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Or blow a fuse or the shunt in your ammeter. An ideal ammeter has zero"Dave Plowman (News)" <dave@davenoise.co.uk> wrote in message
news:4f929585a6dave@davenoise.co.uk...
In article <4ppOj.4843$iK6.2204@nlpi069.nbdc.sbc.com>,
Who Me? <hitchhiker@dont.panic> wrote:
I'd be utterly amazed if any charger said to have a maximum output of
1.5 amps managed 4-6. The reverse I would believe...
That IS somewhat of a stretch but not totally impossible. The max.
current output shown is at the rated voltage. So, for instance, a
device rated at 1.5A, 12V should supply 12V up to the rated current load
of 1.5A (or somewhere close). If you continue to increase the load,
the amperage may increase beyond 1.5A......as the supplied voltage
drops below 12V.
It would be a strange power supply that allowed that. Although it might be
possible with different tappings on a transformer.
If you put the ammeter straight across it, shorting the output of the
charger, it would not surprise me at all if it managed 4-6A, obviously this
is not a useful measurement and it wouldn't take long for it to overheat
though.
But only if the meter is not capable of measuring the absolute max currentIn article <r1rOj.52$NK1.25@trndny05>,
"James Sweet" <jamessweet@hotmail.com> wrote:
"Dave Plowman (News)" <dave@davenoise.co.uk> wrote in message
news:4f929585a6dave@davenoise.co.uk...
In article <4ppOj.4843$iK6.2204@nlpi069.nbdc.sbc.com>,
Who Me? <hitchhiker@dont.panic> wrote:
I'd be utterly amazed if any charger said to have a maximum output
of
1.5 amps managed 4-6. The reverse I would believe...
That IS somewhat of a stretch but not totally impossible. The max.
current output shown is at the rated voltage. So, for instance, a
device rated at 1.5A, 12V should supply 12V up to the rated current
load
of 1.5A (or somewhere close). If you continue to increase the load,
the amperage may increase beyond 1.5A......as the supplied voltage
drops below 12V.
It would be a strange power supply that allowed that. Although it might
be
possible with different tappings on a transformer.
If you put the ammeter straight across it, shorting the output of the
charger, it would not surprise me at all if it managed 4-6A, obviously
this
is not a useful measurement and it wouldn't take long for it to overheat
though.
Or blow a fuse or the shunt in your ammeter. An ideal ammeter has zero
ohms across its test leads.
Yes, you're right... I should have saidOn Apr 19, 5:04 pm, "DaveM" <masondg4...@comcast99.net> wrote:
In your tape circuit, the big clue to the problem is lack of any voltage at
the
collector of Q205. Q205 must be turned on, at least partially, in order for
any
voltage to appear at its collector (which is showing no voltage). It is the
only path that can supply the current to Q203 is through the E-C circuit of
Q205. If Q205's B-E is properly forward biased, current should flow through
the
C-E circuit.
Could you repeat this part, please?
There is no Q203 in this circuit.
Thanks for your help!
Yes, you're right... I should have saidOn Apr 19, 5:04 pm, "DaveM" <masondg4...@comcast99.net> wrote:
In your tape circuit, the big clue to the problem is lack of any voltage at
the
collector of Q205. Q205 must be turned on, at least partially, in order for
any
voltage to appear at its collector (which is showing no voltage). It is the
only path that can supply the current to Q203 is through the E-C circuit of
Q205. If Q205's B-E is properly forward biased, current should flow through
the
C-E circuit.
Could you repeat this part, please?
There is no Q203 in this circuit.
Thanks for your help!
"Gareth Magennis" <sound.service@btconnect.com> writes:
"Bennett Price" <""bjpriceNOSPAM\"@NOSPAMcal berkeley.edu"> wrote in
message
news:RFqOj.3153$h75.936@newssvr27.news.prodigy.net...
I've got a small 12V DC .9 Watt 'muffin' fan (1.75"x1.75"x3/8").
It was the cooler for a video card's processor chip and was
frozen up.
I put a drop of oil into its sleeve bearing and it now runs
reliably - almost. It will start every time as long as it is
not oriented with the open 'face' down. (The open face is the
side in which you can see the bearing). If the open bearing is
down, it sometimes starts and sometimes needs a slight nudge to
get it going.
What's going on? How come? TIA
Presumably because the bearings are worn out. Get another one.
I've disassembled these, cleaned, and relubed with decent success.
But a new fan is not expensive.
"Gareth Magennis" <sound.service@btconnect.com> writes:
"Bennett Price" <""bjpriceNOSPAM\"@NOSPAMcal berkeley.edu"> wrote in
message
news:RFqOj.3153$h75.936@newssvr27.news.prodigy.net...
I've got a small 12V DC .9 Watt 'muffin' fan (1.75"x1.75"x3/8").
It was the cooler for a video card's processor chip and was
frozen up.
I put a drop of oil into its sleeve bearing and it now runs
reliably - almost. It will start every time as long as it is
not oriented with the open 'face' down. (The open face is the
side in which you can see the bearing). If the open bearing is
down, it sometimes starts and sometimes needs a slight nudge to
get it going.
What's going on? How come? TIA
Presumably because the bearings are worn out. Get another one.
I've disassembled these, cleaned, and relubed with decent success.
But a new fan is not expensive.
I'd be looking for a latch. Once released, you should be able to pullI'm trying to repair a balky piece of ham gear... trying to check some
suspect solder connections on the back side of a board... can't figure
out how to get the board loose so I can access the back side!
Problem is those little interboard connectors. Rectangular white plastic
connectors on the board, wires crimped to pins that insert in brown
plastic shell that plugs into the white shell on the board.
- Grab the wire & pull? I've made that mistake in the past with other
gear... managed to pull the wire out of the pin, leaving the shell firmly
in place with the rest of the wires.
- Grab the shell with a long-nosed pliers & pull? Doesn't work any
better. There isn't enough exposed plastic shell to get a good hold; the
pliers slip & threaten to grab the wire & yank it out of the pin. (as
above) (luckily I haven't actually yanked a wire loose this way but
that's only due to sheer luck.)
- Use a small flat-blade screwdriver to pry up on the two ends of the
plastic shell? The shell seems to be so firmly seated that, rather than
prying the shell out of the board end of the connector, I'm prying the
entire connector off the board. (I'm stopping before using anywhere near
that much force!)
- Tilt the board back with the wires still connected? Would love to do
that but the wire in question is way too short.
The problem seems to be that the plastic shell on the cable mates so
snugly with the plastic shell on the board that the amount of force
necessary to separate them exceeds the amount necessary to pull the wires
loose or to pull the connector off the board.
What's the trick to getting these disconnected without destroying anything?
Please don't tell me some manufacturers are gluing these together after
assembly?! (though at this point I'd believe it, despite not seeing any
glue)
I'd be looking for a latch. Once released, you should be able to pullI'm trying to repair a balky piece of ham gear... trying to check some
suspect solder connections on the back side of a board... can't figure
out how to get the board loose so I can access the back side!
Problem is those little interboard connectors. Rectangular white plastic
connectors on the board, wires crimped to pins that insert in brown
plastic shell that plugs into the white shell on the board.
- Grab the wire & pull? I've made that mistake in the past with other
gear... managed to pull the wire out of the pin, leaving the shell firmly
in place with the rest of the wires.
- Grab the shell with a long-nosed pliers & pull? Doesn't work any
better. There isn't enough exposed plastic shell to get a good hold; the
pliers slip & threaten to grab the wire & yank it out of the pin. (as
above) (luckily I haven't actually yanked a wire loose this way but
that's only due to sheer luck.)
- Use a small flat-blade screwdriver to pry up on the two ends of the
plastic shell? The shell seems to be so firmly seated that, rather than
prying the shell out of the board end of the connector, I'm prying the
entire connector off the board. (I'm stopping before using anywhere near
that much force!)
- Tilt the board back with the wires still connected? Would love to do
that but the wire in question is way too short.
The problem seems to be that the plastic shell on the cable mates so
snugly with the plastic shell on the board that the amount of force
necessary to separate them exceeds the amount necessary to pull the wires
loose or to pull the connector off the board.
What's the trick to getting these disconnected without destroying anything?
Please don't tell me some manufacturers are gluing these together after
assembly?! (though at this point I'd believe it, despite not seeing any
glue)
Hi,
I've moved to N America from Europe and I'm changing some power connector.
My Question now is, when I look from the front on the connector, Ground on
the bottom, is the phase on the left or on the right? I unfortunately
don't
have a phase tester handy.
Thanks,
Ron
--
chEErs roN
Try steel toe caps.On Sat, 19 Apr 2008 15:34:16 -0700
Aratzio <a6ahlyv02@sneakemail.com> wrote:
On Sat, 19 Apr 2008 16:09:53 -0500, in the land of alt.usenet.kooks,
snuhwolf@netscape.net (§ńühw¤Łf) got double secret probation for
writing:
Aratzio <a6ahlyv02@sneakemail.com> clouded the waters of pure
thought with:
On Sat, 19 Apr 2008 09:01:56 -0700, in the land of
alt.usenet.kooks, §ńühw¤Łf <snuhwolf@netscape.net> got double
secret probation for writing:
On Sat, 19 Apr 2008 13:35:53 +1000
"Kadaitcha Man" <nospam.nospam.nospam@gmail.com> wrote:
"Aratzio" <a6ahlyv02@sneakemail.com> wrote in message
news:9opi0456deigk7ihd4bq4mq3u9mar9tha3@4ax.com...
On Sat, 19 Apr 2008 13:26:03 +1000, in the land of
alt.usenet.kooks, "Kadaitcha Man"
nospam.nospam.nospam@gmail.com> got double secret probation
for writing:
"Butch Haynes" <butch@huntsville> wrote in message
news:zbmdnUfjYIjDTZXVnZ2dnUVZ_gWdnZ2d@comcast.com...
radiant_x@outgun.com> wrote in message
news:293e3140-e027-496c-89d8-27906e8991f7@t54g2000hsg.googlegroups.com...
I recently installed a DVD drive into my PC. (2 days ago.)
Since then, I get spontaneous power loss periodically -
sometimes seconds after booting, other times after hours of
operation. I've tried replacing the power supply, and I've
tried removing all my hardware (other than RAM), so I'm
thinking it must be motherboard related.
Unplug/replug all power and data connections. That way, the
errant loose one will be fixed and your problem will be
resolved.
BWAHAHAHAHAHAHAHAHAHAHAHAHA!
Tech support by feng shui.
"I've tried removing all my hardware(other than RAM)"
Do none of them understand what that entails?
None of them understand anything.
I go toetally on into-ition.
Just do what feels good for a few hours...take out a few
cables...fondle them...blow out the dust bunnies...listen to the
Grateful Dead live at Winterland for inspiration. Drink another
beer...
Change a bunch of jumpers on the Mobo at random.
Leave shit scattered around on yer workbench and wander away.
Watch cartoons for another hour...
Come back and put it back together.
Holy Shit! Now it works.
Thats how I do it anyway.
FYI
HTH
Dunno why you geeks muck about with all that crap.
I take em out to the back 40, prop em against the side of the gully
and show them my Springfield 30-06.
BLINK
BLINK
OMG! I would never shoot a poor defenceless computer!
They always work after that.
I assume you miss...
Works good with the employees, wife and kids too.
Note to self: dont work for 'Ratz.
Never had need to actually fire the damn thing.
Interesting. So you say that pc's respond to threats of annihilation?
I've got a sledge hammer laying about...
Will it solve my booting problems?
The heads on modern HD's automatically retract when power is removed,On Apr 17, 8:51 pm, cuhu...@webtv.net wrote:
Your DVD drive could be defective.So could that second power drive
tone of the worst things to do with a computer is to physically
unplug that computer without properly shutting the computer down first.
cuhulin
I agree. Shutting a computer down by simply unplugging it (a method
I call "brute force") rather than using the correct shutdown procedure
can and often does corrupt the operating system, requiring that the
entire OS be reinstalled--not to mention all your application programs
you may have installed at the time. Most of the time the computer will
go into safe mode if it is shut down other than by the recommended
procedure, but I wouldn't count on it. I don't even remember how many
times my first Windows computer (running Win95) crashed and corrupted
the operating system when I tried to shut down the system with the
brute force technique. (I don't do that anymore with my current
Win98SE system unless I have to, say if the computer freezes and
absolutely cannot be shut down normally; live and learn.) Another
problem with shutting down simply by pulling the plug is that the hard
drive may have errors on it when the system is restarted; many if not
most Windows computers are set up by default to scan the hard disk as
soon as the system boots after a crash. The system can be set to
repair automatically any errors thus found.
Still another potentially fatal (for the computer) problem created by
the act of shutting down without following the correct procedure is
that the read/write heads of the hard disk will literally crash into
the disk, again with the potential for disk errors when the system
is rebooted. These crashes will eventually ruin your hard drive, so it
is best to avoid them if possible. Occasional disk crashes are
inevitable (power outages, for example), but here I am speaking of
unnecessary hard disk crashes caused by incorrect shutdowns; for
maximum trouble-free life of your hard disk, please, for gosh sakes
use the Windows-recommended shutdown method. This can be accessed
directly from the Start menu by clicking on "Shut Down" and selecting
the option of the same name from the menu which appears, or by doing
the so-called "three-finger salute", i.e. pressing Ctrl+Alt+Delete
while the computer is powered up.
Jeff Strieble, WB8NHV
Fairport Harbor, Ohio USA
That's an expensive way - although of course a good one. For many years IDo you have an oscilloscope?? If you do, it is a simple matter of
tracking the signal on the good side and comparing it to the "lack of
signal" in the bad side, stage by stage.
"Sam Goldwasser" <sam@minus.seas.upenn.edu> wrote in message
news:6w4p9xidem.fsf@minus.seas.upenn.edu...
"Gareth Magennis" <sound.service@btconnect.com> writes:
"Bennett Price" <""bjpriceNOSPAM\"@NOSPAMcal berkeley.edu"> wrote in
message
news:RFqOj.3153$h75.936@newssvr27.news.prodigy.net...
I've got a small 12V DC .9 Watt 'muffin' fan (1.75"x1.75"x3/8").
It was the cooler for a video card's processor chip and was
frozen up.
I put a drop of oil into its sleeve bearing and it now runs
reliably - almost. It will start every time as long as it is
not oriented with the open 'face' down. (The open face is the
side in which you can see the bearing). If the open bearing is
down, it sometimes starts and sometimes needs a slight nudge to
get it going.
What's going on? How come? TIA
Presumably because the bearings are worn out. Get another one.
I've disassembled these, cleaned, and relubed with decent success.
But a new fan is not expensive.
Yes, not nearly as expensive as the possible damage caused by a stalled
worn out fan that soemone tried to bodge back to working condition instead
of replacing it. I'm thinking Power Amps, computer chips, or any gear
that someone has paid you to fix properly.
Gareth.
Is the buzz affected by the volume control ?On Apr 20, 5:15 am, Peter Dettmann <pe...@aardvark.net.au> wrote:
On Sat, 19 Apr 2008 19:42:23 -0700 (PDT), EricM <ew_m...@hotmail.com
wrote:
Forgot to mention that the 'buzzing' only starts after the relay
closes - so more evidence that it's either the 80/450's in the PS, or
possibly a problem somewhere around the voltage divider/0A2/6DR7
portion of the circuit that is fed from the 600V terminal in the amp.
Not possible that it is the relay itself that is mechanically buzzing
perhaps?
Peter
The relay itself isn't making any noise; it did 'buzz' a little
before the fuse blew prior to fixing that problem, but it's a 60hz
noise in the speaker now. Suspect the PS since most everything in the
amp that could leak 60hz has been replaced.
Is the buzz affected by the volume control ?On Apr 20, 5:15 am, Peter Dettmann <pe...@aardvark.net.au> wrote:
On Sat, 19 Apr 2008 19:42:23 -0700 (PDT), EricM <ew_m...@hotmail.com
wrote:
Forgot to mention that the 'buzzing' only starts after the relay
closes - so more evidence that it's either the 80/450's in the PS, or
possibly a problem somewhere around the voltage divider/0A2/6DR7
portion of the circuit that is fed from the 600V terminal in the amp.
Not possible that it is the relay itself that is mechanically buzzing
perhaps?
Peter
The relay itself isn't making any noise; it did 'buzz' a little
before the fuse blew prior to fixing that problem, but it's a 60hz
noise in the speaker now. Suspect the PS since most everything in the
amp that could leak 60hz has been replaced.
There are anti-vibration connectors in which pulling the wires makes theI'm trying to repair a balky piece of ham gear... trying to check some
suspect solder connections on the back side of a board... can't figure
out how to get the board loose so I can access the back side!
Problem is those little interboard connectors. Rectangular white plastic
connectors on the board, wires crimped to pins that insert in brown
plastic shell that plugs into the white shell on the board.
- Grab the wire & pull? I've made that mistake in the past with other
gear... managed to pull the wire out of the pin, leaving the shell firmly
in place with the rest of the wires.
- Grab the shell with a long-nosed pliers & pull? Doesn't work any
better. There isn't enough exposed plastic shell to get a good hold; the
pliers slip & threaten to grab the wire & yank it out of the pin. (as
above) (luckily I haven't actually yanked a wire loose this way but
that's only due to sheer luck.
There are anti-vibration connectors in which pulling the wires makes theI'm trying to repair a balky piece of ham gear... trying to check some
suspect solder connections on the back side of a board... can't figure
out how to get the board loose so I can access the back side!
Problem is those little interboard connectors. Rectangular white plastic
connectors on the board, wires crimped to pins that insert in brown
plastic shell that plugs into the white shell on the board.
- Grab the wire & pull? I've made that mistake in the past with other
gear... managed to pull the wire out of the pin, leaving the shell firmly
in place with the rest of the wires.
- Grab the shell with a long-nosed pliers & pull? Doesn't work any
better. There isn't enough exposed plastic shell to get a good hold; the
pliers slip & threaten to grab the wire & yank it out of the pin. (as
above) (luckily I haven't actually yanked a wire loose this way but
that's only due to sheer luck.
use a pair of pliers that is wide enough to get the width of the connector.On Sun, 20 Apr 2008 16:19:10 -0400, Meat Plow wrote:
On Sun, 20 Apr 2008 10:05:17 -0500, Doug Smith W9WI wrote:
I'm trying to repair a balky piece of ham gear... trying to check some
suspect solder connections on the back side of a board... can't figure
out how to get the board loose so I can access the back side
How about taking a picture and uploading to tinypic.com then posting the
link so I can have a look. I'm going on my 3rd decade of being a ham and
I've done a lot of repair. I think I know what you're trying to do but
would like to see before I advise.
http://www.w9wi.com/ham/ft1000mp_local_unit.JPG
A bit fuzzy but I think it's clear enough to show what kind of connector
I'm talking about.
I've seen these in Panasonic professional video gear as well but luckily
have never had to disassemble the video stuff.