[Iain Churches]

Greetings RATs.

My neighbour invited me to listen to his new sound system this evening
Quite pleasing, except that it was plagued by loud mains-borne clicks,
which came from the fridge everytime the compressor stopped.

How can these clicks be suppressed?

Iain

[tubegarden]

Iain Churches wrote:
Greetings RATs.

My neighbour invited me to listen to his new sound system this evening
Quite pleasing, except that it was plagued by loud mains-borne clicks,
which came from the fridge everytime the compressor stopped.

How can these clicks be suppressed?

Iain

Hi RATs!

If the wiring is three wire, hot, neutral and ground, and both outlets,
for the fridge and the boom box are wired correctly, there is something
wrong with the fridge or the boom box, or both.

If two wire or other vaugaries, play with polarity or just unplug the
fridge while listening.

Happy Ears!
Al

[PhattyMo]

Iain Churches wrote:
Greetings RATs.

My neighbour invited me to listen to his new sound system this evening
Quite pleasing, except that it was plagued by loud mains-borne clicks,
which came from the fridge everytime the compressor stopped.

How can these clicks be suppressed?

Iain



I've got a flourescent light in a closet apparently on the same circuit
as my stereo..Every time someone turns it on or off I get a loud click.

So far,nothing I've tried has cured it..surge strips,noise filters,etc.
I even tried putting an R/C snubber across the switch. No luck.

I'm thinking of just replacing the fixture with an incandescent or
something.
Any other suggestions to eliminate it?

[Trevor Wilson]

"Iain Churches" wrote in message
. ..
Greetings RATs.

My neighbour invited me to listen to his new sound system this evening
Quite pleasing, except that it was plagued by loud mains-borne clicks,
which came from the fridge everytime the compressor stopped.

How can these clicks be suppressed?

**Several possibilities:
* Employ suppression components AT THE COMPRESSOR SWITCH. You need to stop
the crap from entering the wiring.
* Run a separate spar for the hi fi power (All serious audiophiles would be
well advised to do this anyway).

BTW: Don't bother trying to suppress the clicks at the hi fi. Won't work.


--
Trevor Wilson
www.rageaudio.com.au



--
Posted via a free Usenet account from http://www.teranews.com

[Eeyore]

PhattyMo wrote:

Iain Churches wrote:
Greetings RATs.

My neighbour invited me to listen to his new sound system this evening
Quite pleasing, except that it was plagued by loud mains-borne clicks,
which came from the fridge everytime the compressor stopped.

How can these clicks be suppressed?

I've got a flourescent light in a closet apparently on the same circuit
as my stereo..Every time someone turns it on or off I get a loud click.

So far,nothing I've tried has cured it..surge strips,noise filters,etc.
I even tried putting an R/C snubber across the switch. No luck.

I'm thinking of just replacing the fixture with an incandescent or
something.
Any other suggestions to eliminate it?

Use a CFL.

Graham

[Ian Iveson]

Iain Churches wrote

My neighbour invited me to listen to his new sound system this
evening
Quite pleasing, except that it was plagued by loud mains-borne
clicks,
which came from the fridge everytime the compressor stopped.

How can these clicks be suppressed?

My mains-powered supercheap computer speakers and 35yr old fridge
behave in just the same way. I assume they are both at fault. Other
sound systems I have don't respond to the fridge, and the speakers are
oblivious to everything else in the house. Considering they are
rubbish even when not conspiring with the fridge, I don't care enough
to investigate beyond ensuring it's not coming from the computer's
audio output. The clicks are louder than the audio, so I guess there
must be heaps of gain somewhere, and the clicks are modulated high
frequency that enters the open loop and is not dealt with by the
feedback.

Is it characteristic of fridge thermostats to be nervous and
indecisive, or is it a senility thing? I guess new fridges must have
this sorted to meet regulations. What bothers me more is the physical
shaking and buzzing. Maybe they are related? Not much DIY you can do
on a fridge. Perhaps there is a failing cap in there somewhere? Hmm,
just found a bottle of fungicide stuck down the radiator...

If my main sound system was bothered by the fridge I would be *very*
disappointed. Had I bought it new, I would probably return it. Aren't
new things supposed to be immune?

How do you know it's mains-borne, BTW?

In sympathy, Ian

[Iain Churches]

"tubegarden" wrote in message
ps.com...

Iain Churches wrote:
Greetings RATs.

My neighbour invited me to listen to his new sound system this evening
Quite pleasing, except that it was plagued by loud mains-borne clicks,
which came from the fridge everytime the compressor stopped.

How can these clicks be suppressed?

Iain

Hi RATs!

If the wiring is three wire, hot, neutral and ground, and both outlets,
for the fridge and the boom box are wired correctly, there is something
wrong with the fridge or the boom box, or both.

If two wire or other vaugaries, play with polarity or just unplug the
fridge while listening.

Happy Ears!
Al


Hi Al,

Both fridge and audio system are three wire, moulded IEC cables,
but from the same spur. Here in Scandinavia, the mains plug can be
inserted either way round. I will experiment with the polarity as
you suggest.

Hope you thrive.
Iain

[Iain Churches]

"Trevor Wilson" wrote in message
.. .

"Iain Churches" wrote in message
. ..
Greetings RATs.

My neighbour invited me to listen to his new sound system this evening
Quite pleasing, except that it was plagued by loud mains-borne clicks,
which came from the fridge everytime the compressor stopped.

How can these clicks be suppressed?

**Several possibilities:
* Employ suppression components AT THE COMPRESSOR SWITCH. You need to stop
the crap from entering the wiring.

Hi Trevor.

Can you please explain the above in a bit more detail.

TIA
Iain

[Iain Churches]

"Ian Iveson" wrote in message
. uk...

The clicks are louder than the audio, so I guess there must be heaps of
gain somewhere, and the clicks are modulated high frequency that enters the
open loop and is not dealt with by the feedback.

Yes, the same in this case, they are horrendously loud, and correspond
exactly with the moment the compressor shuts off.

If my main sound system was bothered by the fridge I would be *very*
disappointed. Had I bought it new, I would probably return it. Aren't new
things supposed to be immune?

One would have thought so:-) He keeps the fridge in the music room so
that he can offer a glass of chilled wine during a listening session and
after
sauna. So hopefully, the fridge can be tamed so that it can stay in the
same
place

How do you know it's mains-borne, BTW?

Well, as the only connection the two have in common is the mains ring,
I made an assumption.....

Cheers
Iain

[Peter Wieck]

Iain Churches wrote:
Greetings RATs.

My neighbour invited me to listen to his new sound system this evening
Quite pleasing, except that it was plagued by loud mains-borne clicks,
which came from the fridge everytime the compressor stopped.

How can these clicks be suppressed?

Iain

After reading the entire thread, I finally got enough information to
understand the problem. The moment you revealed that the fridge was in
the same room as the system, even more became clear.

Put simply, either the fridge is cheaply (poorly) made and/or the
start-capacitor on the compressor motor is shot (or even never was if
this is one of those tiny little Chinese or Turkish models). This would
drop a massive transient back into the line the moment the motor shuts
down. That transient could easily be strong enough to back through the
Panel, even were the system on a separate line. Given that the fridge
is probably a sealed unit, it is not very hopeful that you will be able
to cure this.

Lose the fridge.

There is some remote hope were you to install a true line-conditioner
(this is NOT a UPS, nor is it a surge-surpressor, although it will
perform the second function as well).

http://www.tripplite.com/products/co...ners/index.cfm

http://www.pricegrabber.com/search_a...hp/page_id=56/

And so forth.

Lose the fridge. There are easier ways to keep wine cool than a
compressor-driven fridge.

http://www.savinglots.com/lotprod.asp?item=EC15W-2

Is one of them. There are many others.

Peter Wieck
Wyncote, PA

[Peter Wieck]

PhattyMo wrote:

I've got a flourescent light in a closet apparently on the same circuit
as my stereo..Every time someone turns it on or off I get a loud click.

So far,nothing I've tried has cured it..surge strips,noise filters,etc.
I even tried putting an R/C snubber across the switch. No luck.

Replace the ballast with an electronic ballast vs. a starter (shorting)
type. That will cure it.

It _will_ be cheaper to replace the entire fixture as you suggest, BTW.
Then you may install a PL-type lamp, or an incandescent if the PL
continues the problem. Good ones do not.

Peter Wieck
Wyncote, PA

[Ian Iveson]

Peter wrote

...This would drop a massive transient back into the line...

Aaargh.

As a noun, "transient" sounds like a word used by politicians to
dehumanise victims. It has no place in electronics.

In electronics, "transient" is best kept as an adjective, as in
"transient response".

Perhaps we have tangled over this before? Was it you that said the
ideal transient response is 1? Eek.

Another fundamental misunderstanding of control system theory. Please
give it some thought.

cheers, Ian

[Peter Wieck]

Ian Iveson wrote:
Peter wrote

...This would drop a massive transient back into the line...

Aaargh.

Perhaps we have tangled over this before? Was it you that said the
ideal transient response is 1? Eek.

No, not hardly.


Main Entry: 2transient
Function: noun
1 : one that is transient: as a : a transient guest b : a person
traveling about usually in search of work
2 a : a temporary oscillation that occurs in a circuit because of a
sudden change of voltage or of load b : a transient current or voltage

However, Webster's would disagree per the above.

http://www.m-w.com/dictionary/transient

Peter Wieck
Wyncote, PA

[tubegarden]

Hi RATs!

Move the wine to the real fridge. The little noisey box in the
listening room was a silly infactuation. He'll get over it.

If he buys some larger wine glasses, he won't have to make as many
trips.

In home audio, bigger is everything

Happy Ears!
Al

[Ian Iveson]

Iain wrote

The clicks are louder than the audio, so I guess there must be heaps
of gain somewhere, and the clicks are modulated high frequency that
enters the open loop and is not dealt with by the feedback.

Yes, the same in this case, they are horrendously loud, and
correspond
exactly with the moment the compressor shuts off.

Observing mine more diligently, I find there is a single soft click
when the compressor switches on, and a loud, long, random train of
pulses when it switches off. The compressor itself doesn't stutter,
but comes to a juddering halt only when the clicks stop. Perhaps
arcing across the thermostat contacts as they open produces enough
heat to close them again a few times. Worn contacts tend to arc more,
so it must make itself worse over time.

So, if we can suppress the arcing, we can obviate the need for
filtering after the event. It's a low resistance, high current circuit
with a lot of inductance. Varistor, maybe, or a heavy-duty cap with
small series resistance, across the contacts?


If my main sound system was bothered by the fridge I would be
*very* disappointed. Had I bought it new, I would probably return
it. Aren't new things supposed to be immune?

One would have thought so:-) He keeps the fridge in the music room
so
that he can offer a glass of chilled wine during a listening session
and after
sauna. So hopefully, the fridge can be tamed so that it can stay in
the same
place

A fridge is not euphonic and neither is the sound of ppl using it.
Your neighbour should remove it from the listening room, and bring
drinks on a tray. Self-service hospitality is a contradiction in
terms.

How do you know it's mains-borne, BTW?

Well, as the only connection the two have in common is the mains
ring,
I made an assumption.....

I know sod all about transistors and the circuits they inhabit, so to
my mind it remains a possibility that the clicks are transmitted
through the air.

regards, Ian

[Ian Iveson]

Peter wrote


...This would drop a massive transient back into the line...

Aaargh.

Perhaps we have tangled over this before? Was it you that said the
ideal transient response is 1? Eek.

No, not hardly.


Main Entry: 2transient
Function: noun
1 : one that is transient: as a : a transient guest b : a person
traveling about usually in search of work
2 a : a temporary oscillation that occurs in a circuit because of a
sudden change of voltage or of load b : a transient current or
voltage

However, Webster's would disagree per the above.

http://www.m-w.com/dictionary/transient


Hmmph.

The problem I have with this usage is that ppl are inclined to think
that the transient response of a system is the system's response to a
transient. This common misunderstanding is a serious block to
progress!

Just to make it clear, the transient response of a system is that part
of the system's response that falls to zero after some time. It is a
property of the system, not of the input. The ideal transient response
of an audio system is zero.

I must admit that, if a usage is common, then it is undeniably part of
the language. That doesn't make it any less confusing. In your sense
of the word, all music signals, and probably all real signals, are
transients. If all signals are transients, then transient has no clear
meaning. How long is a piece of string?

Plenty ppl talk of RMS power. I have to admit the term has currency,
but it doesn't stop me wincing every time I hear it.

"Ongoing", whilst I'm at it, is an abomination. Confusing "current"
with "continuing" allows polititians to say "we have an ongoing
commitment", and mean absolutely nothing.

And "jeep" is not an acronym.

cheers, Ian

[John Byrns]

In article ,
"Ian Iveson" wrote:

Peter wrote

...This would drop a massive transient back into the line...

Aaargh.

As a noun, "transient" sounds like a word used by politicians to
dehumanise victims. It has no place in electronics.

In electronics, "transient" is best kept as an adjective, as in
"transient response".

Ian, I have always suspected that you were the biggest Fruitcake in this
group, now I know it.

If we are to be no longer allowed to use the word "transient" as a noun,
as is common practice in electronics and various other technical fields,
what do you suggest as a replacement for the use of "transient" as a
noun?


Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/

[Jon Yaeger]

My understanding of these things is limited, but nonetheless . . .

Sometimes compressor relays chatter which creates a lot of fast rise-time
noise. Anything that can be done to reduce the chattering of a contactor
relay might help -- they typically run on 24 VAC.

When I was building PCs and had to get FCC approval, I had to add a noise
filter to the A/C side of the switching power supply to prevent artifacts
from going back into the mains.

I wonder if a standard computer type mains noise filter could be added to
the refrigerator. It would have to take into account the LRA (locked rotor
amperage) of the compressor, which is fairly high for single phase circuits.

In the US a house typically has two 120 volt "sides" to the box. I don't
know what the OP has but maybe it would help to move the hifi or the
refrigerator to the other "side" of the mains box.

Jon

[Ian Iveson]

John Byrns wrote


...This would drop a massive transient back into the line...

Aaargh.

As a noun, "transient" sounds like a word used by politicians to
dehumanise victims. It has no place in electronics.

In electronics, "transient" is best kept as an adjective, as in
"transient response".

Ian, I have always suspected that you were the biggest Fruitcake in
this
group, now I know it.

If we are to be no longer allowed to use the word "transient" as a
noun,
as is common practice in electronics and various other technical
fields,
what do you suggest as a replacement for the use of "transient" as a
noun?

Pulse?

I'm a prophet not a dictionary.

Something with some descriptive value would help.

But you are "allowed" to continue as you wish, as far as I care.

Sweetness and light, Ian

[John Byrns]

In article ,
"Ian Iveson" wrote:

Peter wrote


...This would drop a massive transient back into the line...

Aaargh.

Perhaps we have tangled over this before? Was it you that said the
ideal transient response is 1? Eek.

No, not hardly.


Main Entry: 2transient
Function: noun
1 : one that is transient: as a : a transient guest b : a person
traveling about usually in search of work
2 a : a temporary oscillation that occurs in a circuit because of a
sudden change of voltage or of load b : a transient current or
voltage

However, Webster's would disagree per the above.

http://www.m-w.com/dictionary/transient


Hmmph.

The problem I have with this usage is that ppl are inclined to think
that the transient response of a system is the system's response to a
transient. This common misunderstanding is a serious block to
progress!

What is "the transient response of a system", can you define it? Are
you sure you don't mean the "impulse response" of a system, which is
well defined.

Just to make it clear, the transient response of a system is that part
of the system's response that falls to zero after some time. It is a
property of the system, not of the input. The ideal transient response
of an audio system is zero.

Hmm, this is confusing, what part of a system's response doesn't fall to
zero, unless the system is oscillating I suppose?

I must admit that, if a usage is common, then it is undeniably part of
the language. That doesn't make it any less confusing. In your sense
of the word, all music signals, and probably all real signals, are
transients. If all signals are transients, then transient has no clear
meaning. How long is a piece of string?

Now you seem to have crossed to the other side of the street. This
seems to be a common audiophile problem but you can't have it both ways.


Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/

[tubegarden]

Hi RATs!

"Transient" does have a certain Panache.

When referring to shut off noise from cheap refridgerators, "Bum" noise
might be appropos ...

Happy Ears!
Al

[Ian Iveson]

John Byrns

What is "the transient response of a system", can you define it?

I just have. That's as far as it goes. To quote a pretty standard
definition from "Feedback and Control Systems" (Di Stefano et al,
McGraw-Hill, 1967),

"The transient response is that part of the total response which
approaches zero as time approaches infinity."

Also

"The steady state response is that part of the total response which
does not approach zero as time approaches infinity."

From which you correctly infer that, by superposition, the total
system response must be equal to the sum of the transient and steady
state responses.

Not to be confused with the forced response and the free response,
which also sum to the total response.

Note that, in all these cases, the word preceding "response" is an
adjective qualifying "response".

Are
you sure you don't mean the "impulse response" of a system, which is
well defined.

"Impulse response" is response to an impulse. If the impulse is of
zero duration, then the steady state response of the system must be
zero, and hence only it's transient response remains. Theoretically,
therefore, at the limit, any response to an impulse must be the
transient response. "Impulse response" arises from the need for a
practical, experimental indication of the transient response of a
system. However, it is a fudge, because if the impulse were of truly
zero duration, then the output of the system would not be measurable.
In practice, if the pulse duration is much shorter than the period of
the transient response of the system, then it is a reasonable
approximation.

We use steps (edges) rather than pulses, generally. A "square wave" is
a reasonable approximation if it's period is more than twice as long
as the system's transient response, and it's rise time is *much*
shorter than the period of the transient response, so we see the
transient response isolated behind each edge, superimposed on the
"square wave" output.

However, there is a danger in concentrating on pulses and "square
waves". In response to a sine wave input, a system will equally have a
transient and a steady state response. The steady state response is
copy of the original sine wave, although possibly of different
amplitude and possibly shifted in phase. The transient response, which
fills in the difference between the original and the copy, is a kind
of distortion which dies away, we hope within a cycle or two of the
input signal. With zero transient response, there will be none of this
distortion, because the system will always reach its steady state
response immediately, and if the system is linear all inputs will be
reproduced exactly, in real time, including pulse inputs.

Hence, seemingly paradoxically by your common meaning of "transient",
a linear system with zero transient response will reproduce all
"transients" perfectly.

Now do you see the scope for confusion?

Just to make it clear, the transient response of a system is that
part
of the system's response that falls to zero after some time. It is
a
property of the system, not of the input. The ideal transient
response
of an audio system is zero.

Hmm, this is confusing, what part of a system's response doesn't
fall to
zero, unless the system is oscillating I suppose?

The steady state response. Yes it can become confusing. For a linear
system, oscillation is not a response, because it happens with no
input. See example of sine wave above. If the steady state response is
achieved instantaneously, then response to a changing input is an
instantaneous copy of the input. If the input falls to zero, so will
the output, at the same time.

Last time I went through this, those who insisted on clinging to their
misconceptions were forced to state that the ideal transient response
is unity. That's where their theoretical framework falls apart.

I must admit that, if a usage is common, then it is undeniably part
of
the language. That doesn't make it any less confusing. In your
sense
of the word, all music signals, and probably all real signals, are
transients. If all signals are transients, then transient has no
clear
meaning. How long is a piece of string?

Now you seem to have crossed to the other side of the street. This
seems to be a common audiophile problem but you can't have it both
ways.

Why not? Feedback is another word with a loose, common meaning, and a
tight, engineering sense. RMS is similarly confused. I am trying to
point out, as simply as I can, how using these terms willy-nilly can
lead to misconceptions. I can acknowledge loose definitions and also
warn against the confusion they bring, surely?

It's not the language that bothers me. If language doesn't change
then, like everything else, it dies. The direction of change towards
sloppiness does bother me, because it's another way of dying...via
hegemony, I fear, in which language becomes superfluous to some
universal, common sense which by its homogeneity obviates any need for
expression. It's the wrong way back to the garden.

cheers, Ian

[Trevor Wilson]

"Iain Churches" wrote in message
. ..

"Trevor Wilson" wrote in message
.. .

"Iain Churches" wrote in message
. ..
Greetings RATs.

My neighbour invited me to listen to his new sound system this evening
Quite pleasing, except that it was plagued by loud mains-borne clicks,
which came from the fridge everytime the compressor stopped.

How can these clicks be suppressed?

**Several possibilities:
* Employ suppression components AT THE COMPRESSOR SWITCH. You need to
stop the crap from entering the wiring.

Hi Trevor.

Can you please explain the above in a bit more detail.

**Two methods, I can think of:

* Get real sophisticated and substitute a TRIAC control for the motor,
rather than mechanical switches. A TRIAC can be arranged to switch at the
zero crossing point of the mains waveform and thus deliver no interference.
Mechanical switches cannot.
* Put a 'snubber' across the motor switch contacts. Usually, this will
consist of an appropriately rated capacitor and series resistor.


--
Trevor Wilson
www.rageaudio.com.au



--
Posted via a free Usenet account from http://www.teranews.com

[Name]

Very nice. Thank you for the much-needed summary.

I would ask you, though, not to spell "its" with an apostrophe.

-Henry

[Iain Churches]

"Trevor Wilson" wrote in message
.. .

"Iain Churches" wrote in message
. ..

"Trevor Wilson" wrote in message
.. .

"Iain Churches" wrote in message
. ..
Greetings RATs.

My neighbour invited me to listen to his new sound system this evening
Quite pleasing, except that it was plagued by loud mains-borne clicks,
which came from the fridge everytime the compressor stopped.

How can these clicks be suppressed?

**Several possibilities:
* Employ suppression components AT THE COMPRESSOR SWITCH. You need to
stop the crap from entering the wiring.

Hi Trevor.

Can you please explain the above in a bit more detail.

**Two methods, I can think of:

* Get real sophisticated and substitute a TRIAC control for the motor,
rather than mechanical switches. A TRIAC can be arranged to switch at the
zero crossing point of the mains waveform and thus deliver no
interference. Mechanical switches cannot.
* Put a 'snubber' across the motor switch contacts. Usually, this will
consist of an appropriately rated capacitor and series resistor.


Thanks Trevor. I will pass the word on.

Iain

[Ian Iveson]

Very nice. Thank you for the much-needed summary.

I would ask you, though, not to spell "its" with an apostrophe.

Sorry. I usually get it right, I hope.

Embarrassed, Ian

[@(none)]

Iain Churches wrote:
Greetings RATs.

My neighbour invited me to listen to his new sound system this evening
Quite pleasing, except that it was plagued by loud mains-borne clicks,
which came from the fridge everytime the compressor stopped.

How can these clicks be suppressed?

Iain

When I was designing audio-apparatus for a manufacturer, I once had
a mixing-console allmost finished. When it was demonstrated to the
companies salesmen, the first thing one of them did was switching
off and on the light in the office... click - click.

I was told to redesign it to be immune for clicks.
Here is Europe there are regulations for electric and electronic
apparatus to be immune for interference from other apparatus and
not to generate such.
In the real world such interferences can be expected everywhere,
not just a fridge.

So, the neighbour should take his soundsystem back to the dealer
and ask him to find a solution.

BTW.
In the mixing-console, the cause for the sensitivity to clicks was
the use of a single transistor, prior to the first op-amp ( for low-
noise ) in the phono-input stages. The transistor was biased with
a few Volt so it could get its emitter-current from the feedback
loop. Replacing this by a two-transistor differential in a well-
known configuration solved the problem completely.

Meantime, what kind of soundsystem are we talking about ?
Tubes of-cause!
power-amp - pre-amp - CD - phono - tuner ?
-- Wooden cabinet for the amplifier ???? ( come all in you clicks )
When you disconnect all signal sources from the amplifier, does it
still click ?

Andre

[Eeyore]

none wrote:

Iain Churches wrote:
Greetings RATs.

My neighbour invited me to listen to his new sound system this evening
Quite pleasing, except that it was plagued by loud mains-borne clicks,
which came from the fridge everytime the compressor stopped.

How can these clicks be suppressed?

Iain

When I was designing audio-apparatus for a manufacturer, I once had
a mixing-console allmost finished. When it was demonstrated to the
companies salesmen, the first thing one of them did was switching
off and on the light in the office... click - click.

May I enquire which company that was ?


Graham

[Peter Wieck]

Ian Iveson wrote:

And "jeep" is not an acronym.

No. "Jeep" is not an acronym.

GP is. (General Purpose [vehicle]).

Peter Wieck
Wyncote, PA

[Peter Wieck]

Ian Iveson wrote:

The problem I have with this usage is that ppl are inclined to think
that the transient response of a system is the system's response to a
transient. This common misunderstanding is a serious block to
progress!

Ian:

There are always terms-of-art embedded in every discipline or
belief-system, many of which are contrary to both common usage and
common sense. It is incumbent on any writer (not "upon" as we are being
persnickety) to clarify or define such terms if context is not
sufficient. It is also necessary for any writer to choose words from
most-to-least common usage. I will quite often use the term 'peculiar',
but not as how I would describe a two-headed chicken or Commander
Middius, but in the sense of specific or 'singular to'. In this
typically non-literary venue, it is important that I clarify such
usage... unless I am describing said chicken or commander. Similarly
with 'accuracy' or 'precision' in their various forms. This last as it
seems that tech-types are most likely to confuse the two in my
experience.

The brute fact of the matter is that English is an incredibly rich
language such that there is really no need to use the second cousin of
the word one really wants, there is in nearly every case one that means
exactly what is wanted. And at the same time, it is impossible to
protect from ignorance. If readers fail to understand a properly
written piece, it is not necessarily the fault of the writer. However,
if the writer leaves a single 'edgewise' for misunderstanding, it will
happen.

Pick a word, any word. Put it in many contexts and see how it serves
many masters. How many uses are you able to pick for "umbrella"? Do
they work for "parasol"? "bumbershoot"?

Not hardly.

Do each of those two have their own peculiar multiple contexts?

You bet.

So, if one wishes to eliminate the potential for misunderstanding...
pick the right word. If one is trying to communicate a specific concept
in an established context, use the most common-usage word possible as
there is no possible potential for misunderstanding -WITHIN - the
established context.

Technical writers are notorious for not understanding the need for
simplicity when writing directions for example, and the need to avoid
terms-of-art that are also not absolutely clear from both context and
common usage.

Peter Wieck
Wyncote, PA

[Sander deWaal]

"Iain Churches" said:


One would have thought so:-) He keeps the fridge in the music room so
that he can offer a glass of chilled wine during a listening session and
after
sauna. So hopefully, the fridge can be tamed so that it can stay in the
same
place


Bad idea.
The buzzing of the compressor would drive me nuts.
I suffer from this problem already, while the fridge (A Bosch, you
will note) is in the kitchen and my listening room is 15 meters away,
it interferes with my listening already (low frequency artefacts).

Even if you'd solve the clicks and pops, the buzzing and humming would
still be there.

--
"Due knot trussed yore spell chequer two fined awl miss steaks."

[RickH]

First try to run a long extension cord from an outlet in another room
that you know is on a completely different branch circuit than the
fridge, also an outlet preferably on the "other side" of the phase,
then use that cord to power the stereo. If the spike goes away then
just pull a new dedicated branch outlet to the listening room on its
own breaker (assuming you have conduit this should not be too hard).
Chances are that the fridge spike is not large enough to make it all
the way back to the mains panel then back out again on another branch,
especially if the other branch is also on the other side of the split
phase of your street transformer. In general dont run electronics on
the same branch circuit as motors. Filters might work but just as
often dont work. I install intercoms, lighting control, security
systems, etc. as a side job and have same issues with powerline control
devices like X10 which are just putting transients on the line
deliberately to pass data for control purposes on the powerline.
Sometimes plugging a UPS supply for your computer into the same circuit
as the motor will also absorb the spikes, UPS systems have the added
"benefit" of absorbing transents on the line that they are plugged
into. When debugging an X10 or other PLC carrier house, often a UPS
will absorb your desired control signals when you dont want them too.
Thats why the industry is going to hybrid RF/PLC repeating mesh
networks like SmartHome Insteon, very dependable.



Iain Churches wrote:
Greetings RATs.

My neighbour invited me to listen to his new sound system this evening
Quite pleasing, except that it was plagued by loud mains-borne clicks,
which came from the fridge everytime the compressor stopped.

How can these clicks be suppressed?

Iain

[Iain Churches]

Hi Rick. You top posted so I will top post my reply.
Thanks for the tip. This evening we tried an extension cord
coming from another part of the house and the click has
disappeared.

Your help much appreciated
Iain



"RickH" wrote in message
ups.com...
First try to run a long extension cord from an outlet in another room
that you know is on a completely different branch circuit than the
fridge, also an outlet preferably on the "other side" of the phase,
then use that cord to power the stereo. If the spike goes away then
just pull a new dedicated branch outlet to the listening room on its
own breaker (assuming you have conduit this should not be too hard).
Chances are that the fridge spike is not large enough to make it all
the way back to the mains panel then back out again on another branch,
especially if the other branch is also on the other side of the split
phase of your street transformer. In general dont run electronics on
the same branch circuit as motors. Filters might work but just as
often dont work. I install intercoms, lighting control, security
systems, etc. as a side job and have same issues with powerline control
devices like X10 which are just putting transients on the line
deliberately to pass data for control purposes on the powerline.
Sometimes plugging a UPS supply for your computer into the same circuit
as the motor will also absorb the spikes, UPS systems have the added
"benefit" of absorbing transents on the line that they are plugged
into. When debugging an X10 or other PLC carrier house, often a UPS
will absorb your desired control signals when you dont want them too.
Thats why the industry is going to hybrid RF/PLC repeating mesh
networks like SmartHome Insteon, very dependable.



Iain Churches wrote:
Greetings RATs.

My neighbour invited me to listen to his new sound system this evening
Quite pleasing, except that it was plagued by loud mains-borne clicks,
which came from the fridge everytime the compressor stopped.

How can these clicks be suppressed?

Iain

[Iain Churches]

"Sander deWaal" wrote in message
...
"Iain Churches" said:


One would have thought so:-) He keeps the fridge in the music room so
that he can offer a glass of chilled wine during a listening session and
after
sauna. So hopefully, the fridge can be tamed so that it can stay in the
same
place


Bad idea.
The buzzing of the compressor would drive me nuts.
I suffer from this problem already, while the fridge (A Bosch, you
will note) is in the kitchen and my listening room is 15 meters away,
it interferes with my listening already (low frequency artefacts).

Even if you'd solve the clicks and pops, the buzzing and humming would
still be there.

¨

Hi Sander.

The fridge itself is almost silent when running. This one too is a Bosch,
one of those bright blue "1950's retro" fridges. It is huge and fits
perfectly
into the alcove where it now resides, so moving it to another place is not
really practical. We have now tried running the fridge from a long
extension cord from another part of the house. This seems to have cured
the problem.

Iain

[@(none)]

Eeyore wrote:

none wrote:


Iain Churches wrote:

Greetings RATs.

My neighbour invited me to listen to his new sound system this evening
Quite pleasing, except that it was plagued by loud mains-borne clicks,
which came from the fridge everytime the compressor stopped.

How can these clicks be suppressed?

Iain

When I was designing audio-apparatus for a manufacturer, I once had
a mixing-console allmost finished. When it was demonstrated to the
companies salesmen, the first thing one of them did was switching
off and on the light in the office... click - click.


May I enquire which company that was ?


Graham


May I enquire if the amplifier in question was "homebrew" by yourselve ?

Andre

[Bob H.]

It sounds like that ac branch is unable to supply enough current to
satisfy the start cap. Try another circuit on a different breaker.

Also, the ac earth grounding may not be sufficient, or have corrosion,
and the click may be riding on the ground circuit between the power
panel and the outlet. Check/clean the grounding connections at the
plug. Some breaker panels have the copper grounding wires running to a
bar with screws which tighten onto the wire. Try tightening these
screws for better grounding, and possibly sanding the ground wire going
to the applicable outlet. Check the main earth ground connection for
corrosion.

Try pulling the breaker and sanding the breaker contacts for any
corrosion (don't touch the breaker panel rails!!)
Also, the breaker itself may be internally corroded. Try another
breaker (which can be returned if necessary).

Last, an isolation transformer in addition to a conditioner may do the
trick at the stereo, a fully regulating UPS, or a solid state
regulating conditioner (using SCR's) should also work.
Cheaper passive conditioners usually don't do much of anything, except
possibly damping large spikes for protection from storms, etc. For the
money needed for fancy conditioners, you might as well get an actively
regulating conditioner.

UPS's which only switch in the battery in case of power failure will
probably be useless for this problem, since it's only a passive
conditioner most of the time.

Please use extreme caution if working around outlets or in a power
panel. If you have any reservations at all about it, don't do it.
Period.

Hope this helps
Bob H.




Greetings RATs.

My neighbour invited me to listen to his new sound system this evening
Quite pleasing, except that it was plagued by loud mains-borne clicks,
which came from the fridge everytime the compressor stopped.

How can these clicks be suppressed?

Iain

[Eeyore]

"Bob H." wrote:

It sounds like that ac branch is unable to supply enough current to
satisfy the start cap.

Rubbish.

It the thermostat contacts arcing. They should be suppressed. A very common
problem with older fridges.

Graham

[Iain Churches]

"Eeyore" wrote in message
...


"Bob H." wrote:

It sounds like that ac branch is unable to supply enough current to
satisfy the start cap.

Rubbish.

The music room is fed from its own 16A spur.

It the thermostat contacts arcing. They should be suppressed. A very
common
problem with older fridges.


Graham


The fridge is a new one, top of the range Bosch,
Powering it from a cable from a different room (spur) seems to have solved
the
problem.

Iain

[Iain Churches]

"Bob H." wrote in message
ups.com...
It sounds like that ac branch is unable to supply enough current to
satisfy the start cap. Try another circuit on a different breaker.

The fridge and the audio system share the same 16A spur. There is
nothing else powered from this branch. The amp has a 2A fuse. What
kind of power does a fridge consume. Not much, I guess.


Also, the ac earth grounding may not be sufficient, or have corrosion,
and the click may be riding on the ground circuit between the power
panel and the outlet. Check/clean the grounding connections at the
plug. Some breaker panels have the copper grounding wires running to a
bar with screws which tighten onto the wire. Try tightening these
screws for better grounding, and possibly sanding the ground wire going
to the applicable outlet. Check the main earth ground connection for
corrosion.

Try pulling the breaker and sanding the breaker contacts for any
corrosion (don't touch the breaker panel rails!!)
Also, the breaker itself may be internally corroded. Try another
breaker (which can be returned if necessary).

Last, an isolation transformer in addition to a conditioner may do the
trick at the stereo, a fully regulating UPS, or a solid state
regulating conditioner (using SCR's) should also work.
Cheaper passive conditioners usually don't do much of anything, except
possibly damping large spikes for protection from storms, etc. For the
money needed for fancy conditioners, you might as well get an actively
regulating conditioner.

UPS's which only switch in the battery in case of power failure will
probably be useless for this problem, since it's only a passive
conditioner most of the time.

Please use extreme caution if working around outlets or in a power
panel. If you have any reservations at all about it, don't do it.
Period.

Hope this helps
Bob H.


Bob. Many thanks for your suggestions. A temporary solution
has been found by powering the fridge from a separate spur.
We will try the isolation transformer next.

Iain

[Bob H.]

The fridge and the audio system share the same 16A spur. There is
nothing else powered from this branch. The amp has a 2A fuse. What
kind of power does a fridge consume. Not much, I guess.



The problem is not total current, but a very large spike or spikes
caused when a motor turns on, either from the start cap, or arcing in
contacts. The spike is very large (sometimes thousands of volts), and
has a very short time duration, resulting in a very small average
current, but able to make it's way through most filter networks.

Your fridge probably doesn't take a lot of power, but when the
compressor motor cuts on, it takes a lot of short duration current.

The imagining equipment I work on is suseptable to these spikes, and we
spec the equipment power to be physically seperated from other
equipment, or be isolated by a transformer (which still may not be
enough), or a AC to DC to AC regulator.

I'd recommend a returnable transformer if it doesn't do the job.

Good luck
Bob H.