Digest for sci.electronics.repair@googlegroups.com - 7 updates in 2 topics

9:46 AM Penedão 0 comments
jurb6006@gmail.com: Apr 23 12:26AM -0700

I just cleaned a Brother.
 
Has separate ink cartridges, the head stays. It wasn't the head, the tubes were clogged up. The black was actually what was clogged up, the others had air pockets in them. Probably got run too low for too long. I looked around the internet and found out that apparently Windex is safe to use. So I took some tubing, removed the feed (and lost the clip) and blew Windex through the tube. then I fashioned a spring thing to hold what the clip used to hold and let er rip with a bunch of black only cleaning cycles to purge the cleaner and get ink in there.
 
The ink in the black tube actually looked dried out. I guess that;s what happens when there is air in it.
 
It works now. The colors don't come out absolutely perfect on the test page but we'll do a bunch of color printing with the new ink in it and that should take care of it. They are obviously not dried up because they work.
 
My last two jobs, at what they billed my labor you could have bought at least four of these printers with a fresh set of cartridges each, and then some. They would definitely never take another one in once they found out how cheap they are. But I am in frugal mode right now.
Ralph Mowery <rmowery28146@earthlink.net>: Apr 23 10:55AM -0400

In article <0d2f9d3f-3a12-408e-9594-2cad12859c8a@googlegroups.com>,
jurb6006@gmail.com says...
 
> I just cleaned a Brother.
 
> Has separate ink cartridges, the head stays. It wasn't the head, the tubes were clogged up. The black was actually what was clogged up, the others had air pockets in them. Probably got run too low for too long. I looked around the internet and found out that apparently Windex is safe to use. So I took some tubing, removed the
feed (and lost the clip) and blew Windex through the tube. then I fashioned a spring thing to hold what the clip used to hold and let er rip with a bunch of black only cleaning cycles to purge the cleaner and get ink in there.
 
> The ink in the black tube actually looked dried out. I guess that;s what happens when there is air in it.
 
> It works now. The colors don't come out absolutely perfect on the test page but we'll do a bunch of color printing with the new ink in it and that should take care of it. They are obviously not dried up because they work.
 
> My last two jobs, at what they billed my labor you could have bought at least four of these printers with a fresh set of cartridges each, and then some. They would definitely never take another one in once they found out how cheap they are. But I am in frugal mode right now.
 
Unless you have a heavy duty printer, it is often better just to get a
new one. With printers less than $ 70 and some less than $ 50, just get
a new one and the ink cartridges for less than $ 150. A repair bill
will cost a lot and then you still have to pay for the ink.
 
Company my son works for got talked into a deal with Canon for their
printers. It is a large company,but they have 3 men just for office type
printers. Most of the time they just sit around. For what they pay for
that conract, they could probalby buy everyone a new printer every year.
"pfjw@aol.com" <peterwieck33@gmail.com>: Apr 23 08:01AM -0700

We have an Epson eco-tank unit. It reminds us to print something on the first of each month. So far, so good. Not the cheapest printer in the pack, but it meets our modest needs. The double-sided print feature is also appealing.
 
We do about 80 pages per month to various ends.
 
Peter Wieck
Melrose Park, PA
jurb6006@gmail.com: Apr 23 08:43AM -0700

>"Unless you have a heavy duty printer, it is often better just to get a
new one."
 
1. I got time on my hands.
 
2. I am sick of this "You can buy" shit, all of which sends our borrowed money overseas. And if you think YOU don't use credit, the dollars are on credit. Anytime I can keep money from foreigners I think that is good.
 
I do have a LASER printer, but this one avoids a trip to the basement. It's also the only FAX machine in the house and while it would send it wouldn't print so... Also could not print the confirmation of a sent FAX.
 
I am also going through stuff to work on, I got time. I haven't been able to work for awhile so I need to get my legs back so to speak. Next is a microwave bought in 1992. When they were $ 89 this one was $ 150 wholesale. A new one will not outlast it. It has a burned out light, a bad connection, I think to the gate of the triac, and I am going to trow a capacitor in it whether it is good or not. (seems like it used to have more power.
 
New and improved means improved profits for the manufacturer, cheaper to produce and as a result harder to work on usually.
 
>"For what they pay for that conract, they could probalby buy everyone a new printer every year. "
 
Well, a local grocery store has 8 oz. cans of sauce or 20 cents or a 15.5 ox can of he same thing for 69 cents. A bag boy didn't set those prices. Don't expect brains from anyone.
 
And now, if this printer ever needs cleaning agian it will be a 15 minute job.
jurb6006@gmail.com: Apr 23 08:46AM -0700

>"We do about 80 pages per month to various ends. "
 
I do even less than that, except for now because I have a court case and am going pro se. But because I print less I have to buy a more expensive printer - a LASER. I also like that the prints are waterproof, and a few other things proof. Seems like an inkjet print bleeds from looking at it and thinking about water. But get that ink on your hands and...
+++ATH0 <news@ringpiece.local>: Apr 22 04:10PM -0700

On 2018-04-17 07:11, Ragnusen Ultred wrote:
> Am Tue, 17 Apr 2018 13:14:57 +0100, schrieb James Wilkinson Sword:
 
>> A load of shit
 
> Another load of shit
 
 
What a load of shit you tossers spout.
"Jimmy Wilkinson Knife" <nowhere@somewear.co.uk>: Apr 23 12:21AM +0100


>>> A load of shit
 
>> Another load of shit
 
> What a load of shit you tossers spout.
 
What do you expect from someone called "Ragnusen"?
 
--
Worlds most powerful nob enlarger - a space suit with a fly zip
You received this digest because you're subscribed to updates for this group. You can change your settings on the group membership page.
To unsubscribe from this group and stop receiving emails from it send an email to sci.electronics.repair+unsubscribe@googlegroups.com.

Digest for sci.electronics.repair@googlegroups.com - 8 updates in 2 topics

9:40 AM Penedão 0 comments
etpm@whidbey.com: Apr 21 10:31AM -0700

On Sat, 21 Apr 2018 15:13:02 +1200, "~misfit~"
>Electrolube HTC or, for 'cheap jobs' that need a lot of it and have large
>contact areas / raditaors (mostly aluminium LED PCBs to heatsinks), stuff I
>get from AliExpress.
The reason the glass is so flat is because it is floated on molten tin
in order to flatten it. So it should match the curvature of the earth.
Though not flat enough to use as a surface plate for much of the
inspection work I do it is still very flat and plenty good enough to
use with wetordry paper to flatten stuff like the sealing surfaces for
air compressor reed valves.
Eric
Mike S <mscir@yahoo.com>: Apr 21 04:47PM -0700

> use with wetordry paper to flatten stuff like the sealing surfaces for
> air compressor reed valves.
> Eric
 
Interesting. I remember reading that ocean water is higher near
underwater mountain tops due to increased gravitational attraction and
measurable from satellites, I wonder if tanks could be designed with
non-flat bottoms to counteract what you mentioned.
jurb6006@gmail.com: Apr 21 05:19PM -0700

>"Interesting. I remember reading that ocean water is higher near
underwater mountain tops due to increased gravitational attraction and
measurable from satellites,"
 
The would be one hell of a dense mountain to do that, I would think it more likely to be because of a decreased gravitational pull being forced away from the center of mass of the planet, due to its inverse square relationship. But that is not my field of expertise. (is anything ? the more I learn the less I know, if it weren't for learning from mistakes I would be a babbling idiot - NO COMMENTS FROM THE PEANUT GALLERY HERE !)
 
>"I wonder if tanks could be designed with non-flat bottoms to counteract what you mentioned"
 
Pretty sure that would not work because gravity is the leveling force. As such the shape of the bottom should not matter.
 
Perhaps at a high altitude with a very large mass (dense, not voluminous) placed under the center of the tank it could be compensated. But then that makes splitting hairs look like hitting the broad side of a barn with a planet.
jurb6006@gmail.com: Apr 21 05:21PM -0700

Actually, maybe a half spherical or hyperbolic shaped tank bottom would work. However that would take a hell of alot of tin.
Mike S <mscir@yahoo.com>: Apr 21 05:46PM -0700


>> "I wonder if tanks could be designed with non-flat bottoms to counteract what you mentioned"
 
> Pretty sure that would not work because gravity is the leveling force. As such the shape of the bottom should not matter.
 
> Perhaps at a high altitude with a very large mass (dense, not voluminous) placed under the center of the tank it could be compensated. But then that makes splitting hairs look like hitting the broad side of a barn with a planet.
 
I don't know the correct physics, just read a bit...
 
Satellite observations
The alternative is an indirect method that uses satellites fitted with
radar altimeters.
These spacecraft can infer the shape of the ocean bottom from the shape
of the water surface above.
Because water follows gravity, it is pulled into highs above the mass of
tall seamounts, and slumps into depressions over deep trenches.
http://www.bbc.com/news/science-environment-29465446
 
The Hidden Earth: Undersea Mountains by the Thousands
http://www.slate.com/blogs/bad_astronomy/2014/10/07/geography_thousands_of_undersea_mountains_discovered_via_satellite.html
Clifford Heath <no.spam@please.net>: Apr 22 10:00PM +1000

On 22/04/18 10:46, Mike S wrote:
> http://www.bbc.com/news/science-environment-29465446
 
> The Hidden Earth: Undersea Mountains by the Thousands
> http://www.slate.com/blogs/bad_astronomy/2014/10/07/geography_thousands_of_undersea_mountains_discovered_via_satellite.html
 
Makes perfect sense to me. Consider, the material of
the mount must be more dense than water. If its
mechanical strength evaporated it would droop down
to form a level plain. So there's more mass between
the peak and the center of the earth, and more
between mean sea level and the center also. More mass,
more gravity. It'll pull the sea surface towards
itself.
 
Clifford Heath.
Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Apr 21 08:30PM -0400

On 04/16/18 17:10, Mike Coon wrote:
 
>> They not only explode they stink up the whole room.
 
> The best stinky component I remember (from decades ago) was the selenium
> rectifier!
 
Yup. That horrible smell is also horribly toxic.
 
Cheers
 
Phil Hobbs
 
 
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510
 
http://electrooptical.net
http://hobbs-eo.com
Mike Coon <gravity@mjcoon.plus.com>: Apr 22 09:06AM +0100


> Lytics can explode if no such precautions are taken during mfr
> NT
 
Now I have remembered that in 1961 between school and college I had a
holiday job with Radford's in Bristol, UK, who made PA amps for
supermarkets. (Quite a new idea, then, perhaps.) Their snooty designer,
fully suited, came to review the first of his new design off the
production line, and I was one of the erks in attendance. As he bent
over it to inspect our workmanship a large electrolytic exploded and
decorated him with confetti. There were a lot of badly bitten lips and
choked-off splutters...
 
So I am familiar with the danger, after all!
 
Mike.
You received this digest because you're subscribed to updates for this group. You can change your settings on the group membership page.
To unsubscribe from this group and stop receiving emails from it send an email to sci.electronics.repair+unsubscribe@googlegroups.com.

Digest for sci.electronics.repair@googlegroups.com - 5 updates in 1 topic

9:49 AM Penedão 0 comments
dplatt@coop.radagast.org (Dave Platt): Apr 20 10:35AM -0700

In article <c3a729a6-4845-4c00-a524-a88dd8c2ff34@googlegroups.com>,
 
> So conceivably couldn't they just not crank the clock to the max and save power and generate less heat ? Or
>do they already do that ? My laptops have a setting, performance, balanced and battery life. Is that possibly an indirect "underclocking"
>control ? If not, what is it ?
 
Yes, almost certainly it is just that (and perhaps more as well).
 
Most modern CPUs/motherboards/chipsets support multiple CPU clock
rates - the CPU's own internal clock signal is created via a
PLL/multiplier system, based on a slower fixed-rate crystal clock.
The multiplier system is under processor control, so it's possible for
the CPU to switch speeds "on the fly" (with a momentary pause while
the PLL re-locks). I believe this is usually managed via the ACPI
layer in the BIOS/UEFI.
 
At the higher (user-visible) layer, this is usually set up via a
performance setting of the sort you mention. The setting then
controls a set of policies managed by the operating system, which
specify when to change CPU clock speeds (and sometimes voltages as
well) based on your usage patterns.
 
"Battery life" would probably lock the speed at the lowest supported
value, or at least to range of the slower values. "Performance" might
lock it to the highest speed at all times. "Balanced" would either be
a fixed speed in the middle of the range, or a dynamic system which
increases the CPU speed in increments when the CPU is mostly busy, and
reduces it when the CPU is idle more than a certain fraction of the
time.
 
On the Linux laptop I use, I have a choice of several such dynamic
policies... some are more aggressive about increasing CPU speed, some
are more conservative. The CPU speed can be varied over a range of
about 2:1, on a per-core basis (and a core which is currently sitting
idle isn't using much current at any clock speed, although consumption
is less at the lower clock speeds even when idle).
 
>capacitance. As such,lower clock speeds should be quite effective. If they could get it down to the point where no heatsink is needed at all,
>wouldn't there be enough advantage in cost to justify a slightly lower clock speed ? A phone accessing the internet for example, how much does
>that clock speed really mean then ? I am not being sarcastic here, that is a valid question, (I think) how processor intensive is all this ?
 
Depends what you're doing. Just downloading a file is probably not
CPU-expensive. Rendering a web page full of fancy animated graphics
and video, considerably more so. Doing full-screen video may require
little from the CPU, but may push the GPU quite hard (MPEG-4 or
similar video decoding).
 
Phones _tend_ to be designed to optimize battery life, as this is a
key selling point... and so they'll be somewhat more conservative
about speeding up their CPUs.
 
And, phones do have heatsinks. They're called "hands" :-)
Clifford Heath <no.spam@please.net>: Apr 21 08:33AM +1000

>> an equal and opposite increase in clock speeds."
>> I stopped all attempts at overclocking in the Pentium 2 days, but I grasp the concept. However, from what I have gleaned the processor speed is not the end of the world usually. In a PC for example the RAM is slower, the HD slower than that, and so on until we get to the speed of access to data sources, i.e. the internet.
 
> OTOH the CPU does a lot more than the others. Sometimes cpu is the limiting factor, sometimes not. IMLE with clocking it did make a significant difference. I don't bother clocking now, but once it was a deal maker.
 
 
The CPU chip's Front-Side Bus has been the main
choke point for well over a decade. The CPUs
already execute 40 instructions in the time it
takes to fetch one, so faster internal clock
speeds have limited impact.
 
This is why the RISC/CISC wars of the 90s died
out. It's all about bandwidth, not MIPS.
Jeff Liebermann <jeffl@cruzio.com>: Apr 20 06:56PM -0700

On Fri, 20 Apr 2018 07:37:13 -0000 (UTC), gregz <zekor@comcast.net>
wrote:
 
>good to try and achieve. I noticed some power modules were not perfectly
>flat, and I started to sand them on a flat precision table. They were
>pretty far off from flat.
 
Nope. They might be warped on arrival, but are impossible to
straighten without sanding or milling.
 
Back in about 1976, we were having flatness problems with the
transistors used in a linear power supply. There was a large extruded
aluminum heat sink, and either 4 or 8 2N3055 transistors in TO3
packages. The heat sink was milled and quite flat, but the TO3
packages were warped from what I would guess was a worn stamping die.
Some clever person in production decided that the cases could be
straightened most easily by simply tightening the 6-32 screws holding
the devices to the heat sink. After crushing the nylon shoulder
washer, he torqued the hell out of the screw until the head broke off,
and then gave up. The uneven squashing of the silpad insulator showed
that the case was still warped.
 
At that point, someone in production decided that I needed some unpaid
overtime. It was now my project, errr... headache. I put together a
dial indicator and verified that no amount of pressure from 6-32
mounting screws is going to bend the TO3 base when the spot welded lid
was acting as a stiffener. Using a strain gauge, a bar of steel, and
brute force, I determined that the best I can do with trying to
straighten the TO3 packages was to bend ears near the mounting holes,
making the flatness problem even worse. I fixed a few packages by
milling the bottom of the package, but the cost was too high. Cheaper
just to buy new transistors from a different vendor that weren't
warped.
 
The only good thing to come out of this waste of time was a fixture
that I threw together to measure the flatness of the TO3 and later RF
power transistor packages. It saved having the same problem repeat
itself in later years.
 
--
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
"~misfit~" <shaun.at.pukekohe@gmail.com>: Apr 21 03:13PM +1200

> stuff they make the heatsinks out of is very soft and the screws
> might strip. The main thing is not to let it come up or move. If it
> is done right they are usually stuck pretty good though.
 
I've pressed very hard on some components, watched the compound come out all
around then, on relasing the pressure to 'fastener pressure' have seen some
of the ooze suck back in and sometmes air suck back in. Granted these
weren't on ideal surfaces but since then, on those types of interfaces I let
the fastener do the squeezing.
 
> unfortunately lapping is simply impossible on most. I also agree with
> Jeff Leiberman's caveat about making the surface concave. If you do
> that it could be worse than not lapping at all.
 
I have variously sized bits of glass that I use as backing for the wet'n'dry
sandpaper that I use to ensure relative flatness. The glass isn't as flat as
gauge blocks but it's sufficient.
 
> caulking gun full of compound like this one place I worked. Makes it
> easier to apply and I would never run out. They did but it took years
> even with a bunch of techs working.
 
For laptops, desktops and critcal ICs I use Arctic Silver. I bought a 'PC
builders' size syringe of it. For less critical stuff I use either
Electrolube HTC or, for 'cheap jobs' that need a lot of it and have large
contact areas / raditaors (mostly aluminium LED PCBs to heatsinks), stuff I
get from AliExpress.
--
Shaun.
 
"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)
 
"~misfit~" <shaun.at.pukekohe@gmail.com>: Apr 21 03:21PM +1200

>> If you need electrical insulation, petroleum jelly is probably
>> better. The main objective is to fill the air gaps.
 
> Petroleum jelly melts & runs.
 
TMI.
--
Shaun.
 
"Humans will have advanced a long, long way when religious belief has a cozy
little classification in the DSM*."
David Melville (in r.a.s.f1)
(*Diagnostic and Statistical Manual of Mental Disorders)
You received this digest because you're subscribed to updates for this group. You can change your settings on the group membership page.
To unsubscribe from this group and stop receiving emails from it send an email to sci.electronics.repair+unsubscribe@googlegroups.com.
Subscribe to: Posts (Atom)