T
ThePetPage
Guest
And even when they are available, they don't know anything 'bout electronics! I
won't go back. Also, All Electronics Corp is pretty good with parts.
John
won't go back. Also, All Electronics Corp is pretty good with parts.
John
J
John Halley
Guest
My personal experience with Digikey:
I was the official Parts Dude at a well-known company what makes door
security access thingies.
Surface-mount items mostly, but when I wanted it quick, it was Digi-Key.
I would get parts orders in at 4:30 Post Meridian Denver time and have the
merchandise by 10:30 Ante Meridian by FedEx the very next day.
Not bad, I think...
"JS" <JS@huh.wha> wrote in message
news:Xns95628703F997DQ1V66HO78NX3AGH5MJX@127.0.0.1...
| "John Halley" <comet@dimensional.com> wrote in
| news:41434434$1_3@omega.dimensional.com:
|
| > It was overwhelming. There was nothing you couldn't find!
| > I guess I'll just have to start an account with Digikey or Newark or
| > Mouser. --- Heavy sigh...---
| >
|
| Digikey is highly regarded round these parts.
I was the official Parts Dude at a well-known company what makes door
security access thingies.
Surface-mount items mostly, but when I wanted it quick, it was Digi-Key.
I would get parts orders in at 4:30 Post Meridian Denver time and have the
merchandise by 10:30 Ante Meridian by FedEx the very next day.
Not bad, I think...
"JS" <JS@huh.wha> wrote in message
news:Xns95628703F997DQ1V66HO78NX3AGH5MJX@127.0.0.1...
| "John Halley" <comet@dimensional.com> wrote in
| news:41434434$1_3@omega.dimensional.com:
|
| > It was overwhelming. There was nothing you couldn't find!
| > I guess I'll just have to start an account with Digikey or Newark or
| > Mouser. --- Heavy sigh...---
| >
|
| Digikey is highly regarded round these parts.
W
Watson A.Name - \"Watt Su
Guest
"Winfield Hill" <Winfield_member@newsguy.com> wrote in message
news:ci7har02408@drn.newsguy.com...
over, and ruining the insulation properties? I'd guess he has to wear
gloves.
I used an open gate of a 2N7000 FET to probe for leakage. I found that
paper on a humid day works almost like the carbon element from a
potentiometer. I could probe from the negative to positive, and the
closer I got to the positive, the higher the FET current. It's kind of
amazing, when one thinks about it, but all this 'electron movement' is
going on between PCB tracks, and between wires in a bundle, etc. We
just don't kotice it because all the other much higher currents
overwhelm the leakages.
I was reading that they are having problems with the nanometer
geometries of the latest chip fabrications. The electrons get so leaky
that it's becoming a problem telling the signals from the leakage.
news:ci7har02408@drn.newsguy.com...
How does he remove them without getting his sweaty fingerprints all
over, and ruining the insulation properties? I'd guess he has to wear
gloves.
I used an open gate of a 2N7000 FET to probe for leakage. I found that
paper on a humid day works almost like the carbon element from a
potentiometer. I could probe from the negative to positive, and the
closer I got to the positive, the higher the FET current. It's kind of
amazing, when one thinks about it, but all this 'electron movement' is
going on between PCB tracks, and between wires in a bundle, etc. We
just don't kotice it because all the other much higher currents
overwhelm the leakages.
I was reading that they are having problems with the nanometer
geometries of the latest chip fabrications. The electrons get so leaky
that it's becoming a problem telling the signals from the leakage.
W
Watson A.Name - \"Watt Su
Guest
"free stuff guy" <squirrel.hunter@gmail.com> wrote in message
news:ebb9af66.0409151647.74be8d94@posting.google.com...
SPAMMER reported to marketing@gratisnetwork.com
news:ebb9af66.0409151647.74be8d94@posting.google.com...
SPAMMER reported to marketing@gratisnetwork.com
W
Winfield Hill
Guest
Watson A.Name - \"Watt Sun, the Dark Remover\" wrote...
tubes. But it's trivial to degrease items after handling them.
a humid day? It can get so wet you can't write on it with a pencil!
these old beauties. But even without them it's not too hard to make
fixed-range pA and fA sensitivity electronics, by using "in-the-air"
wiring, soldering items together suspended in air. For example, the
inverting input of a cmos opamp can be bent out from the rest, and
not put in a socket or soldered to the printed circuit board.
--
Thanks,
- Win
(email: use hill_at_rowland-dotties-org for now)
I had him remove intact the amplifier assembly that contains the
tubes. But it's trivial to degrease items after handling them.
Yes, paper, absolutely. Ever notice how much water it can absorb on
a humid day? It can get so wet you can't write on it with a pencil!
That's why I like extracting the teflon-terminal switches, etc., from
these old beauties. But even without them it's not too hard to make
fixed-range pA and fA sensitivity electronics, by using "in-the-air"
wiring, soldering items together suspended in air. For example, the
inverting input of a cmos opamp can be bent out from the rest, and
not put in a socket or soldered to the printed circuit board.
--
Thanks,
- Win
(email: use hill_at_rowland-dotties-org for now)
W
Winfield Hill
Guest
Achim Metzen wrote...
cmos opamp, e.g. something from NSC's LMC6001 family. They
say the LMC662 has an input current of only 2fA typical. You
should add additioanl static protection, which can consist of
a pair of back-to-back JFET gate-source diodes.
--
Thanks,
- Win
(email: use hill_at_rowland-dotties-org for now)
I think a good answer is to replace the tube amplifier with a
cmos opamp, e.g. something from NSC's LMC6001 family. They
say the LMC662 has an input current of only 2fA typical. You
should add additioanl static protection, which can consist of
a pair of back-to-back JFET gate-source diodes.
--
Thanks,
- Win
(email: use hill_at_rowland-dotties-org for now)
W
Winfield Hill
Guest
Winfield Hill wrote...
with 2fA typical bias, but it works at a lower power level using
55uA from a 3 to 16V source, better suited for battery power.
http://www.national.com/pf/LP/LPC661.html The production part is
the LPC661IM, which is in an 8-pin soic package. NSC offers free
samples, or they're in stock for $1.98 each at DigiKey.
--
Thanks,
- Win
(email: use hill_at_rowland-dotties-org for now)
The LPC661 may be a better choice. It's an NSC single cmos opamp
with 2fA typical bias, but it works at a lower power level using
55uA from a 3 to 16V source, better suited for battery power.
http://www.national.com/pf/LP/LPC661.html The production part is
the LPC661IM, which is in an 8-pin soic package. NSC offers free
samples, or they're in stock for $1.98 each at DigiKey.
--
Thanks,
- Win
(email: use hill_at_rowland-dotties-org for now)
C
Clint Sharp
Guest
In message <r35ok05pvt92b8kk8a5ok83nks9rrqnpl5@4ax.com>, Captain Rick
<ME@127.0.0.1> writes
Emulator isn't 3.3V compliant, it may also cause problems.
--
Clint Sharp
<ME@127.0.0.1> writes
machines are only 3.3v parallel ports.... if the interface on theI use a parallel port PIC programmer and had problems under XP with
the programming mode continually being reset (LED's flashing!). This
registry hack fixed it for me. It seems XP continually polls the
parallel port and this interferes with other uses.
[HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Parport\Parameters]
"DisableWarmPoll"=dword:00000001
Please let me know if it cures your problem - I will add it to my list
of "known cures"
Rick.
As an aside to this, are you aware that most Laptops and many desktop
Emulator isn't 3.3V compliant, it may also cause problems.
--
Clint Sharp
D
Dan Mills
Guest
Cedric wrote:
these guys do stupid big power using class E amplifiers at very high
efficency. Plenty of kits available.
Guessing at some sort of induction heating application?
Regards, Dan.
--
** The email address *IS* valid, do NOT remove the spamblock
And on the evening of the first day the lord said...........
..... LX 1, GO!; and there was light.
Look into the LF HAM stuff at IIRC 73Khz (also somewhere around 150K?),
these guys do stupid big power using class E amplifiers at very high
efficency. Plenty of kits available.
Guessing at some sort of induction heating application?
Regards, Dan.
--
** The email address *IS* valid, do NOT remove the spamblock
And on the evening of the first day the lord said...........
..... LX 1, GO!; and there was light.
R
Ron Reaugh
Guest
"nospam256K" <nospam256k@yahoo.com> wrote in message
news:24a23015.0409201837.1b40dbcd@posting.google.com...
news:24a23015.0409201837.1b40dbcd@posting.google.com...
Not dumb.
I always do it too.
J
John Popelish
Guest
nospam256K wrote:
and power supply at risk, if you happen to be near a ground
connection, your body is at some risk, also.
However, there is a simple precaution you can take that makes it much
safer to use your computer during a rain storm. Get a filtered, surge
suppressed power strip that has both receptacles and phone line
sockets. The surge suppressers help limit the voltage peaks between
any of the incoming power lines, which protects the supply, but also
limits the peak voltage between the phone lines and the power ground,
protecting both the modem and you from anything but a very close
strike. I still wouldn't use it in the bath tub, though.
Here is an example of one without a low pass filter (just surge
suppressers):
http://www.connectxpress.com/product.asp?cat%5Fid=4301&sku=29799
And a bigger unit that includes the RFI filter (that improves the
operation of the surge suppression a bit).
http://www.connectxpress.com/product.asp?cat%5Fid=4301&sku=29798
I am not endorsing these particular products, just using them as
examples of what I am talking about.
--
John Popelish
Your precautions are very sensible. Not only is the computer, modem
and power supply at risk, if you happen to be near a ground
connection, your body is at some risk, also.
However, there is a simple precaution you can take that makes it much
safer to use your computer during a rain storm. Get a filtered, surge
suppressed power strip that has both receptacles and phone line
sockets. The surge suppressers help limit the voltage peaks between
any of the incoming power lines, which protects the supply, but also
limits the peak voltage between the phone lines and the power ground,
protecting both the modem and you from anything but a very close
strike. I still wouldn't use it in the bath tub, though.
Here is an example of one without a low pass filter (just surge
suppressers):
http://www.connectxpress.com/product.asp?cat%5Fid=4301&sku=29799
And a bigger unit that includes the RFI filter (that improves the
operation of the surge suppression a bit).
http://www.connectxpress.com/product.asp?cat%5Fid=4301&sku=29798
I am not endorsing these particular products, just using them as
examples of what I am talking about.
--
John Popelish
O
Odd Bob
Guest
In article <24a23015.0409201837.1b40dbcd@posting.google.com>,
nospam256k@yahoo.com says...
lightning strike and I'm grateful that's all that was fried. These days
if I even think I hear thunder I pull all the plugs and go read a good
book. My suggestion, anyway...
-- Bob
nospam256k@yahoo.com says...
Very wise. A couple years back I had a modem fried by a nearby
lightning strike and I'm grateful that's all that was fried. These days
if I even think I hear thunder I pull all the plugs and go read a good
book. My suggestion, anyway...
-- Bob
S
Sporkman
Guest
The greatest danger is from your modem. Surges coming in through
telephone lines can do quite a bit of damage. In fact, I've had
desktops almost completely smoked via the modem. Fried the motherboard,
video, AND drives (both CD and HDD). Spared the RAM and the power
supply and not much else. And yes, it is absolutely certain that it was
through the telephone line, not through the power line. Surge
suppressors and uninterruptible power supplies MAY protect from
telephone line surges well enough, or they may not. After having a
computer smoked and having seen my neighbor's computer smoked in the
same way I stopped using internal modems altogether, but of course
external modems are seldom used with a laptop. Your computer power
supply will possibly protect your laptop well enough from power surges
with sacrificial diodes in the rectifier circuit, but it's a better bet
to unplug and run off the battery. I'm sure you don't want to even have
to buy a new AC supply for your laptop. Those can be expensive,
although Radio Shack carries AC supplies that MAY be enough for your
computer (mine actually requires more amperage than the RS model can
supply on startup, and if the battery is down the thing won't boot).
Mark 'Sporky' Stapleton
Watermark Design, LLC
www.h2omarkdesign.com
nospam256K wrote:
telephone lines can do quite a bit of damage. In fact, I've had
desktops almost completely smoked via the modem. Fried the motherboard,
video, AND drives (both CD and HDD). Spared the RAM and the power
supply and not much else. And yes, it is absolutely certain that it was
through the telephone line, not through the power line. Surge
suppressors and uninterruptible power supplies MAY protect from
telephone line surges well enough, or they may not. After having a
computer smoked and having seen my neighbor's computer smoked in the
same way I stopped using internal modems altogether, but of course
external modems are seldom used with a laptop. Your computer power
supply will possibly protect your laptop well enough from power surges
with sacrificial diodes in the rectifier circuit, but it's a better bet
to unplug and run off the battery. I'm sure you don't want to even have
to buy a new AC supply for your laptop. Those can be expensive,
although Radio Shack carries AC supplies that MAY be enough for your
computer (mine actually requires more amperage than the RS model can
supply on startup, and if the battery is down the thing won't boot).
Mark 'Sporky' Stapleton
Watermark Design, LLC
www.h2omarkdesign.com
nospam256K wrote:
W
Winfield Hill
Guest
Cedric wrote...
MOSFET H-bridge with phase-shift PWM.
--
Thanks,
- Win
(email: use hill_at_rowland-dotties-org for now)
I have made a 1kW 300kHz / 600kHz generator, using a
MOSFET H-bridge with phase-shift PWM.
--
Thanks,
- Win
(email: use hill_at_rowland-dotties-org for now)
B
Bigbazza
Guest
"Sporkman" <sporkedUNDERLINEagainMUNGE@bigfootDOT.com> wrote in message
news:414FA86C.E6EE30F@bigfootDOT.com...
used..But cable is !...So do I need to turn my Cable Modem off as well ..or
not..?..
Bigbazza
news:414FA86C.E6EE30F@bigfootDOT.com...
How about 'Cable Broadband ' delivery...Obviously a 'Telephone' is not
used..But cable is !...So do I need to turn my Cable Modem off as well ..or
not..?..
Bigbazza
T
Todd Copeland
Guest
"Bigbazza" <Bigbazza@nospam.com> wrote in message
news:2rae3qF17i62pU1@uni-berlin.de...
correct thing to do. I"ve had more analog modems fried by lightning (4) then
cable modems (2) but you can see, it happens. Personally I don't bother with
unplugging the cable modem as Brighthouse really does not have a problem
replaceing them with no charge.
news:2rae3qF17i62pU1@uni-berlin.de...
Turning it off would help. but _very_ little. Unplugging it would be the
correct thing to do. I"ve had more analog modems fried by lightning (4) then
cable modems (2) but you can see, it happens. Personally I don't bother with
unplugging the cable modem as Brighthouse really does not have a problem
replaceing them with no charge.
R
Roger Johansson
Guest
"Bigbazza" <Bigbazza@nospam.com> wrote:
underground cables there is very little risk for damage from lightning.
The high voltages from a lightning must then travel long distances
through underground cable systems, and the power is distributed among
thousands of end users connections.
There is probably also good protection systems in place to protect
against overvoltage conditions.
Earlier I lived in a small old house on top of a mountain, with
electricity and phone lines coming through the air, wires on poles.
Now that was a risky place to live at during lightning storms!
And there was often lightning hits even on clear days,
without any warning signals in the weather at all.
I have had my telephone practically explode a few feet from my head, and
I have had lots of equipment destroyed.
Mainly modems and tv sets but also other stuff.
Then I installed some protection components, spark gap devices, on both
the electricity and phone lines. Where the lines enter the house and
inside the house, close to the computer and tv set too. I also increased
the lightning protection for the house with lightning rods and lots of
wires in the ground around the house to absorb the power better.
That helped a lot, and I had no equipment destroyed for those 6 years
I lived there when I had the protection components installed.
Compared to my house on a mountain you are very well protected in a
densely populated city with underground cable systems for electricity,
phone lines, cable tv and cable internet.
A lot of people have a situation somewhere between these two extremes,
big city or mountain top, and may want to take necessary precautions.
The easiest way to add protection to vital equipment is to put all of it
on an extension cord with multiple outlets and add protection circuits to
that extension cord system. Make sure that both phone connection and
electricity connection are protected where they enter that extension cord
system.
--
Roger J.
If you live in a densely populated city and all these cables come through
underground cables there is very little risk for damage from lightning.
The high voltages from a lightning must then travel long distances
through underground cable systems, and the power is distributed among
thousands of end users connections.
There is probably also good protection systems in place to protect
against overvoltage conditions.
Earlier I lived in a small old house on top of a mountain, with
electricity and phone lines coming through the air, wires on poles.
Now that was a risky place to live at during lightning storms!
And there was often lightning hits even on clear days,
without any warning signals in the weather at all.
I have had my telephone practically explode a few feet from my head, and
I have had lots of equipment destroyed.
Mainly modems and tv sets but also other stuff.
Then I installed some protection components, spark gap devices, on both
the electricity and phone lines. Where the lines enter the house and
inside the house, close to the computer and tv set too. I also increased
the lightning protection for the house with lightning rods and lots of
wires in the ground around the house to absorb the power better.
That helped a lot, and I had no equipment destroyed for those 6 years
I lived there when I had the protection components installed.
Compared to my house on a mountain you are very well protected in a
densely populated city with underground cable systems for electricity,
phone lines, cable tv and cable internet.
A lot of people have a situation somewhere between these two extremes,
big city or mountain top, and may want to take necessary precautions.
The easiest way to add protection to vital equipment is to put all of it
on an extension cord with multiple outlets and add protection circuits to
that extension cord system. Make sure that both phone connection and
electricity connection are protected where they enter that extension cord
system.
--
Roger J.
C
Code Developer
Guest
"nospam256K" <nospam256k@yahoo.com> wrote in message
news:24a23015.0409201837.1b40dbcd@posting.google.com...
About a year ago, we had a thunder storm where a bolt of lightening actually
struck our back garden. The PC in the office was protected by a UPS /
filter, but the DSL connection through the phone line and the external
modem/router weren't protected. The lightening fried the modem and the
network card in the PC! Fortunately the rest of the PC was ok.
Now, the PC is protected by a UPS, and the modem/router's phone connection
is filtered through a surge protection device.
Regards,
Shaun.
news:24a23015.0409201837.1b40dbcd@posting.google.com...
No, very sensible!
About a year ago, we had a thunder storm where a bolt of lightening actually
struck our back garden. The PC in the office was protected by a UPS /
filter, but the DSL connection through the phone line and the external
modem/router weren't protected. The lightening fried the modem and the
network card in the PC! Fortunately the rest of the PC was ok.
Now, the PC is protected by a UPS, and the modem/router's phone connection
is filtered through a surge protection device.
Regards,
Shaun.
A
Alex Rodriguez
Guest
In article <24a23015.0409201837.1b40dbcd@posting.google.com>,
nospam256k@yahoo.com says...
Then you won't have to unplug everything. I would make sure that the phone
cable also runs through the surge protector or unplug it.
-----------------
Alex
nospam256k@yahoo.com says...
Sounds sensible to me. You could also try getting a good surge protector.
Then you won't have to unplug everything. I would make sure that the phone
cable also runs through the surge protector or unplug it.
-----------------
Alex
D
Dorothy Bradbury
Guest
There are 3 potential failures here:
o Data-corruption from power failure
---- for a laptop this risk is removed (usefully
o Modem is damaged thro telco system
---- not impossible even in NYC, not uncommon in rural or elsewhere
---- for an onboard modem you 1) lose your modem or 2) lose the laptop
---- both of which involve downtime & expense
o Computer is damaged through mains system
---- lightning will happily hit buildings, then run thro mains systems
It's not uncommon for lightning some distance away to cause line-drops,
as well as major power dips (brownouts/sags) and surges. Computer PSU
are switched-mode PSUs so tolerant of large variations in power, but that
is not a guarantee where lightning is concerned.
Telephone cables often run outside a building, along walls, which can be
interesting re picking up voltage from lightning or attraction.
When lightning appears to have gone, remember it can still strike some
distance from the originating storm - even in blue-sky. That is how most
people are struck by lightning, and potentially buildings, power poles etc.
If your power comes in thro a pole transformer, and same for telco, then
local lightning can pose a serious risk to both power & telephone services.
Colleague lost the corner of their tiny sub-let warehouse last year due to
a lightning strike - what wasn't burnt was electrically damaged.
So whilst it may seem old-fashiooned, it's not a bad idea.
Certainly unplugging the telco connection. In the UK the master telco socket
has a GDT, gas discharge tube, but if lightning is close they're a bit useless.
If something nearby is hit, the surge protectors can save a modem etc,
but a direct or very close strike will generally take out anything re energy.
--
Dorothy Bradbury
www.stores.ebay.co.uk/panaflofan for quiet Panaflo fans & other items
www.dorothybradbury.co.uk (free delivery)
o Data-corruption from power failure
---- for a laptop this risk is removed (usefully
o Modem is damaged thro telco system
---- not impossible even in NYC, not uncommon in rural or elsewhere
---- for an onboard modem you 1) lose your modem or 2) lose the laptop
---- both of which involve downtime & expense
o Computer is damaged through mains system
---- lightning will happily hit buildings, then run thro mains systems
It's not uncommon for lightning some distance away to cause line-drops,
as well as major power dips (brownouts/sags) and surges. Computer PSU
are switched-mode PSUs so tolerant of large variations in power, but that
is not a guarantee where lightning is concerned.
Telephone cables often run outside a building, along walls, which can be
interesting re picking up voltage from lightning or attraction.
When lightning appears to have gone, remember it can still strike some
distance from the originating storm - even in blue-sky. That is how most
people are struck by lightning, and potentially buildings, power poles etc.
If your power comes in thro a pole transformer, and same for telco, then
local lightning can pose a serious risk to both power & telephone services.
Colleague lost the corner of their tiny sub-let warehouse last year due to
a lightning strike - what wasn't burnt was electrically damaged.
So whilst it may seem old-fashiooned, it's not a bad idea.
Certainly unplugging the telco connection. In the UK the master telco socket
has a GDT, gas discharge tube, but if lightning is close they're a bit useless.
If something nearby is hit, the surge protectors can save a modem etc,
but a direct or very close strike will generally take out anything re energy.
--
Dorothy Bradbury
www.stores.ebay.co.uk/panaflofan for quiet Panaflo fans & other items
www.dorothybradbury.co.uk (free delivery)