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Phil Hobbs
Guest

Thu Jan 10, 2019 5:45 pm   



On 1/10/19 10:37 AM, Ralph Mowery wrote:
Quote:
In article <312172279568800599.965334zekor-comcast.net_at_news.eternal-
september.org>, zekor_at_comcast.net says...

Don't use rubbing alcohol, it contains oil. Vodka is fine.
Clean the pinch wheels as well. All must be bone dry before
putting a tape in.

The heads are metal. No worries about hardening. Who told you
there was oil in rubbing alcohol? It's alcohol and water.
Period.


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.



Rubbing alcohol seems to be a gernetic term by many.

One form is about 70% alcohol and some oils and water.

You can buy some that is about 90% alcohol and 10 % water with no
other oils in it. I have some here labled 91 % and some labled 99%.
They are isoprople alcohol and not labled rubbing alcohol. Alcohol
absorbs water from the atmosphere so before long the 99% will be much
less if open to the air.

Xylene was used at one time to clean the tape machinery. I am not
sure if it is in the stores any more or not.


Some rubbing alcohol is 80% isopropyl and 20% water. That has very
different properties, and will craze acrylics instantaneously. It also
leaves residues that cause enormous amounts of 1/f noise in front end
circuits.

Everclear is much better controlled.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

Fox's Mercantile
Guest

Thu Jan 10, 2019 5:45 pm   



On 1/10/19 9:37 AM, Ralph Mowery wrote:
Quote:
Rubbing alcohol seems to be a gernetic term by many.

One form is about 70% alcohol and some oils and water.


Or you can just buy Denatured alcohol.

Quote:
Xylene was used at one time to clean the tape machinery. I am not sure
if it is in the stores any more or not.


It is available in the paint section.


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

pfjw@aol.com
Guest

Thu Jan 10, 2019 9:45 pm   



Some "Stuff":

Acetone (C3H6O) will attack spolyester resin, many two-part epoxies, ABS plastics, polystyrene, some forms of nylon, lacquer, shellac, unstabilzed celluloid and superglue.

Denatured Alcohol (C2H5OH)is ETHANOL with some other ingredient added to render it unfit for consumption. Typically that "other" is wood alcohol/methanol.

"Rubbing Alcohol" (C3H7OH) is, typically some mixture to include isopropyl alcohol, water and any number of other ingredients, including scents and lubricants.

"Wood Alcohol/Methanol/Stove Fuel" CH3OH) will attack a range of plastics.

https://www.plasticsintl.com/chemical-resistance-chart

A few actual facts do help speed the discussion along. Not to be snarky even a little bit, as I was somewhat surprised by the sensitivities of some things on the list.

Peter Wieck
Melrose Park, PA

Dave Platt
Guest

Thu Jan 10, 2019 9:45 pm   



In article <5f4955a0-fad8-4e2a-b6d7-8ab62e8f6f54_at_googlegroups.com>,
<tabbypurr_at_gmail.com> wrote:
Quote:
On Thursday, 10 January 2019 04:12:57 UTC, The Real Bev wrote:

The heads are metal. No worries about hardening. Who told you there
was oil in rubbing alcohol? It's alcohol and water. Period.

I forget the official standard for it, but it contains rather more than water & alcohol. Looked it up last year.


"Rubbing alcohol" is addressed by several different USP standards.

"Isopropyl Rubbing Alcohol USP" is defined as 70% isopropyl alcohol
(plus or minus a couple of percent) by volume, the remainder
"water, with or without suitable stabilizers, perfume oils, and color
additives certified by the FDA for use in drugs." So, even drugstore
isopropyl alcohol can have components other than alcohol and water.

"Rubbing Alcohol USP" (without the word "isopropyl") is ethanol,
water, denaturants (e.g. sucrose octaacetate or denatonium benzoate),
"with or without color additives, and perfume oils."

Some commercial rubbing alcohol used to contain lanolin, to help keep
the skin from drying out; I don't know if any still does.

If you don't see the term "USP" on the label, then whatever you're
buying may not comply with the USP standards I mentioned.

Outside the US things are even more complex; British "surgical
spirit" is methylated spirit (ethanol denatured with methanol),
castor oil, diethyl phthalate, and methyl salicylate ("wintergreen
oil").

(Relevant information cribbed from the Wikipedia article on rubbing
alcohol, and the newdruginfo.com links which cite the USP
definitions).

For electronics cleaning purposes such as tape-deck heads, I prefer to
buy technical-grade isopropyl alcohol. My local Frys carries the
Puretronics brand ($9/quart).

pfjw@aol.com
Guest

Thu Jan 10, 2019 9:45 pm   



Adding to Dave's post - a bit of history:


"In 1906, President Theodore Roosevelt signed the Pure Food and Drug Act into law. The law elevated the public health role of the United States Pharmacopeia because it defined a drug as “all medicines and preparations recognized in the United States Pharmacopeia (USP) or National Formulary (NF),” and defined adulterated drugs as those referenced in the USP and NF but differing from “the standard of strength, quality, or purity” specified in the two compendia. The practice of labeling medicines with the letters “U.S.P.” or “USP” became more prevalent. In 1938, the Food, Drug and Cosmetic Act reaffirmed the role of the pharmacopeia and expanded its role to include USP standards for labeling and packaging. "

Peter Wieck
Melrose Park, PA


Guest

Thu Jan 10, 2019 10:45 pm   



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

Quote:
The Real Bev <bashley101_at_gmail.com> wrote:
On 01/09/2019 11:03 AM, tabbypurr_at_gmail.com wrote:
On Wednesday, 9 January 2019 16:12:46 UTC, Terry Schwartz wrote:
On Wednesday, January 9, 2019 at 10:07:57 AM UTC-6,
wri...@gmail.com wrote:
On Wednesday, August 2, 2000 at 3:00:00 AM UTC-4, GHilgenber
wrote:

I have a ford ranger and the cassette player has a lot of
static the radio plays fine.I have demagnetizer and cleaning
tapes I was thinking of using acetone on the heads?

Use a cleaning tape or the like . Chemicals and liquids can harm
rollers and other plastic / rubber parts . Alcohol will dry out
the oils in plastics and rubber , causing them to harden .
Acetone will tend to dissolve these materials .

All those materials are 19 years older than when this topic was
initiated.... So yeah, I bet they're dried out.

cleaning tapes are almost hopeless anyway. Wet cleaning is the only
effective option.

Don't use rubbing alcohol, it contains oil. Vodka is fine. Clean the
pinch wheels as well. All must be bone dry before putting a tape in.

The heads are metal. No worries about hardening. Who told you there was
oil in rubbing alcohol? It's alcohol and water. Period.


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


I have used isopropyl alcohol all my long life for audio and video
heads. Works well.....

Acetone is very harsh and will melt plastic and remove paint. I will not
use it for this....


Guest

Fri Jan 11, 2019 5:45 am   



On Thursday, 10 January 2019 20:08:06 UTC, Dave Platt wrote:
Quote:
In article <5f4955a0-fad8-4e2a-b6d7-8ab62e8f6f54_at_googlegroups.com>,
tabbypurr> wrote:
On Thursday, 10 January 2019 04:12:57 UTC, The Real Bev wrote:

The heads are metal. No worries about hardening. Who told you there
was oil in rubbing alcohol? It's alcohol and water. Period.

I forget the official standard for it, but it contains rather more than water & alcohol. Looked it up last year.

"Rubbing alcohol" is addressed by several different USP standards.

"Isopropyl Rubbing Alcohol USP" is defined as 70% isopropyl alcohol
(plus or minus a couple of percent) by volume, the remainder
"water, with or without suitable stabilizers, perfume oils, and color
additives certified by the FDA for use in drugs." So, even drugstore
isopropyl alcohol can have components other than alcohol and water.

"Rubbing Alcohol USP" (without the word "isopropyl") is ethanol,
water, denaturants (e.g. sucrose octaacetate or denatonium benzoate),
"with or without color additives, and perfume oils."

Some commercial rubbing alcohol used to contain lanolin, to help keep
the skin from drying out; I don't know if any still does.

If you don't see the term "USP" on the label, then whatever you're
buying may not comply with the USP standards I mentioned.

Outside the US things are even more complex; British "surgical
spirit" is methylated spirit (ethanol denatured with methanol),
castor oil, diethyl phthalate, and methyl salicylate ("wintergreen
oil").

(Relevant information cribbed from the Wikipedia article on rubbing
alcohol, and the newdruginfo.com links which cite the USP
definitions).

For electronics cleaning purposes such as tape-deck heads, I prefer to
buy technical-grade isopropyl alcohol. My local Frys carries the
Puretronics brand ($9/quart).


We generally use BP & BSes rather than USP. So the answer depends to some extent on where the enquirer is.


NT

Jeff Liebermann
Guest

Fri Jan 11, 2019 8:45 pm   



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

Quote:
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


Perhaps it would be interesting to see what's in a commercial tape
head cleaner?

GC Electronics Magnetic Head Cleaner
Kinda looks like alcohol (ethanol) is safe.
<http://www.gcelectronics.com/order/msds/116.pdf>
Ethanol 86.8%
Methanol 4.5%
Acetic Acid Ethyl Ester 1.1%
2-Pentanone, 4-Methyl- 1.0%
Solvent Naphtha 0.4%
(Petroleum), Light Aliph.
Hexane 0.4%
2-Propanol,2-Methyl- 0.11%
Benzene, Methy- 0.05%
Cyclohexane 0.001%
Other 5.7%

MG Chemicals 407c Audio/video head cleaner
<https://www.mgchemicals.com/products/cleaning-products-for-electronics/cleaners/specialty-cleaners/audiovideo-head-cleaner-407c>
It says "Safe on Plastics".
The composition is somewhat different from the GC head cleaner.
<https://www.mgchemicals.com/downloads/msds/01%20English%20Can-USA%20SDS/sds-407c-l.pdf>
67-63-0 propan-2-ol (IPA) 50%
107-83-5 methyl-2-pentane 15-25%
96-14-0 methyl-3-pentane 5-10%
79-29-8 dimethyl-2,3-butane 5-10%
75-83-2 dimethyl-2,2-butane 3-7%
110-54-3 n-hexane 1-2%

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

Jeff Liebermann
Guest

Fri Jan 11, 2019 8:45 pm   



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

Quote:
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_at_cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558


Guest

Mon Jan 14, 2019 4:45 pm   



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

Quote:
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
Guest

Mon Jan 14, 2019 4:45 pm   



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


Guest

Mon Jan 14, 2019 5:45 pm   



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

Mon Jan 14, 2019 6:45 pm   



On 1/14/19 10:03 AM, tabbypurr_at_gmail.com wrote:
Quote:
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
Guest

Mon Jan 14, 2019 7:45 pm   



On Mon, 14 Jan 2019 07:02:04 -0800 (PST), bruce2bowser_at_gmail.com
wrote:

Quote:
Suffice it to say that using a substance for a purpose not mentioned
on the containers label just isnt 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_at_cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558


Guest

Mon Jan 14, 2019 8:45 pm   



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

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