sci.electronics.repair - 25 new messages in 6 topics - digest

sci.electronics.repair
http://groups.google.com/group/sci.electronics.repair?hl=en

sci.electronics.repair@googlegroups.com

Today's topics:

* Supergluing your fingers together - 2 messages, 2 authors
http://groups.google.com/group/sci.electronics.repair/t/27d3b5cbe57935fb?hl=en
* Why we have Gravity - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/004d04dfe74c9553?hl=en
* Weird stuff -- update -- (was Electronic Kenmore refrigerator not working,
what does this sign mean) - 8 messages, 6 authors
http://groups.google.com/group/sci.electronics.repair/t/90e33648f2879de5?hl=en
* Yet another bulging-capacitors replacement - 3 messages, 2 authors
http://groups.google.com/group/sci.electronics.repair/t/3ec97de65fce9bb3?hl=en
* Plasma TV Foggy area - 10 messages, 4 authors
http://groups.google.com/group/sci.electronics.repair/t/9e5cdc2b5ff03be3?hl=en
* LORAN C - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/73c2d1e0342e191b?hl=en

==============================================================================
TOPIC: Supergluing your fingers together
http://groups.google.com/group/sci.electronics.repair/t/27d3b5cbe57935fb?hl=en
==============================================================================

== 1 of 2 ==
Date: Fri, Sep 3 2010 12:28 am
From: "N_Cook"

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote in message
news:4C80375D.4020906@electrooptical.net...
> AZ Nomad wrote:
> > On Thu, 2 Sep 2010 11:20:39 -0700, Dave Platt <dplatt@radagast.org>
wrote:
> >>> Surprising I've never done it before . Thumb and second finger firmly
glued
> >>> to either side of a connecctor. I tried methylated spirits first but
no
> >>> effect seemingly. Then dilute acetone as nail varnish remover. I was
> >>> concerned about being too long on the skin so some cotton wool balls
of
> >>> acetone around both areas and a Q-tip soaked in acetone, with a
rotating
> >>> wedge-like motion, cautiously wedging skin from connector worked, but
anyone
> >>> elses experiences/advice for the next time?
> >
> >> Keeping a bottle of superglue debonder around is a cheap investment.
> >> If you go to a hobby store which carries a selection of cyanoacrylate
> >> glues (usually of different viscosities and bonding speeds) you ought
> >> to find a supply of debonder in the same rack.
> >
> >
> > Has anybody ever found an application where superglue works well
> > except on human skin? I find the crap brittle as hell and have yet to
> > see anything glued with it last more than a few weeks before breaking.
>
> I use it on optical things often, because it's easily removed, like Duco
> cement except stronger and faster-setting. As long as you use just a
> little, it doesn't cause too much nasty frosting nearby.
>
> Cheers
>
> Phil Hobbs
>
> --
> Dr Philip C D Hobbs
> Principal
> ElectroOptical Innovations
> 55 Orchard Rd
> Briarcliff Manor NY 10510
> 845-480-2058
> hobbs at electrooptical dot net
> http://electrooptical.net

How do you use "just a little" with the viscosity almost of liquid helium
and coming in aluminium tubes of a gauge almost the same as tin cans it
seems impossible to squeeze out a small drop, only. I must adopt the storage
in small airtight bottle with (non cotton) sachet of activated silica gel
inside. Hopefully then it will be more amenable to squeezing out just enough
to wet a needle point to transfer to the intended.

== 2 of 2 ==
Date: Fri, Sep 3 2010 1:07 am
From: Jeff Liebermann

On Fri, 3 Sep 2010 08:28:29 +0100, "N_Cook" <diverse@tcp.co.uk> wrote:

>I must adopt the storage
>in small airtight bottle with (non cotton) sachet of activated silica gel
>inside. Hopefully then it will be more amenable to squeezing out just enough
>to wet a needle point to transfer to the intended.

There's a trick. I use bottles with a stainless tube for dispensing
cyanoacrylate adhesive. Something like this.
<http://www.technologylk.com/weld-on-applicator-bottle-with-needle-lk-AAB4.htm>
<http://www.hobbylinc.com/htm/mmr/mmrmkdbp.htm>

As soon as you use it, the stainless tip will clog. No problem. Find
a cancer stick igniter, and heat the stainless barrel. There will be
a small puff of noxious smog as the CA burns off, and the tip is
clear.

It's quite easy to dispense just one drop with a stainless tip and
quite difficult with a CA encrusted plastic tip commonly found in the
hardware store CA products. If you want a smaller drop, try a smaller
dispenser barrel.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

==============================================================================
TOPIC: Why we have Gravity
http://groups.google.com/group/sci.electronics.repair/t/004d04dfe74c9553?hl=en
==============================================================================

== 1 of 1 ==
Date: Fri, Sep 3 2010 1:36 am
From: "Michael A. Terrell"

RichTravsky wrote:
>
> "Michael A. Terrell" wrote:
> > RichTravsky wrote:
> > > Bob Villa wrote:
> > > ? On Aug 23, 2:50 pm, "Michael A. Terrell" ?mike.terr...@earthlink.net?
> > > ? wrote:
> > > ? ? Bob Villa wrote:
> > > ? ? ? On Aug 23, 12:24 pm, "Michael A. Terrell" ?mike.terr...@earthlink.net?
> > > ? ? ? wrote:
> > > ? ? ? ? RichTravsky wrote:
> > > ? ? ? ? ? fitz wrote:
> > > ? ?
> > > ? ? ? ? ? ? Why we have Gravity
> > > ? ?
> > > ? ? ? ? ? ? A correct theory of gravity will show us these four (4) things:
> > > ? ? ? ? ? ? 1. It will show us why gravity also acts like acceleration (principle
> > > ? ? ? ? ? ? of equvalence).
> > > ? ? ? ? ? ? 2. It will show us the actual cause of gravity.
> > > ? ? ? ? ? ? 3. It will show us why gravitational mass and inertial mass are
> > > ? ? ? ? ? ? identical.
> > > ? ? ? ? ? ? 4. It will show us the speed of gravitational attraction.
> > > ? ?
> > > ? ? ? ? ? ? Newton said gravity was acting at a much faster speed than Einstein.
> > > ? ?
> > > ? ? ? ? ? Well, the average running speed of a human is around 10 mph. Sprints, the
> > > ? ? ? ? ? record is under 30 mph. I don't know how athletic Einstein was so we could
> > > ? ? ? ? ? use a figure of 3 mph walking speed. Nice to set some lower boundaries
> > > ? ? ? ? ? on the SoG (speed of gravity).
> > > ? ?
> > > ? ? ? ? Slow Old Geezers.
> > > ? ?
> > > ? ? ? I resemble that remark!
> > > ? ?
> > > ? ? Admitting it is the first step to recovery! ;-)
> > > ?
> > > ? There is no recovery...slow, old geezers only get slower.
> > >
> > > And older...
> >
> > The alternative is worse...
>
> There is no alternative. Not really ;)

The alternative is that long 'final nap', underground.

--
Politicians should only get paid if the budget is balanced, and there is
enough left over to pay them.

==============================================================================
TOPIC: Weird stuff -- update -- (was Electronic Kenmore refrigerator not
working, what does this sign mean)
http://groups.google.com/group/sci.electronics.repair/t/90e33648f2879de5?hl=en
==============================================================================

== 1 of 8 ==
Date: Fri, Sep 3 2010 3:04 am
From: "kfvorwerk@gmail.com"

On Sep 2, 2:14 pm, rangerssuck <rangerss...@gmail.com> wrote:
> No doubt someone mor knowledgable will have something to add here, but
> it sounds like the compressor is trying to start against a load. How
> long was it unplugged while you were replacing the cover? I imagine it
> should be unplugged at least three ininutes, and probably five.
> However, I'd also imagine that there would be a timer of some sort to
> prevent short-cycling. Of course, the thermal protection in the motor
> would kick in eventually, but my air conditioner, for example, simply
> will not run the compressor for a few minutes after you plug it in if
> it had been running just prior to unplugging.
>
> Anyway, I'd suggest that you let it rest a few minutes and then try
> again.

I seem to remember I was told that you should keep it unplugged 1/2
hour.
Karl

== 2 of 8 ==
Date: Fri, Sep 3 2010 4:06 am
From: Hugh Jassolle

On Thu, 02 Sep 2010 19:03:20 -0500, Ignoramus28169 wrote:

> Things are getting weirder and weirder. My original post is at the
> bottom.
>
> I have received the replacement relay and capacitor today.
>
> Installed them (it was a 2 minute job).
>
> Plugged in the fridge.
>
> The compressor happily started working normally, mildly vibrating and
> indicating in all respects that it is running fine.
>
> Happy after 2 minutes, I turned off the fridge, and reinstalled the rear
> insulated covering panel and ground.
>
> Plugged in again and I HEARD THE SAME OLD DREADED BUZZING SOUND. Now,
> the compressor motor would not start again! It busses fomr several
> seconds and the relay clicks and turns it off.
>
> I am completely puzzled as to why exactly it turned on once, but would
> not turn on again.
>
> Any idea?

Call Sears repair.

== 3 of 8 ==
Date: Fri, Sep 3 2010 4:11 am
From: Archon

On 9/2/2010 8:03 PM, Ignoramus28169 wrote:
> Things are getting weirder and weirder. My original post is at the bottom.
>
> I have received the replacement relay and capacitor today.
>
> Installed them (it was a 2 minute job).
>
> Plugged in the fridge.
>
> The compressor happily started working normally, mildly vibrating and
> indicating in all respects that it is running fine.
>
> Happy after 2 minutes, I turned off the fridge, and reinstalled the
> rear insulated covering panel and ground.
>
> Plugged in again and I HEARD THE SAME OLD DREADED BUZZING SOUND. Now,
> the compressor motor would not start again! It busses fomr several
> seconds and the relay clicks and turns it off.
>
> I am completely puzzled as to why exactly it turned on once, but would
> not turn on again.
>
> Any idea?
>
> i

Hi, Good to hear the overload relay worked for you, (I read your later
post where everything seems to be working ok)

As I didn't trust the freezer after my repair I purchased one of these

http://cgi.ebay.com/TA20-CDN-Freezer-Alarm-Alert-Digital-Thermometer-5yrW-/300378854590?pt=LH_DefaultDomain_0&hash=item45eff994be

Its pretty neat and although I never had a problem afterwards, its good
to see the freezer temps.

== 4 of 8 ==
Date: Fri, Sep 3 2010 5:45 am
From: PeterD

On Thu, 02 Sep 2010 19:03:20 -0500, Ignoramus28169
<ignoramus28169@NOSPAM.28169.invalid> wrote:

>Things are getting weirder and weirder. My original post is at the bottom.
>
>I have received the replacement relay and capacitor today.
>
>Installed them (it was a 2 minute job).
>
>Plugged in the fridge.
>
>The compressor happily started working normally, mildly vibrating and
>indicating in all respects that it is running fine.
>
>Happy after 2 minutes, I turned off the fridge, and reinstalled the
>rear insulated covering panel and ground.
>
>Plugged in again and I HEARD THE SAME OLD DREADED BUZZING SOUND. Now,
>the compressor motor would not start again! It busses fomr several
>seconds and the relay clicks and turns it off.
>
>I am completely puzzled as to why exactly it turned on once, but would
>not turn on again.
>
>Any idea?
>
>i

hell, my fridge has done that for years... (Really, it has).

The reason is 'high head pressure' and you have to let it sit for as
much as 20 to 30 minutes (typically, but can be longer) between
startup cycles.

== 5 of 8 ==
Date: Fri, Sep 3 2010 5:45 am
From: PeterD

On Thu, 02 Sep 2010 20:12:37 -0500, Ignoramus28169
<ignoramus28169@NOSPAM.28169.invalid> wrote:

>On 2010-09-03, Ignoramus28169 <ignoramus28169@NOSPAM.28169.invalid> wrote:
>> Things are getting weirder and weirder. My original post is at the bottom.
>>
>> I have received the replacement relay and capacitor today.
>>
>> Installed them (it was a 2 minute job).
>>
>> Plugged in the fridge.
>>
>> The compressor happily started working normally, mildly vibrating and
>> indicating in all respects that it is running fine.
>>
>> Happy after 2 minutes, I turned off the fridge, and reinstalled the
>> rear insulated covering panel and ground.
>>
>> Plugged in again and I HEARD THE SAME OLD DREADED BUZZING SOUND. Now,
>> the compressor motor would not start again! It busses fomr several
>> seconds and the relay clicks and turns it off.
>>
>> I am completely puzzled as to why exactly it turned on once, but would
>> not turn on again.
>>
>> Any idea?
>
>Oddly enough, after waiting for a while, it started fine and is
>cooling down at an acceptable rate.
>
>i
>

Not odd, high head pressure was doing it. Considered normal in most
applications.

== 6 of 8 ==
Date: Fri, Sep 3 2010 6:04 am
From: Hugh Jassolle

On Fri, 03 Sep 2010 08:45:03 -0400, PeterD wrote:

> On Thu, 02 Sep 2010 19:03:20 -0500, Ignoramus28169
> <ignoramus28169@NOSPAM.28169.invalid> wrote:
>
>>Things are getting weirder and weirder. My original post is at the
>>bottom.
>>
>>I have received the replacement relay and capacitor today.
>>
>>Installed them (it was a 2 minute job).
>>
>>Plugged in the fridge.
>>
>>The compressor happily started working normally, mildly vibrating and
>>indicating in all respects that it is running fine.
>>
>>Happy after 2 minutes, I turned off the fridge, and reinstalled the rear
>>insulated covering panel and ground.
>>
>>Plugged in again and I HEARD THE SAME OLD DREADED BUZZING SOUND. Now,
>>the compressor motor would not start again! It busses fomr several
>>seconds and the relay clicks and turns it off.
>>
>>I am completely puzzled as to why exactly it turned on once, but would
>>not turn on again.
>>
>>Any idea?
>>
>>i
>
> hell, my fridge has done that for years... (Really, it has).
>
> The reason is 'high head pressure' and you have to let it sit for as
> much as 20 to 30 minutes (typically, but can be longer) between startup
> cycles.

Shouldn't take 20 minutes for the head pressure to bleed off enough for a
restart. Unless of course there is a partial restriction in the high
side. If the system has moisture in the freon the end of the cap tube can
ice up causing a restriction. Or some contaminates could plug the cap
tube partially. Normally the head pressure should reduce sufficiently to
allow a proper working compressor to restart in 5 minutes or less.

== 7 of 8 ==
Date: Fri, Sep 3 2010 7:06 am
From: DerbyDad03

On Sep 2, 8:30 pm, aemeijers <aemeij...@att.net> wrote:
> On 9/2/2010 8:03 PM, Ignoramus28169 wrote:
>
>
>
> > Things are getting weirder and weirder. My original post is at the bottom.
>
> > I have received the replacement relay and capacitor today.
>
> > Installed them (it was a 2 minute job).
>
> > Plugged in the fridge.
>
> > The compressor happily started working normally, mildly vibrating and
> > indicating in all respects that it is running fine.
>
> > Happy after 2 minutes, I turned off the fridge, and reinstalled the
> > rear insulated covering panel and ground.
>
> > Plugged in again and I HEARD THE SAME OLD DREADED BUZZING SOUND. Now,
> > the compressor motor would not start again! It busses fomr several
> > seconds and the relay clicks and turns it off.
>
> > I am completely puzzled as to why exactly it turned on once, but would
> > not turn on again.
>
> > Any idea?
>
> Take the cover back off and see if anything changes? Mebbe fridge got
> shoved into the wall, and the cover got bent, and is making something
> not work?
>
> I'm no fridge expert, but when something stops working when you put the
> lid on, that tells me the lid is somehow binding something up or
> shorting something out.
>
> --
> aem sends...

re: "when something stops working when you put the lid on, that tells
me the lid is somehow binding something up or shorting something out."

In a much earlier life, I used to install and repair Radio Shack
TRS-80 workstations. My company also used the Storage Expansion Unit
which could house up to three additional 8″ drives as shown here:

http://www.trs-80.com/wordpress/trs-80-computer-line/model-ii/

These expansion bays were notorious for not working once you put the
cover back on. You'd repair the unit or add a drive, test all three
drives with the cover off and then install the cover and the 84,000
screws that kept it on. Invariably, one of the drives (it would be
random as to which one) would no longer be accessible.

You had to loosen screws, tweak the cover, slap the box, whatever, to
get it working.

With hundreds of these workstations installed in everything from
offices to chemical processing areas, you can be sure that we did a
lot of bench work trying to determine what the problem was in an
effort to make our on-site work easier. We never figured it out and
were thrilled when they started replacing them with the original IBM
PC.

== 8 of 8 ==
Date: Fri, Sep 3 2010 8:33 am
From: Bob Villa

On Sep 3, 7:06 am, DerbyDad03 <teamarr...@eznet.net> wrote:
> On Sep 2, 8:30 pm, aemeijers <aemeij...@att.net> wrote:
>
>
>
> > On 9/2/2010 8:03 PM, Ignoramus28169 wrote:
>
> > > Things are getting weirder and weirder. My original post is at the bottom.
>
> > > I have received the replacement relay and capacitor today.
>
> > > Installed them (it was a 2 minute job).
>
> > > Plugged in the fridge.
>
> > > The compressor happily started working normally, mildly vibrating and
> > > indicating in all respects that it is running fine.
>
> > > Happy after 2 minutes, I turned off the fridge, and reinstalled the
> > > rear insulated covering panel and ground.
>
> > > Plugged in again and I HEARD THE SAME OLD DREADED BUZZING SOUND. Now,
> > > the compressor motor would not start again! It busses fomr several
> > > seconds and the relay clicks and turns it off.
>
> > > I am completely puzzled as to why exactly it turned on once, but would
> > > not turn on again.
>
> > > Any idea?
>
> > Take the cover back off and see if anything changes? Mebbe fridge got
> > shoved into the wall, and the cover got bent, and is making something
> > not work?
>
> > I'm no fridge expert, but when something stops working when you put the
> > lid on, that tells me the lid is somehow binding something up or
> > shorting something out.
>
> > --
> > aem sends...
>
> re: "when something stops working when you put the lid on, that tells
> me the lid is somehow binding something up or shorting something out."
>
> In a much earlier life, I used to install and repair Radio Shack
> TRS-80 workstations. My company also used the Storage Expansion Unit
> which could house up to three additional 8″ drives as shown here:
>
> http://www.trs-80.com/wordpress/trs-80-computer-line/model-ii/
>
> These expansion bays were notorious for not working once you put the
> cover back on. You'd repair the unit or add a drive, test all three
> drives with the cover off and then install the cover and the 84,000
> screws that kept it on. Invariably, one of the drives (it would be
> random as to which one) would no longer be accessible.
>
> You had to loosen screws, tweak the cover, slap the box, whatever, to
> get it working.
>
> With hundreds of these workstations installed in everything from
> offices to chemical processing areas, you can be sure that we did a
> lot of bench work trying to determine what the problem was in an
> effort to make our on-site work easier. We never figured it out and
> were thrilled when they started replacing them with the original IBM
> PC.

Many of these kinds of things end up being cracked connector solder or
chips that fail when heated. BTDT

==============================================================================
TOPIC: Yet another bulging-capacitors replacement
http://groups.google.com/group/sci.electronics.repair/t/3ec97de65fce9bb3?hl=en
==============================================================================

== 1 of 3 ==
Date: Fri, Sep 3 2010 4:31 am
From: "Arfa Daily"

"Jeff Liebermann" <jeffl@cruzio.com> wrote in message
news:11n086hmsc5jvt998a8jr9t3nel9md1ea7@4ax.com...
> On Fri, 3 Sep 2010 02:04:18 +0100, "Arfa Daily"
> <arfa.daily@ntlworld.com> wrote:
>
>>
>>
>>"Jeff Liebermann" <jeffl@cruzio.com> wrote in message
>>news:avlv76lbbv730nj64qmotl19k485ah8ji4@4ax.com...
>>> On Thu, 02 Sep 2010 09:54:44 -0700, Jeff Liebermann <jeffl@cruzio.com>
>>> wrote:
>>>
>>>>The thermal conductivity of G10/FR4 isn't all that wonderful,
>>> (...)
>>>
>>> Ok, let's do the numbers. The coefficient of thermal expansion for
>>> G10/FR4 is:
>>> 1*10^-5 cm/cm/C
>>> That means a 1 cm long piece of G10/FR4, will expand 1*10^-5 cm for
>>> every degree C of temperature differential.
>>>
>>> So, we have a big fat BGA chip, that's about 5cm across. It's running
>>> hot with a bottom temperature of about 80C. Assuming the PCB is
>>> running at room temp of 25C, that's a 55C differential temperature.
>>> Over the diameter of the BGA, that's
>>> 125*10^-5 cm
>>> movement of the PCB.
>>>
>>> Solder balls come in all manner of sizes, but my guess(tm) that for a
>>> 1mm pitch BGA, a 0.4mm ball is appropriate. When soldered, the ball
>>> will remain about the same diameter, but the height will be reduced to
>>> about 0.1mm.
>>>
>>> The angle that the ball moves over temperature is:
>>> angle = arctan ( 125*10^-5 cm / 0.01cm ) = arctan 0.125
>>> angle = 7 degrees
>>> which is a fair amount of ball rotation. Do that often enough, and
>>> the ball will "roll" itself off the pad. For a sanity check, solder a
>>> rigid bar of something to a flat surface, and bend it back and forth
>>> about 7 degrees. It will take a while, but it will eventually break.
>
>>Great info and insights in both posts as always Jeff. I will take them
>>into
>>consideration. The temperature differential thing is something that I
>>hadn't
>>considered, but following through your numbers, seems to be a very valid
>>point ...
>
> Well, I did manage to make one mistake. The 7 degrees is the worst
> case bending angle assuming everything accumulates in one direction.
> That's not the case as local heating of the PCB will be from the
> center outward. Instead of 125*10^-5 cm of lengthening measured from
> the edge, the PCB will elongate half that amount, measured from the
> center of the BGA. Correcting accordingly:
>
> The angle that the ball moves over temperature is:
> angle = arctan ( 63*10^-5 cm / 0.01cm ) = arctan 0.063
> angle = 3.5 degrees
> That's still enough to tear apart the solder ball, but not as radical
> as I previously suggested.
>
> One solution is to use a BGA adapter socket. Obviously, this isn't
> going to work inside a laptop, where vertical height is a major
> limitation. Same with some desktops, where the CPU heatsink and fan
> can only be so tall or air flow out the top of the heatsink and fan
> will be constricted. I've never tried to retrofit one of these into
> an existing motherboard, but it sure looks tempting.
> <http://www.advanced.com/bgastart.html>
> <http://www.mill-max.com/products/newproducts_detail.cfm?pid=7>
> <http://www.ironwoodelectronics.com/products/adapters/giga_snap.cfm>
>
>
> --
> Jeff Liebermann jeffl@cruzio.com

This is something that I was talking about with a colleague just a few days
ago. I'll take a look at the links. Going back to the differential heating
issue, I've thought a bit more about it, and it seems that the greatest
source of heat is going to be the top surface of the BGA itself, which has
the bonded heat dissipation plate for interfacing with the heatsink
assembly. Heat getting into the PCB is going to be two ways i.e. by
conduction through the solder balls, and by direct radiation from the
underside of the chip. Neither of these are going to be particularly
efficient, and I would expect as much heat as possible to be directed
upwards into the plate, by design. So it seems to me that the board is going
to remain relatively cool, compared to the underside of the BGA, and more to
the point, the upper side. So the hotter that the BGA is allowed to run, the
greater will be the undesired thermal difference between board and chip.
Therefore, any help to the cooling of the upper surface of the chip, should
help to reduce the temperature differential rather than exacerbate it,
shouldn't it ? To take it to its logical conclusion, if you could remove all
heat that the chip was generating, then there would be none to heat the
board, so there would be no thermal differential, at all ??

Arfa

== 2 of 3 ==
Date: Fri, Sep 3 2010 4:36 am
From: "Arfa Daily"

"Mike Tomlinson" <mike@jasper.org.uk> wrote in message
news:R+UXbOA7ZIgMFwrh@jasper.org.uk...
> In article <pXKfo.13668$45.9048@newsfe29.ams2>, Arfa Daily
> <arfa.daily@ntlworld.com> writes
>
>>I have always been sparing with compound - and I
>>use a lot of it as I repair many big amps for a living - but it is a fact
>>that a very thin translucent layer of white, is not effective enough on a
>>standard non-flatted device face, and heatsink contact area, whereas with
>>AS, it would appear that it is.
>
> Have you tried applying the white stuff to both surfaces, then scraping
> it off with the edge of a card? That will fill in any valleys on both
> surfaces, and you should get a good thermal bond with the minimum of
> compound.
>
> This is the method that AS suggest using, by the way.
>
> --
> (\__/)
> (='.'=)
> (")_(")
>
>

Yes Mike. Prior to starting to use the AS, I have always treated both
surfaces when using white, contrary to much perceived wisdom where it is
insisted that only one surface should be coated. I believe in doing both
surfaces for the exact same reasons that you cite. I am also doing both
surfaces with AS, but very sparingly. There are always milling patterns on
the heatsink faces on these machines, which I think is a bit bad on the part
of the manufacturers anyway, given the huge thermal loads that are produced
by these chips ...

Arfa

== 3 of 3 ==
Date: Fri, Sep 3 2010 5:11 am
From: Meat Plow

On Fri, 03 Sep 2010 12:36:34 +0100, Arfa Daily wrote:

> "Mike Tomlinson" <mike@jasper.org.uk> wrote in message
> news:R+UXbOA7ZIgMFwrh@jasper.org.uk...
>> In article <pXKfo.13668$45.9048@newsfe29.ams2>, Arfa Daily
>> <arfa.daily@ntlworld.com> writes
>>
>>>I have always been sparing with compound - and I use a lot of it as I
>>>repair many big amps for a living - but it is a fact that a very thin
>>>translucent layer of white, is not effective enough on a standard
>>>non-flatted device face, and heatsink contact area, whereas with AS, it
>>>would appear that it is.
>>
>> Have you tried applying the white stuff to both surfaces, then scraping
>> it off with the edge of a card? That will fill in any valleys on both
>> surfaces, and you should get a good thermal bond with the minimum of
>> compound.
>>
>> This is the method that AS suggest using, by the way.
>>
>> --
>> (\__/)
>> (='.'=)
>> (")_(")
>>
>>
>>
> Yes Mike. Prior to starting to use the AS, I have always treated both
> surfaces when using white, contrary to much perceived wisdom where it is
> insisted that only one surface should be coated. I believe in doing both
> surfaces for the exact same reasons that you cite. I am also doing both
> surfaces with AS, but very sparingly. There are always milling patterns
> on the heatsink faces on these machines, which I think is a bit bad on
> the part of the manufacturers anyway, given the huge thermal loads that
> are produced by these chips ...
>
> Arfa

I've never thought it necessary to coat both surfaces. If you use
sufficient paste on one it will suffice for both sides. Key word
sufficient but not overly so. I guess it's just something you develop
a knack for in knowing what is too much or not enough. This 120 watt
AMD 955 PhenomII chip in my PC runs in its normal temp range. Idles
around 43c. CPU fan runs at 2500rpm, half of 5000 at full speed automatic
control. What I'm getting at is the heatsink that comes with the chip
has a very thin coat of Arctic. And it seems to do very well being
applied to the heatsink side only.

--
Live Fast, Die Young and Leave a Pretty Corpse

==============================================================================
TOPIC: Plasma TV Foggy area
http://groups.google.com/group/sci.electronics.repair/t/9e5cdc2b5ff03be3?hl=en
==============================================================================

== 1 of 10 ==
Date: Fri, Sep 3 2010 7:45 am
From: "Michael Kennedy"

I don't have this tv in hand now and also don't have the make and model of
this display at the moment but all I am looking for is general information
for now.

This tv has a smudged / blurry area on the screen. It looks almost like it
is dirty from a oily hand but it doesn't wipe off. It is not a rectangular
area.

I am not familar with the common failure modes of Plasma displays. What is
your best guess would cause this.

Thanks in advance,

Mike

== 2 of 10 ==
Date: Fri, Sep 3 2010 8:00 am
From: Meat Plow

On Fri, 03 Sep 2010 23:45:09 +0900, Michael Kennedy wrote:

> I don't have this tv in hand now and also don't have the make and model
> of this display at the moment but all I am looking for is general
> information for now.
>
> This tv has a smudged / blurry area on the screen. It looks almost like
> it is dirty from a oily hand but it doesn't wipe off. It is not a
> rectangular area.
>
> I am not familar with the common failure modes of Plasma displays. What
> is your best guess would cause this.
>
> Thanks in advance,
>
> Mike

Since it only covers a non-symmetrical portion of the screen my
guestimate would be the screen itself.

--
Live Fast, Die Young and Leave a Pretty Corpse

== 3 of 10 ==
Date: Fri, Sep 3 2010 8:14 am
From: Randy Day

In article <VridnT16DI5klBzRnZ2dnVY3go2dnZ2d@giganews.com>,
mike@nospam.com says...
> I don't have this tv in hand now and also don't have the make and model of
> this display at the moment but all I am looking for is general information
> for now.
>
> This tv has a smudged / blurry area on the screen. It looks almost like it
> is dirty from a oily hand but it doesn't wipe off. It is not a rectangular
> area.
>
> I am not familar with the common failure modes of Plasma displays. What is
> your best guess would cause this.

Someone used solvent to clean the screen?

--- news://freenews.netfront.net/ - complaints: news@netfront.net ---

== 4 of 10 ==
Date: Fri, Sep 3 2010 8:18 am
From: "Michael Kennedy"

"Meat Plow" <mhywatt@yahoo.com> wrote in message
news:pan.2010.09.03.14.59.46@hahahahahahahah.nutz.I.am...
> On Fri, 03 Sep 2010 23:45:09 +0900, Michael Kennedy wrote:
>
>> I don't have this tv in hand now and also don't have the make and model
>> of this display at the moment but all I am looking for is general
>> information for now.
>>
>> This tv has a smudged / blurry area on the screen. It looks almost like
>> it is dirty from a oily hand but it doesn't wipe off. It is not a
>> rectangular area.
>>
>> I am not familar with the common failure modes of Plasma displays. What
>> is your best guess would cause this.
>>
>> Thanks in advance,
>>
>> Mike
>
> Since it only covers a non-symmetrical portion of the screen my
> guestimate would be the screen itself.
>

Thanks for the insight Meat.

These aren't affected by magnets the way CRT sets are they? Sorry for the
stupid questions, but I have never taken apart, owned or even used a plasma
display. I am only familiar with the VERY basic principles of operation and
know it uses phosphors which are similar to a CRT but uses some other method
to illuminate the phosphors. I guess uses some kind of micro printed
circuitry similar to an LCD display, but I could be totally wrong about
that.

== 5 of 10 ==
Date: Fri, Sep 3 2010 8:22 am
From: "Michael Kennedy"

"Randy Day" <randy.day@sasktel.netx> wrote in message
news:MPG.26eaccdb1b1fd1e19896c0@202.177.16.121...
> In article <VridnT16DI5klBzRnZ2dnVY3go2dnZ2d@giganews.com>,
> mike@nospam.com says...
>> I don't have this tv in hand now and also don't have the make and model
>> of
>> this display at the moment but all I am looking for is general
>> information
>> for now.
>>
>> This tv has a smudged / blurry area on the screen. It looks almost like
>> it
>> is dirty from a oily hand but it doesn't wipe off. It is not a
>> rectangular
>> area.
>>
>> I am not familar with the common failure modes of Plasma displays. What
>> is
>> your best guess would cause this.
>
> Someone used solvent to clean the screen?
>

Interesting idea.. That's a case where the screen could be fixed... I will
have a close look at it in a couple of days.
The price is right on this thing, but I don't want to sink money into it if
the screen is about to crap out.. Since that's the one piece that cant be
repaired.

== 6 of 10 ==
Date: Fri, Sep 3 2010 8:27 am
From: Meat Plow

On Sat, 04 Sep 2010 00:18:51 +0900, Michael Kennedy wrote:

> "Meat Plow" <mhywatt@yahoo.com> wrote in message
> news:pan.2010.09.03.14.59.46@hahahahahahahah.nutz.I.am...
>> On Fri, 03 Sep 2010 23:45:09 +0900, Michael Kennedy wrote:
>>
>>> I don't have this tv in hand now and also don't have the make and
>>> model of this display at the moment but all I am looking for is
>>> general information for now.
>>>
>>> This tv has a smudged / blurry area on the screen. It looks almost
>>> like it is dirty from a oily hand but it doesn't wipe off. It is not a
>>> rectangular area.
>>>
>>> I am not familar with the common failure modes of Plasma displays.
>>> What is your best guess would cause this.
>>>
>>> Thanks in advance,
>>>
>>> Mike
>>
>> Since it only covers a non-symmetrical portion of the screen my
>> guestimate would be the screen itself.
>>
>>
> Thanks for the insight Meat.
>
> These aren't affected by magnets the way CRT sets are they? Sorry for
> the stupid questions, but I have never taken apart, owned or even used
> a plasma display. I am only familiar with the VERY basic principles of
> operation and know it uses phosphors which are similar to a CRT but uses
> some other method to illuminate the phosphors. I guess uses some kind of
> micro printed circuitry similar to an LCD display, but I could be
> totally wrong about that.

The phosphors are illuminated by bursts of plasma emitting a UV light not
an electron beam. Cells are filled with gases including a small amount of
mercury. Each cell is capable of the three primary colors and depending
on the amount of electricity applied to the cell controls the intensity.
That's about it for my understanding.

--
Live Fast, Die Young and Leave a Pretty Corpse

== 7 of 10 ==
Date: Fri, Sep 3 2010 8:33 am
From: AZ Nomad

On Sat, 4 Sep 2010 00:18:51 +0900, Michael Kennedy <mike@nospam.com> wrote:

>Thanks for the insight Meat.

>These aren't affected by magnets the way CRT sets are they? Sorry for the
>stupid questions, but I have never taken apart, owned or even used a plasma
>display. I am only familiar with the VERY basic principles of operation and
>know it uses phosphors which are similar to a CRT but uses some other method
>to illuminate the phosphors. I guess uses some kind of micro printed
>circuitry similar to an LCD display, but I could be totally wrong about
>that.

There is no convergance nor is there any concept of focussing. The
pixels are fixed in size and location and nothing can affect that.

== 8 of 10 ==
Date: Fri, Sep 3 2010 8:38 am
From: "Michael Kennedy"

"Meat Plow" <mhywatt@yahoo.com> wrote in message
news:pan.2010.09.03.15.27.11@hahahahahahahah.nutz.I.am...
> On Sat, 04 Sep 2010 00:18:51 +0900, Michael Kennedy wrote:
>
>> "Meat Plow" <mhywatt@yahoo.com> wrote in message
>> news:pan.2010.09.03.14.59.46@hahahahahahahah.nutz.I.am...
>>> On Fri, 03 Sep 2010 23:45:09 +0900, Michael Kennedy wrote:
>>>
>>>> I don't have this tv in hand now and also don't have the make and
>>>> model of this display at the moment but all I am looking for is
>>>> general information for now.
>>>>
>>>> This tv has a smudged / blurry area on the screen. It looks almost
>>>> like it is dirty from a oily hand but it doesn't wipe off. It is not a
>>>> rectangular area.
>>>>
>>>> I am not familar with the common failure modes of Plasma displays.
>>>> What is your best guess would cause this.
>>>>
>>>> Thanks in advance,
>>>>
>>>> Mike
>>>
>>> Since it only covers a non-symmetrical portion of the screen my
>>> guestimate would be the screen itself.
>>>
>>>
>> Thanks for the insight Meat.
>>
>> These aren't affected by magnets the way CRT sets are they? Sorry for
>> the stupid questions, but I have never taken apart, owned or even used
>> a plasma display. I am only familiar with the VERY basic principles of
>> operation and know it uses phosphors which are similar to a CRT but uses
>> some other method to illuminate the phosphors. I guess uses some kind of
>> micro printed circuitry similar to an LCD display, but I could be
>> totally wrong about that.
>
> The phosphors are illuminated by bursts of plasma emitting a UV light not
> an electron beam. Cells are filled with gases including a small amount of
> mercury. Each cell is capable of the three primary colors and depending
> on the amount of electricity applied to the cell controls the intensity.
> That's about it for my understanding.
>

Hmm.. Interesting. Plasma bursts.Hence why it's called a Plasma display..
Thanks for the basic run down.

== 9 of 10 ==
Date: Fri, Sep 3 2010 8:40 am
From: "Michael Kennedy"

"AZ Nomad" <aznomad.3@PremoveOBthisOX.COM> wrote in message
news:slrni825ad.gkr.aznomad.3@ip70-176-155-130.ph.ph.cox.net...
> On Sat, 4 Sep 2010 00:18:51 +0900, Michael Kennedy <mike@nospam.com>
> wrote:
>
>>"Meat Plow" <mhywatt@yahoo.com> wrote in message
>>news:pan.2010.09.03.14.59.46@hahahahahahahah.nutz.I.am...
>>> On Fri, 03 Sep 2010 23:45:09 +0900, Michael Kennedy wrote:
>>>
>>>> I don't have this tv in hand now and also don't have the make and model
>>>> of this display at the moment but all I am looking for is general
>>>> information for now.
>>>>
>>>> This tv has a smudged / blurry area on the screen. It looks almost like
>>>> it is dirty from a oily hand but it doesn't wipe off. It is not a
>>>> rectangular area.
>>>>
>>>> I am not familar with the common failure modes of Plasma displays. What
>>>> is your best guess would cause this.
>>>>
>>>> Thanks in advance,
>>>>
>>>> Mike
>>>
>>> Since it only covers a non-symmetrical portion of the screen my
>>> guestimate would be the screen itself.
>>>
>
>>Thanks for the insight Meat.
>
>>These aren't affected by magnets the way CRT sets are they? Sorry for the
>>stupid questions, but I have never taken apart, owned or even used a
>>plasma
>>display. I am only familiar with the VERY basic principles of operation
>>and
>>know it uses phosphors which are similar to a CRT but uses some other
>>method
>>to illuminate the phosphors. I guess uses some kind of micro printed
>>circuitry similar to an LCD display, but I could be totally wrong about
>>that.
>
> There is no convergance nor is there any concept of focussing. The
> pixels are fixed in size and location and nothing can affect that.

That's the question I was wondering.. Thanks!
I've got a little better idea of how this thing works now. Before it was
all speculation.

== 10 of 10 ==
Date: Fri, Sep 3 2010 8:47 am
From: "Michael Kennedy"

==============================================================================
TOPIC: LORAN C
http://groups.google.com/group/sci.electronics.repair/t/73c2d1e0342e191b?hl=en
==============================================================================

== 1 of 1 ==
Date: Fri, Sep 3 2010 7:48 am
From: "Michael Kennedy"

"GregS" <zekfrivo@zekfrivolous.com> wrote in message
news:i5m6pq$jf8$1@usenet01.srv.cis.pitt.edu...
> In article <mu0t761s85hgq8f1vnv3vhelfppfc43af4@4ax.com>, Jeff Liebermann
> <jeffl@cruzio.com> wrote:
>>On Wed, 1 Sep 2010 10:30:59 +0100, "N_Cook" <diverse@tcp.co.uk> wrote:
>>
>>>I hope LW RDF is still going , I liked the morse ident feature and its
>>>simplicity. I doubt , over some distance , it is any less accurate than
>>>Loran and no hyperbolic plots to deal with
>>
>>Yep. They're still alive and well. I still have a Taiho automagic
>>mechanically rotating LW RDF that I use for demonstrations. It's fun
>>to watch the loop seek and maybe point. Some of the LW beacon
>>stations are sending DGPS which have largely been replaced by WAAS
>>technology. Hearing LW beacons more than a few miles from shore is
>>tricky without a big antenna. You would probably be more successful
>>using AM, FM, and TV stations for coastline navigation, than using the
>>few LW stations.
>><http://www.beaconworld.fotopic.net/list_collections.php>
>
> If we got a big solar storm, and most or all satellites got knocked out,
> along with ground power, the beacons may be the only route home.
>
> I remember having to record Loran D, just another experimental site.
>
> <snip>

My thoughs exactly.. Unfortuantely loran could have been a backup
useful for boats and airplanes within the range of the system.

==============================================================================

You received this message because you are subscribed to the Google Groups "sci.electronics.repair"
group.

To post to this group, visit http://groups.google.com/group/sci.electronics.repair?hl=en

To unsubscribe from this group, send email to sci.electronics.repair+unsubscribe@googlegroups.com

To change the way you get mail from this group, visit:
http://groups.google.com/group/sci.electronics.repair/subscribe?hl=en

To report abuse, send email explaining the problem to abuse@googlegroups.com

==============================================================================
Google Groups: http://groups.google.com/?hl=en

Electronics

sci.electronics.repair - 25 new messages in 6 topics - digest

No Response to "sci.electronics.repair - 25 new messages in 6 topics - digest"

Post a Comment

Blog Roll

Blog Archive