Re: Schematic Symbols Book?
ARRL Ham radio handbook used to have a schematc section, but I have not look at recent one.
It aslo may be little too spendy just for schematic synbols.
(And since you have said you want a book I will not suggest
"google it" )
But you may try Eagle PCB software - it has an extensive component library you could retrieve symbols you want.
BTW I think there is no limit on schematic "size", you could use ti to build your schematic only.
Vaclav
PS I hope references to PCB software are legal here, if not I'll delete this if necessary and reply privately. I posted it to the group because I feel the group may benefit.
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Plugging holes in bakelite.
For the new generations of electronics hobbyists here - there was a time when radio "boxes" were made from one of the first plastics invented - bakelite. So this is related to electrons in some strage way.
I have a box made in early fifties - that is 1950's.
It has some unwanted holes I would like to fill.
The challenge is - bakelite is temperature unfriendly, so I cannot use any thermosetting goop.
Of course it also needs to be polished and colored to match.
Any experienced old time radio restorer lurks here ?
Vaclav
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Re: LCD monitor power supply
An excelllent source for a variety of power supplies is Marlin P. Jones
Associates, Inc., located in
Lake Park, Florida (www. mpja.com). Prices are very reasonable, and a
wide variety of linear and
switch-mode power supplies are available. MPJ is always my first choice
when I need a power
supply.
Another thought: "Wall Warts" are not (generally) NOT regulated. A
"nominal" voltage is usually
specified on the unit, but since they are not regulated, the actual
voltage delivered to the device
being powered can vary a great deal, proportionate to the V/I demand of
the device being powered.
Switch-mode power supplies are almost always regulated, and these are
they types of supplies
that are used with computer monitors, etc.
IMHO, using an unregulated "wall wart" to powrer some devices can lead
to drastic disaster
at worst, and poor and erratic operation at best.
MPJ usually has in stock, a variety of switch-mode, regulated "bricks"
that are reasonably priced.
I never attempt to repair a failed switch-mode brick..............it
just not economically worth the
effort........that is.........if you can ever actually repair the
blasted thing and get back to spec.
For example: MPJ shows several 12VDC bricks with 1 Amp, up to 4 Amp
capability at prices
around 10 to 15 bucks.
Can't beat MJP's prices, variety, and fast shipment.
Spend your time designing something that's fun and useful.
Roland F. Harriston, P.D.
****
Roland F. Harriston
Andrew Villeneuve wrote:
toggle quoted message
Show quoted text
I've actually had this exact same problem ( 19" LCD with a 12V/4A power
brick that burnt out ), and since I had a pair of 12V/2A wall-warts laying
around, I ganged them together in parallel. Seems to work great.
Barring that, my standard approach to these problems would just be to hook
up a spare ATX power supply - you can usually find them for free in
old PCs
that people throw away because they're underpowered they don't know how to
clean up their virus collection.
-Andrew
On Wed, Jan 19, 2011 at 11:27 AM, Reese <reeza@...
<mailto:reeza%40reeza.com>> wrote:
I have a bad news story. The 100-240 v input, 12v 4A output power brick
that sends power to my 19" LCD monitor apparently took a dump overnight.
An LED on the brick does not light up properly, I can't measure anything
on the output side. I've already looked in my spare parts piles, I do
not have any power bricks or wallwarts that come close enough.
I'm in the process of opening the plastic case, to see if anything is
obviously wrong and can easily be fixed. It's glued (no screws) so it
is slow going with a hobbyist slitting saw:
<
On the chance that the brick is properly toasted and cannot be fixed,
what are some other options for 12vdc @ 4a to power the monitor?
Yes, I can Google for something, but I thought I'd ask here first. If
something quick and easy makes for a good project build, why not do
that instead of rushing of to purchase a turnkey item?
Reese
|
Re: LCD monitor power supply
My 12v LCD is still working fine with a 19v supply.? Am I slowly burning it up?? Do DC appliances have built-in voltage regulators to protect them from lazy cheapskates like me?? Couldn't I change out a couple of components in the supply to change it to 12V?? Maybe I am lucky but I've never had trouble cheating this way.
Mark
toggle quoted message
Show quoted text
--- On Sun, 1/23/11, Andrew Villeneuve <andrewmv@...> wrote: From: Andrew Villeneuve <andrewmv@...> Subject: Re: [Electronics_101] LCD monitor power supply To: Electronics_101@... Date: Sunday, January 23, 2011, 10:48 PM ? I've actually had this exact same problem ( 19" LCD with a 12V/4A power brick that burnt out ), and since I had a pair of 12V/2A wall-warts laying around, I ganged them together in parallel. Seems to work great. Barring that, my standard approach to these problems would just be to hook up a spare ATX power supply - you can usually find them for free in old PCs that people throw away because they're underpowered they don't know how to clean up their virus collection. -Andrew On Wed, Jan 19, 2011 at 11:27 AM, Reese <reeza@...> wrote: I have a bad news story. The 100-240 v input, 12v 4A output power brick that sends power to my 19" LCD monitor apparently took a dump overnight. An LED on the brick does not light up properly, I can't measure anything on the output side. I've already looked in my spare parts piles, I do not have any power bricks or wallwarts that come close enough. I'm in the process of opening the plastic case, to see if anything is obviously wrong and can easily be fixed. It's glued (no screws) so it is slow going with a hobbyist slitting saw: <
On the chance that the brick is properly toasted and cannot be fixed, what are some other options for 12vdc @ 4a to power the monitor? Yes, I can Google for something, but I thought I'd ask here first. If something quick and easy makes for a good project build, why not do that instead of rushing of to purchase a turnkey item? Reese [Non-text portions of this message have been removed]
|
Re: LCD monitor power supply
I've said this many times - discussions of general PC software help are off-topic here.
Add to that, you are hijacking a thread.
Steve Greenfield AE7HD
Your grumpy neighborhood moderator
toggle quoted message
Show quoted text
--- In Electronics_101@..., John Eh <jwoolsey@...> wrote:
How do you clean up the virus collection on aging PCs. I get asked that
by home users all the time. Some of them have virus protection. Is there
something Open Source that is any good? I don't want to touch their
machines due to "you broke it syndrome".
thanks
John
On 1/23/2011 10:48 PM, Andrew Villeneuve wrote:
I've actually had this exact same problem ( 19" LCD with a 12V/4A power
brick that burnt out ), and since I had a pair of 12V/2A wall-warts laying
around, I ganged them together in parallel. Seems to work great.
Barring that, my standard approach to these problems would just be to hook
up a spare ATX power supply - you can usually find them for free in old PCs
that people throw away because they're underpowered they don't know how to
clean up their virus collection.
-Andrew
On Wed, Jan 19, 2011 at 11:27 AM, Reese<reeza@...> wrote:
I have a bad news story. The 100-240 v input, 12v 4A output power brick
that sends power to my 19" LCD monitor apparently took a dump overnight.
An LED on the brick does not light up properly, I can't measure anything
on the output side. I've already looked in my spare parts piles, I do
not have any power bricks or wallwarts that come close enough.
I'm in the process of opening the plastic case, to see if anything is
obviously wrong and can easily be fixed. It's glued (no screws) so it
is slow going with a hobbyist slitting saw:
<
On the chance that the brick is properly toasted and cannot be fixed,
what are some other options for 12vdc @ 4a to power the monitor?
Yes, I can Google for something, but I thought I'd ask here first. If
something quick and easy makes for a good project build, why not do
that instead of rushing of to purchase a turnkey item?
Reese
|
Re: Accelerometer to measure velocity
I think any kind of electronic system is worthless in this case.
What you need is a kind of elevator safety break.
It will work no matter what, even if it looks like this:
<>
ST
|
Re: Accelerometer to measure velocity
In article <ihjaa8+r7de@...>, Michael <mmk_tsm@...> wrote: Activate the brake. That is the whole point of the exercise Which will stop the winch and the rope which is still attached but not the bit, with the load, that has broken away and is already in freefall! -- Stuart Winsor Midland RISC OS show - Sat July 9th 2011
|
Re: Accelerometer to measure velocity
Activate the brake. That is the whole point of the exercise.
toggle quoted message
Show quoted text
--- In Electronics_101@..., lists <Stuartlists@...> wrote:
In article <519a5a2284Stuartlists@...>,
lists <Stuartlists@...> wrote:
In article <ihifep+tl6g@...>,
Michael <mmk_tsm@...> wrote:
Stuart,
what if the lift rope breaks???? If you're using the winch within it's designed limits and you regularly
inspect and maintain all your lifting gear as you should, it shouldn't
happen. P.S. If the rope breaks there's bugger all you can do about it anyway.
--
Stuart Winsor
Midland RISC OS show - Sat July 9th 2011
|
Source for 5KV ac supply?
Googling gets many hits for dell, sony, and other power supply replacements (5000 being a model number or part number, not an output voltge...)
Anyone know of a surplus or other cheapie source? Or plans?
Extra points for variable...
Thanks,
Dave
|
Re: Strange issue with LED Bulb
You are welcome :) ________________________________ From: Donald H Locker <dhlocker@...> To: Electronics 101 <Electronics_101@...> Sent: Sun, January 23, 2011 9:09:12 AM Subject: Re: [Electronics_101] Re: Strange issue with LED Bulb A good lesson here is that a reference schematic is not the same as a reference board layout. In many cases, part placement is as important as part value. Thanks for the report on the solution, Sanmeet. Donald. -- *Plain Text* email -- it's an accessibility issue () no proprietary attachments; no html mail /\ ascii ribbon campaign - <www.asciiribbon.org> ----- Original Message ----- From: "Sanmeet H" <sanmeeth@...>
To: "E_101 Group" <Electronics_101@...>
Sent: Tuesday, January 18, 2011 11:10:16 PM
Subject: [Electronics_101] Re: Strange issue with LED Bulb
I got the cause of the bug. The SMPS IC Vcc cap is located around 20cm
from the VCC pin. The Inductor and FET are closer to the SMPS IC and are
probably causing noise. Shifting the (ceramic)cap nearer (5mm) to the Vcc pin
lessened the problem. Increasing the Vcc ceramic and 'lytic cap took care of
the
problem fully in all the power supplies.
Sanmeet
________________________________
From: Sanmeet H <sanmeeth@...>
To: E_101 Group <Electronics_101@...>
Sent: Mon, January 17, 2011 12:32:11 PM
Subject: Strange issue with LED Bulb
Hi,
I have made a 3 to 6 LED bulb driver using TI PFC controlller SMPS IC -
UCC28600. My schematic is exactly same as TI's reference schematic. I have
uploaded the schematic in files section---> LED BULB.pdf.
Everything is working fine but I have a strange problem. If I switch OFF a
working bulb and switch ON again within say 1 second, the LED start ON /OFF
cycling. ON for approx 0.5 sec and OFF for around 1 sec.
If the Power is switched OFF for more than 1 second and restored, the LED's
work just fine. I have made around 10 bulbs. All have the exact same issue.
Does anyone have a clue as to what is the reason... Any advice would be
appreciated.
Sanmeet H
|
Re: LCD monitor power supply
I've actually had this exact same problem ( 19" LCD with a 12V/4A power
brick that burnt out ), and since I had a pair of 12V/2A wall-warts laying
around, I ganged them together in parallel. Seems to work great.
Barring that, my standard approach to these problems would just be to hook
up a spare ATX power supply - you can usually find them for free in old PCs
that people throw away because they're underpowered they don't know how to
clean up their virus collection.
-Andrew
toggle quoted message
Show quoted text
On Wed, Jan 19, 2011 at 11:27 AM, Reese <reeza@...> wrote:
I have a bad news story. The 100-240 v input, 12v 4A output power brick
that sends power to my 19" LCD monitor apparently took a dump overnight.
An LED on the brick does not light up properly, I can't measure anything
on the output side. I've already looked in my spare parts piles, I do
not have any power bricks or wallwarts that come close enough.
I'm in the process of opening the plastic case, to see if anything is
obviously wrong and can easily be fixed. It's glued (no screws) so it
is slow going with a hobbyist slitting saw:
<
On the chance that the brick is properly toasted and cannot be fixed,
what are some other options for 12vdc @ 4a to power the monitor?
Yes, I can Google for something, but I thought I'd ask here first. If
something quick and easy makes for a good project build, why not do
that instead of rushing of to purchase a turnkey item?
Reese
|
Re: Accelerometer to measure velocity
Me, my wife, Jane, and son, Boy, are supporting the whole thing via a
vine, a non-cannibis vine, in this theoretical exam
toggle quoted message
Show quoted text
On 1/23/2011 7:00 PM, Michael wrote:
Stuart,
what if the lift rope breaks????
--- In Electronics_101@...
<mailto:Electronics_101%40yahoogroups.com>, lists <Stuartlists@...> wrote:
In article <ihh7i8+7as8@...>,
Michael <mmk_tsm@...> wrote:
Thanks Derek, but as I wrote, it is unlikely the object would
reach full
freefall. It might run away, but there would be some friction, so
it would never reach a full free fall situation. Do you think I
could detect for example travel at twice expected speed? You mentioned "winch" so the easiest way is to measure rpm and set an
alarm or whatever on that
--
Stuart Winsor
Midland RISC OS show - Sat July 9th 2011
------------------------------------------------------------------------
No virus found in this message.
Checked by AVG - www.avg.com <>
Version: 10.0.1191 / Virus Database: 1435/3398 - Release Date: 01/23/11
|
Re: Accelerometer to measure velocity
In article <519a5a2284Stuartlists@...>, lists <Stuartlists@...> wrote: In article <ihifep+tl6g@...>,
Michael <mmk_tsm@...> wrote:
Stuart,
what if the lift rope breaks???? If you're using the winch within it's designed limits and you regularly
inspect and maintain all your lifting gear as you should, it shouldn't
happen. P.S. If the rope breaks there's bugger all you can do about it anyway. -- Stuart Winsor Midland RISC OS show - Sat July 9th 2011
|
Re: Accelerometer to measure velocity
In article <ihifep+tl6g@...>, Michael <mmk_tsm@...> wrote: Stuart,
what if the lift rope breaks???? If you're using the winch within it's designed limits and you regularly inspect and maintain all your lifting gear as you should, it shouldn't happen. -- Stuart Winsor Midland RISC OS show - Sat July 9th 2011
|
Re: Accelerometer to measure velocity
If speed measurement is critical, then using an accelerometer may not be the best method since you need to know acceleration history and there is always some errors. Best is to measure velocity direct. If you have a winch, put a roller on the cable and measure velocity that way. Adds little friction to the system, just measure rotation velocity and perform simple math calculation.
Derek Koonce
DDK Interactive Consulting Services
toggle quoted message
Show quoted text
On 1/23/2011 4:39 AM, Michael wrote:
Thanks Derek,
but as I wrote, it is unlikely the object would reach full freefall. It might run away, but there would be some friction, so it would never reach a full free fall situation.
Do you think I could detect for example travel at twice expected speed?
--- In Electronics_101@... <mailto:Electronics_101%40yahoogroups.com>, Derek Koonce <derek@...> wrote:
To know when an object is in free fall, the acceleration is 0. Thus it
is easy to measure, so long as you know what is up. I have used a
3-axis
accelerometer without any issues. Quite easy. Look at Kionix products. I
have this in a project right now.
Derek Koonce
DDK Interactive Consulting Services
On 1/22/2011 1:24 PM, Michael wrote:
Hello All,
I have been doing some reading, re using an accelerometer to measure
velocity. I want to detect when an object is travelling too fast. It
is an up/down or vertical movement, and maximum travel is only about
2m. Essentially I want to detect when object is falling, but it might
not be in total freefall. The winch might fail, but there would still
be some slowing friction.
Has anyone used an acceleromter for this type of application, can it
work, what accuracies are needed, etc, etc?
Any advice would be much appreciated,
Mike.
|
Re: Accelerometer to measure velocity
Stuart,
what if the lift rope breaks????
toggle quoted message
Show quoted text
--- In Electronics_101@..., lists <Stuartlists@...> wrote:
In article <ihh7i8+7as8@...>,
Michael <mmk_tsm@...> wrote:
Thanks Derek, but as I wrote, it is unlikely the object would reach full
freefall. It might run away, but there would be some friction, so
it would never reach a full free fall situation. Do you think I
could detect for example travel at twice expected speed? You mentioned "winch" so the easiest way is to measure rpm and set an
alarm or whatever on that
--
Stuart Winsor
Midland RISC OS show - Sat July 9th 2011
|
Re: Accelerometer to measure velocity
In article <ihh7i8+7as8@...>, Michael <mmk_tsm@...> wrote: Thanks Derek, but as I wrote, it is unlikely the object would reach full
freefall. It might run away, but there would be some friction, so
it would never reach a full free fall situation. Do you think I
could detect for example travel at twice expected speed? You mentioned "winch" so the easiest way is to measure rpm and set an alarm or whatever on that -- Stuart Winsor Midland RISC OS show - Sat July 9th 2011
|
Electronic devices Floyd 8th edition
I am in my first year of BMET classes and was wondering if anybody had any study guides or old quizes from the electronics devices 8th edition by Floyd.
Thanks
Eric
|
Hi,
I have a door intercom with built in camera. The audio and door opening part of the intercom is working fine. But, the camera doesn't work. Hence, I can not see any video on it. I don't think there camera is faulty.
I have got a Commax DPV 4HP intercom. I was wondering that do you know what would be the best way to debug it and get it to work? The manual don't have a circuit or PCB diagram either.
Thank you for your conisderations.
|
Re: Accelerometer to measure velocity
Thanks Derek,
but as I wrote, it is unlikely the object would reach full freefall. It might run away, but there would be some friction, so it would never reach a full free fall situation.
Do you think I could detect for example travel at twice expected speed?
toggle quoted message
Show quoted text
--- In Electronics_101@..., Derek Koonce <derek@...> wrote:
To know when an object is in free fall, the acceleration is 0. Thus it
is easy to measure, so long as you know what is up. I have used a 3-axis
accelerometer without any issues. Quite easy. Look at Kionix products. I
have this in a project right now.
Derek Koonce
DDK Interactive Consulting Services
On 1/22/2011 1:24 PM, Michael wrote:
Hello All,
I have been doing some reading, re using an accelerometer to measure
velocity. I want to detect when an object is travelling too fast. It
is an up/down or vertical movement, and maximum travel is only about
2m. Essentially I want to detect when object is falling, but it might
not be in total freefall. The winch might fail, but there would still
be some slowing friction.
Has anyone used an acceleromter for this type of application, can it
work, what accuracies are needed, etc, etc?
Any advice would be much appreciated,
Mike.
|
Steven AE7HD
Derek Koonce