Toshiba TV29C90 problem; Image fades to black...

[Jeff Liebermann]

On Thu, 10 Jan 2019 08:55:55 -0500, Pat <forums@greensdomain.com>
wrote:

I have a question. How can "static" be
a symptom of dirty tape heads? Drop outs - yes. Loss of highs - yes.
Static? Sounds more like a bad connection or static electricity being
generated somewhere.

There's quite a bit to be found using Google search on the topic:
<https://www.google.com/search?q=tape+head+static+electricity>
The motion of the mylar tape backing over the resin filled head tends
to build up a static charge on the tape. Metal reels and tape
cartridges will discharge most of this, but plastic reels and collect
static.

In high tech tape backup drives, such as LTO type drives, it is
possible for the static electricity to fry the heads.
<https://www.streetdirectory.com/travel_guide/116367/data_recovery/sony_lto_tape_storage_media.html>
"The working of the MR head is very much disturbed by
the static electricity, and the MR head can be destroyed
even by a minute static charge electricity."


--
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

 

On Thu, 10 Jan 2019 08:07:13 -0000 (UTC), gregz <ze...@comcast.net>
wrote:

Heads have some insulating material imbedded. Real rubbing alcohol is
supposed to have oil to prevent skin drying too much. Most don't. Isopropyl
or ethyl cleans heads.
Greg

Suffice it to say that using a substance for a purpose not mentioned on the container’s label just isn’t what you want. Go to a trusted computer or parts retailer and specifically ask for ’parts cleaner’, ‘head cleaner’ .. etc. Because it beats re-inventing the wheel, being adventuresome, gambling, etc...

 

[pfjw@aol.com]

On Monday, January 14, 2019 at 10:02:07 AM UTC-5, bruce2...@gmail.com wrote:

> Suffice it to say that using a substance for a purpose not mentioned on the container’s label just isn’t what you want. Go to a trusted computer or parts retailer and specifically ask for ’parts cleaner’, ‘head cleaner’ .. etc. Because it beats re-inventing the wheel, being adventuresome, gambling, etc...

There is always that.

But: Windex (a trusted name-brand cleaner) is:

Ammonia
Isopropyl Alcohol
Blue Dye
Water

Not very much of the first three, either.

Most of those here are at least somewhat sophisticated in the use of search engines. Some of us even fix things on occasion. Point being that with a small amount of research and time, we may be capable of formulating perfectly adequate cleaning solutions that are also both safe and effective. Typically, when we do this successfully, the results are fine, the costs low, and environmental impacts minimized. All good. The only significant caution(s) would be to be absolutely sure we understand the ingredients involved.

Peter Wieck
Melrose Park, PA

 

On Monday, 14 January 2019 15:02:07 UTC, bruce2...@gmail.com wrote:

On Thu, 10 Jan 2019 08:07:13 -0000 (UTC), gregz <ze...@comcast.net
wrote:

Suffice it to say that using a substance for a purpose not mentioned on the container’s label just isn’t what you want. Go to a trusted computer or parts retailer and specifically ask for ’parts cleaner’, ‘head cleaner’ .. etc. Because it beats re-inventing the wheel, being adventuresome, gambling, etc...

You won't do very well in life with that attitude.


NT

 

[Fox's Mercantile]

On 1/14/19 10:03 AM, tabbypurr@gmail.com wrote:

On Monday, 14 January 2019 15:02:07 UTC, bruce2...@gmail.com wrote:
Suffice it to say that using a substance for a purpose not
mentioned on the container’s label just isn’t what you want.
Go to a trusted computer or parts retailer and specifically
ask for ’parts cleaner’, ‘head cleaner’ .. etc. Because it
beats re-inventing the wheel, being adventuresome, gambling,
etc...

You won't do very well in life with that attitude.

NT

Actually, I do quite well with that attitude.
I buy things that work.

That way I don't have to waste my time and money playing "Mr.
Wizard."




--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com

 

[Jeff Liebermann]

On Mon, 14 Jan 2019 07:02:04 -0800 (PST), bruce2bowser@gmail.com
wrote:

Suffice it to say that using a substance for a purpose not mentioned
on the container’s label just isn’t what you want. Go to a trusted
computer or parts retailer and specifically ask for ’parts cleaner’,
‘head cleaner’ .. etc.

Three problems:
1. I don't know of any computer or parts retailer that I would trust.
2. I once asked for "head cleaner" and was presented with a bottle of
shampoo.
3. Everyone reads the label only after the product has been consumed.

--
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

 

On Monday, 14 January 2019 16:51:05 UTC, Fox's Mercantile wrote:

On 1/14/19 10:03 AM, tabbypurr wrote:
On Monday, 14 January 2019 15:02:07 UTC, bruce2...@gmail.com wrote:

Suffice it to say that using a substance for a purpose not
mentioned on the container’s label just isn’t what you want.
Go to a trusted computer or parts retailer and specifically
ask for ’parts cleaner’, ‘head cleaner’ .. etc. Because it
beats re-inventing the wheel, being adventuresome, gambling,
etc...

You won't do very well in life with that attitude.

NT

Actually, I do quite well with that attitude.
I buy things that work.

That way I don't have to waste my time and money playing "Mr.
Wizard."

I've learnt something today. I wasn't aware that paying a tenth the price for a better & entirely customisable product was a form of wizardry. Nor that it wasted time or money.

Retail concoctions often work, but often not adequately IME. Really it never ceases to amaze me what people pay for mostly water.


NT

 

[pfjw@aol.com]

What it comes down to is that there are not a lot of different cleaning materials out there. There are, however, very nearly infinite variations on a very, very few themes. Nothing is magical. And nothing is special in any meaningful way. There are companies that invest heavily in "proprietary" formula, some of which actually work well, and some of which do not. But every single one of them will start with what is most likely the same 20 or so basic materials. And nothing is secret. Do you really think that no other manufacturer has never dumped a drop of DeOxit into a gas chromatograph? Or a drop of Cramolin Red? Or any other solvent, chemical or material?

What is, more importantly, what is not in these magic formula is not magic. The Virgins that do the mixing only on Walpurgis Night are the stuff of legends, not fact-based. Nor do we have to be Mr. Wizard as we approach this. We need to understand some basic chemistry, understand the materials at hand and in use, and understand how any chemical reactions as may take place start, and more importantly, finish. Not a complicated process. We need to understand how chemical mix, what happens to the mix over time, and when applied, how they operate. Not a complicated process, either.

We have choices. Unlike Jeff, I am not in the fee-for-service aspect of the hobby. So, I do not have to warrant anything. Were I to, you bet that anything I used on my bench would be a supportable name-brand product designed for the use-at-hand. So, I may hand-mix a Cramolin-Red analog to my own needs. Or use some glacial ammonia to strip a really nasty part down to its bones. To me, the alternative is landfill - so "kill-or-cure" is not an idle statement.

But I do know my chemistry - at least as it applies to "heads" of various natures.

Peter Wieck
Melrose Park, PA

 

[Martin Gregorie]

On Mon, 14 Jan 2019 10:10:38 -0800, Jeff Liebermann wrote:

On Mon, 14 Jan 2019 07:02:04 -0800 (PST), bruce2bowser@gmail.com wrote:

3. Everyone reads the label only after the product has been consumed.

Another way to find out what's in a product it to read its Materials Data
Sheet (MSDS) - any substance that's transported before being sold or used
will have one because its often a condition of transport contracts that
it has one. Here's a good starting point:https://www.msdsonline.com/

https://hazard.com/msds/index.php
https://www.msdsonline.com/

.... but unfortunately the first of these is somewhat flaky - quite
possibly related to the US Governmental shutdown, since its been good in
the past.


--
Martin | martin at
Gregorie | gregorie dot org

 

[Fox's Mercantile]

On 1/14/19 1:46 PM, pfjw@aol.com wrote:

Unlike Jeff, I am not in the fee-for-service aspect of the
hobby. So, I do not have to warrant anything. Were I to,
you bet that anything I used on my bench would be a
supportable name-brand product designed for the use-at-hand.

I go through this same argument about using SnapOn tools vs
Craftsman. "But Craftsman is lifetime warranty too."
Perhaps, but I've never had to stop in the middle of a job
and hunt down a SnapOn tool dealer to replace something that
shouldn't have broken in the first place.

I make a living with my tools and materials. NOT standing in
line replacing things.



--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com

 

[Jeff Liebermann]

On Mon, 14 Jan 2019 11:38:06 -0800 (PST), tabbypurr@gmail.com wrote:

I've learnt something today. I wasn't aware that paying a tenth
the price for a better & entirely customisable product was a
form of wizardry. Nor that it wasted time or money.

I have a book "Fortunes in Formula" (1939). 853 pages and 10,000
formulas. It has just about everything one might want from cleaning
formulas to medical concoctions. It has served me well over the
years. Unfortunately, it uses the "common" names for chemicals. For
example:
aqua fortis = nitric acid
horn silver = sliver chloride
oil of vitriol = sulphuric acid
sugar of lead = lead acetate
verdigris = copper acetate
The medical preparation section uses the Latin names for everything.
Decoding the formulas does require an extra step in translation, but
is survivable.

A recent example of home chemistry is my annual problem with moss
growing on my wood outside stairs. The moss turns to slime when the
light and temperature is right, making my stairs rather hazardous.
I've been using the overpriced commercial preparation, which works,
but not very well. This year, I decided to try something from the
book, which turned out to be a vinegar, washing soda, salt, and water
preparation. It didn't work well in my sprayer, but it worked much
better than anything else I've dried with a scrub brush and garden
hose. My guess is I saved about $40 by essentially replacing the
commercial preparation with hardware store vinegar.

>Retail concoctions often work, but often not adequately IME.

Yep. I've had the same experience.

>Really it never ceases to amaze me what people pay for mostly water.

When I was young, stupid, and impoverished, I did some work for a
neighbor helping him prepare a laundry product in his garage. The
work was boring, but the owner had me fascinated with his stories
about his WWII TNT factory. The laundry ingredients were initially
fairly common and easily mixed. Yes, it was mostly water. However,
there were obscure additives that were quite necessary, usually to
solve uncommon or odd problems. The customers were getting mostly
water, but the common ingredients and obscure additives were what they
really were buying. The product eventually became a commercial
success and was sold to a large conglomerate.

--
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

 

[Fox's Mercantile]

On 1/14/19 3:50 PM, Jeff Liebermann wrote:

Yes, it was mostly water. However, there were obscure additives
that were quite necessary, usually to solve uncommon or odd
problems. The customers were getting mostly water, but the
common ingredients and obscure additives were what they really
were buying.

Exactly. I am more than happy to pay for stuff that works instead
of mucking about trying to "make my own."

Two things of note, brake fluid really does stop weeds in your
driveway cracks, and lamp oil (paraffin oil) is considerably
cheaper than Saddle Soap.

I did learn how to make Prussic Acid, but that's pretty iffy.
I'd rather my enemies drop dead from natural causes or through
their own misfortune.



--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com

 

On Monday, 14 January 2019 23:05:12 UTC, Fox's Mercantile wrote:

On 1/14/19 3:50 PM, Jeff Liebermann wrote:

Yes, it was mostly water. However, there were obscure additives
that were quite necessary, usually to solve uncommon or odd
problems. The customers were getting mostly water, but the
common ingredients and obscure additives were what they really
were buying.

Exactly. I am more than happy to pay for stuff that works instead
of mucking about trying to "make my own."

I have more success with my own formulations than retail preparations, mostly at far less cost. I don't see any upside to going retail. I'll use them when they're good, eg washing powder, but many things it's easy to do better. Retail descalers are especially time & money wasting.


NT

 

On Monday, January 14, 2019 at 11:03:39 AM UTC-5, tabb...@gmail.com wrote:

On Monday, 14 January 2019 15:02:07 UTC, bruce2...@gmail.com wrote:
On Thu, 10 Jan 2019 08:07:13 -0000 (UTC), gregz <ze...@comcast.net
wrote:

Suffice it to say that using a substance for a purpose not mentioned on the container’s label just isn’t what you want. Go to a trusted computer or parts retailer and specifically ask for ’parts cleaner’, ‘head cleaner’ .. etc. Because it beats re-inventing the wheel, being adventuresome, gambling, etc...

You won't do very well in life with that attitude.

I humbly disagree.

 

You got to be fucking kidding.

Well almost...

 

[N_Cook]

On 31/01/2019 21:47, William Beaty wrote:

I PERFORMED IC SURGERY on an analog amplifier, custom dip-16. Removed
the gold cover. Pretty huge 1980s stuff, gold-on-ceramic hybrid.
But still. This was a custom IC, a patchclamp front end with a peltier-
cooled discrete amp, with a tiny peltier block, thermistor, and a
three-jfets diff amp. And a large piece of a dessicant pellet.
The thermistor had gone crazy from old age, shutting down
their -30C cooling.

axopatch photos
http://staff.washington.edu/wbeaty/chem_axopatch.html#photo

I've never had leadbond chips open before. I mean, besides looking
inside those ancient Western Digital 6805-type microcontrollers with
the eprom window.

Mantis inspection microscopes: still NOT cheap on eBay.



((((((((((((((((((((((( ( ( (o) ) ) )))))))))))))))))))))))
William J. Beaty Research Engineer
beaty a chem washington edu UW Chem Dept, Bagley Hall RM74
billb a eskimo com Box 351700, Seattle, WA 98195-1700
ph x3-6195 http://staff.washington.edu/wbeaty/

What state was the dessicant?
I expected it to be the cause going to gel , like the breakdown of
con-formal coating causing chip failure.
I vaguely remember repairing an STK???? hybrid IC,fairly easy to break
open, that had been dropped and getting away with "bonding" the failed
usonic weld point , with silver loaded paint.

 

[Ron D.]

Cool. Surgeries are done on internal battery backed up Dallas RAMS too to access the pins for the battery, The new battery is placed on top.

If you have the map where to remove the Epoxy, You stand a good chance of repair.

Desoldering the chip (heating it) might destroy it's contents.

FYI and ASIDE: Had an ultrasonic bonder at work to play with, but it did not work well.

 

On Tuesday, October 15, 1996 at 3:00:00 AM UTC-4, Paul Atwell wrote:

Hello,
I have an Eye of the Storm, ionized glass globe, that has a blown flyback
transformer. The globe was manufactured by Rabbit Systems of (I believe)
California. This company used to make gadgets for TVs, VCRs, home stereos,
and their realted IR remotes. Attempts to find this company have failed.

Does anyone know where Rabbit Systems is now, or what happened to them?
Or, does anyone know a good supplier of flyback transformers?

Any news would be greatly appreciated!! Thank You! ---Paul

 

[micky]

To recap for the scientists: What size fuse to use in a 22V microwave:

In alt.home.repair, on Thu, 28 Mar 2019 19:07:29 -0500, Dean Hoffman
<dh0496@windstream.net> wrote:

On 3/28/19 7:00 PM, hubops@ccanoemail.ca wrote:


12a

Okay. I'll look for 12 amps, I'm glad I asked.
But I may have to settle for 10.


Yep - the problem that caused the 12 amp to blow
has surely cleared itself up by now - so a 10 amp is perfect !
.. or not. >> John T.

I suspect that was tongue in cheek. If not, fuses fail just
like everything else involving humans. I've changed a lot of them over the years
without having to do anything else.

LOL. I wasn't living here when it broke; I don't know what they did to
it.

By the same token, I'm leaving and I wanted to either put in the right
fuse or leave a note inside the case for the new owner (my roommate
already bought a replacement and they plan to put this one in the lobby
for someone to take.)

The second store I called had it, even 12 amps, not just 10, but as I
expected, only fast-blow. The original was ceramic.

I thought all ceramic fuses were slo-blo, but this one is embossed
F12H250 and some webpages say that F means fast-blow????
"The types of fuses include long-time-lag or super-time-lag (TT),
fast-acting fuses (FF), quick-blow fuses (F) and slow-blow or time-lag
fuses (T)"
https://www.hunker.com/13418825/difference-between-ceramic-glass-fuses

Nothing I read decribes why a microwave should need ceramic or slow-blo
(in the power part, not the high voltage part).

One page says " Glass has a low rupturing point, such as 15 amperes."

That's fine since it's a 12 amp fuse, and the normal usage is about 7
amps.

" If a high voltage comes down the electrical line, the fuse element
will melt.

Are there really surges that come down the line that increase the
amperage for normally 7 to over 12?

"The tiny glass fuses are great for small items that don't draw a heavy
amount of current and blow on a regular basis. They don't perform well
outdoors and can shatter when placed in high temperatures due to its low
thermal stability."

Microwave is not used outdoors or at high temperatures.


From before
According to the label on the back "The input is 1400 watts, but it's a
220 volt device, so that's less than 7amps normally. So, 10, right?
Unless F12 in F12H250 at the top means 12 amps? " And the home.repair
people told me it did, but the web says F means fast-blow.

It's a Crystal, model wp900AP23, but no schematic could I find on the
web and the one taped inside just shows fuse, no details.

 

[Look165]

I've seen no fuse in mine.

Consider the protection is outside and 16A is enough.

micky a Êcrit le 29/03/2019 à 14:14 :

To recap for the scientists: What size fuse to use in a 22V microwave:

In alt.home.repair, on Thu, 28 Mar 2019 19:07:29 -0500, Dean Hoffman
dh0496@windstream.net> wrote:

On 3/28/19 7:00 PM, hubops@ccanoemail.ca wrote:
12a
Okay. I'll look for 12 amps, I'm glad I asked.
But I may have to settle for 10.

Yep - the problem that caused the 12 amp to blow
has surely cleared itself up by now - so a 10 amp is perfect !
.. or not. >> John T.

I suspect that was tongue in cheek. If not, fuses fail just
like everything else involving humans. I've changed a lot of them over the years
without having to do anything else.
LOL. I wasn't living here when it broke; I don't know what they did to
it.

By the same token, I'm leaving and I wanted to either put in the right
fuse or leave a note inside the case for the new owner (my roommate
already bought a replacement and they plan to put this one in the lobby
for someone to take.)

The second store I called had it, even 12 amps, not just 10, but as I
expected, only fast-blow. The original was ceramic.

I thought all ceramic fuses were slo-blo, but this one is embossed
F12H250 and some webpages say that F means fast-blow????
"The types of fuses include long-time-lag or super-time-lag (TT),
fast-acting fuses (FF), quick-blow fuses (F) and slow-blow or time-lag
fuses (T)"
https://www.hunker.com/13418825/difference-between-ceramic-glass-fuses

Nothing I read decribes why a microwave should need ceramic or slow-blo
(in the power part, not the high voltage part).

One page says " Glass has a low rupturing point, such as 15 amperes."

That's fine since it's a 12 amp fuse, and the normal usage is about 7
amps.

" If a high voltage comes down the electrical line, the fuse element
will melt.

Are there really surges that come down the line that increase the
amperage for normally 7 to over 12?

"The tiny glass fuses are great for small items that don't draw a heavy
amount of current and blow on a regular basis. They don't perform well
outdoors and can shatter when placed in high temperatures due to its low
thermal stability."

Microwave is not used outdoors or at high temperatures.


From before
According to the label on the back "The input is 1400 watts, but it's a
220 volt device, so that's less than 7amps normally. So, 10, right?
Unless F12 in F12H250 at the top means 12 amps? " And the home.repair
people told me it did, but the web says F means fast-blow.

It's a Crystal, model wp900AP23, but no schematic could I find on the
web and the one taped inside just shows fuse, no details.