn't shut down, and it destroyed a new $20,000 radio a customer
was waiting for.


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There are two kinds of people on this earth:
The crazy, and the insane.
The first sign of insanity is denying that you're crazy.

"Ardent" wrote in message
...
Hi Friends

Someone plugged my Dream machine (rated 110 VAC) into a 220 VAC outlet
and the transformer primary got trashed. Since I will be living here
for a while I thought of getting a transformer made here locally (very
cheap, honest).

There are two independent secondaries and will thank anyone who can
tell me what the outputs are.

--
Thanks for your time and attention

Ardent

Someone? Would that someone happen to be you? Because if it wasn't I
wouldn't worry about getting a new transformer I would just beat down the
person that did it and make them eat the Dream Machine.

It's unlikely that Sony will sell parts, or even a service
manual for something as inexpensive as a clock radio.

Of course they will. But this radio is old enough (I assume) that Sony no
longer stocks parts for it. The manual is probably still available, but it's
likely you'll pay a lot for a photocopy.

Businesses (in general) seem to be increasingly less worried about breaking
the laws that require them to stock service parts.

Andy Cuffe wrote:

It's unlikely that Sony will sell parts, or even a service manual for
something as inexpensive as a clock radio.

The service manual is online at www.nodevice.com for 6 Euro's ...

--
Adrian C

In article ,
William Sommerwerck wrote:
It's unlikely that Sony will sell parts, or even a service
manual for something as inexpensive as a clock radio.

Of course they will. But this radio is old enough (I assume) that Sony
no longer stocks parts for it. The manual is probably still available,
but it's likely you'll pay a lot for a photocopy.

Businesses (in general) seem to be increasingly less worried about
breaking the laws that require them to stock service parts.

In the UK it's common to get long warranties on quite low price things - a
3 year one on a 20 quid cordless drill. But they don't repair them if they
go wrong - just give you a like for like replacement or your money back.
Perhaps that's why such things cost about twice as much as in the US. ;-)

--
*I must always remember that I'm unique, just like everyone else. *

Dave Plowman London SW
To e-mail, change noise into sound.

In the UK it's common to get long warranties on quite low price things --
a 3 year one on a 20 quid cordless drill. But they don't repair them if
they
go wrong - just give you a like for like replacement or your money back.
Perhaps that's why such things cost about twice as much as in the US.

It's usually the other 'way round -- products cost less (for whatever
reasons) in the States. I bought a nice name-brand 12V cordless drill for
$20 at Home Despot last Christmas. Hardly pro quality, but fine for light
home work.

"William Sommerwerck" wrote in message
. ..
In the UK it's common to get long warranties on quite low price things --
a 3 year one on a 20 quid cordless drill. But they don't repair them if
they
go wrong - just give you a like for like replacement or your money back.
Perhaps that's why such things cost about twice as much as in the US.

It's usually the other 'way round -- products cost less (for whatever
reasons) in the States. I bought a nice name-brand 12V cordless drill for
$20 at Home Despot last Christmas. Hardly pro quality, but fine for light
home work.



Er, that's what he said William ... " ... cost about twice as much as
in the US" :-)

Arfa