Marriage is under fire!!

[legg]

On Thu, 2 Sep 2004 21:25:33 -0600, "Travis Hayes"
<tmh-SPAMISSPICEDHAM@nerdshack.com> wrote:

Here is my question: He's come to me, asking how he can hold the start
voltage to 4kV, while not impacting the voltage during normal operation. My
experience is all in the sub-1kV range, so I'm not quite sure what to
suggest. My personal opinion is that this is one of those penny-wise,
pound-foolish ideas, but I'm looking for suggestions, none the less.

The cold-starting voltage and operating current of the lamp will
depend on the combination of the lamp and ballast characteristics. The
ballast has been designed for the lamp intended. It would have to be
modified for another lamp with different characteristics and
requirements, or a suitable ballast used.

Failure of these lamps can be explosive, so you shouldn't mess around
without adequate eye protection.

What are the two lamp type numbers?

RL

 

[Michael A. Covington]

Everybody is less expensive than Radio Shack

For wide selection:
www.digikey.com
www.mouser.com

For low prices and surplus:
All Electronics Corp.
Halted Specialties
And numerous others that advertise in the magazine Nuts & Volts.

 

[Michael A. Covington]

Please let me know if there is a better way to set this up...as I'm a
novice, any feedback would be appreciated!

Put the lamps in the collector lead rather than the emitter lead of the
transistors.

As it is, you are using the outputs as emitter follower voltage regulators.
The lamps do not get full voltage. They get 0.6V less than the output
voltage of the PIC.

 

[Travis Hayes]

Thanks to all for your good input.
I agree that the best way to go would be to either spend the money for
the proper bulbs, or to replace the projector with one which uses less
expensive bulbs.
I thought of MOVs at first, but my experience with them is that they are
designed to dissipate a large amount of power for a very short amount of
time, and would likely not survive long with a 1 second surge. That, and
they tend to deteriorate over time and eventually fail as an open.
The concensus seems to be that it is _not_ the starting voltage that
would be causing the bulbs to fail, but rather an overvoltage during normal
running.
Unfortunately, I have not actually seen either of the bulbs in question;
so far all of my information has been gleaned on the phone with him; I don't
know any specifications of the bulb that he is trying to replace.
Thanks again for your help.

 

[onestone]

Why not ask in aus.electronics, and give a little more information,
incluidng a few basic details, and how much you'd expect to pay.

Al

Craig Curtin wrote:

Guys,

I know a little about electronics (enough to be dangerous) but not
enough to undertake a project that i need created.

Is this the right place to ask ??

I am happy to pay for the work and all parts required.

I am in Sydney and would ideally like a Sydney based enthusiast to
take on the work.

Email me at craig.curtin@gmail.com if you are interested.

Craig

 

[legg]

On Fri, 3 Sep 2004 19:00:39 -0600, "Travis Hayes"
<tmh-SPAMISSPICEDHAM@nerdshack.com> wrote:

The concensus seems to be that it is _not_ the starting voltage that
would be causing the bulbs to fail, but rather an overvoltage during normal
running.
Unfortunately, I have not actually seen either of the bulbs in question;
so far all of my information has been gleaned on the phone with him; I don't
know any specifications of the bulb that he is trying to replace.

Is your associate actually measuring terminal voltages, or just
reading the manual?

The igniter can generally produce double the nominal breakover
voltage, if a lamp is not present to clamp it (due to internal
break-over).

Continuous operation with a damaged or removed lamp can overstress the
igniter through overheating - it is normally disabled by the reduced
voltage present when the lamp starts to discharge.

RL

 

[john doe]

JR North <jasonrnorth@bigfoot.com> wrote

I hope I can finish this before my system stalls.....
I have a thermal failure in my motherboard, which is causing
the system to stall as it warms up. It's a 1 gig Athalon
Socket A which uses SDRAM. All the current boards say DDR
sockets. Will a DDR memory motherboard accept the 1.5 GB
SDRAM I have on my board, or do I have to pony up for DDR
memory too when I replace it?

You could salvage two of the cips if you need to.

http://www.zipzoomfly.com/jsp/ProductDetail.jsp?ProductCode=241051

MSI KM2M Combo-L

Later you could pony up for DDR memory and later still you could upgrade
to a better mainboard, give the Combo-L to your little brother (or
sister), and take the two DDRs with you. Pay as you go.

But better IMO to do it all at once if possible.

Good luck.





--
I realize this reply might be too late for the individual, but it might
be a common question.

 

[Rich Grise]

Dummy wrote:

Finally, the root cause of the distortion had been found.
There were four screws on the radios. The screws serves the purpose of
holding radio PCB and chassis together. When one of the screws was
removed, somehow, no distortion was seen at DTMF tone! That screw
(contacted to ground) resided very near to 7.5V supply line in third
layer of PCB layout. But I was still a bit bewildered on what happened
actually. Could you please shed some lights?

The four mounting posts aren't coplanar, so when you tighten the fourth
screw, it warps the board.

Cheers!
Rich

 

[Rich Grise]

Wrong - never mind.

Rich Grise wrote:

John Fields wrote:

On 3 Sep 2004 10:41:33 -0700, alex1138@charter.net (Alex Bryant)
wrote:

I have posted a schematic of this setup at:

https://home.comcast.net/~alex1138/

Please let me know if there is a better way to set this up...as I'm a
novice, any feedback would be appreciated!

---
1. Make sure the transistors can take 300mA of collector current
without coming out of saturation.

2. Connect one side of each the lamps to +6V.

3. Connect the other side of each lamp to the COLLECTOR of its
transistor.

4. Connect all of the transistor EMITTERS to -6V.

5. Replace the 10K resistors with 330 ohm resistors.

And invert the logic of your outputs.

That should do it

Cheers!
Rich

 

[KevinR]

On 3 Sep 2004 21:02:23 -0700, craig.curtin@gmail.com (Craig Curtin)
wrote:

Hi guys,

We are doing some renovations at home (Sydney Australia) and as part
of this we are going to implement a Hydronically heated floor.
(basically pump hot water through a slab)
This will be in and running for next winter.

What i need built is essentially a fancy differential temperature
controller - as i can not find anything even remotely similar on the
market that will do everything that i want.

I will have a storage tank of hot water which i will need to monitor
the temperature of - during the day this will be heated by a solar
setup on the roof so i will need to be able to have a settable
temeprature difference between the two that would control a 24v relay.
e.g. Lets say i set that i want the tank to be at a maximum of 40
degreee C. (Set point 1) So this would need one temperature probe that
could be positiioned in/on the tank

I also want to set that if the roof is 5 degrees (or more) warmer than
the tank (and the tank is not at 40 degrees) then turn on the relay
(which will activate a small circulating pump). In the event that the
differential temperature becomes less than 5 degrees turn off the pump

The system would then need to have a 2nd Set point for monitoring the
room temperature (lets say i set that to 22 degrees) ( I would
actually like a couple of these inputs (say 3) for 3 seperate
thermostats) which the system could monitor and have seperate outputs
(relay) for each one. (So i could have 3 different areas that were
being monitored and potentially running at different temperatures)

Each of these outputs would be tied into a "master" so if any were
active the master was also active - this would drive a relay which
would drive a circulating pump and finally the outputs of each of the
3 zones would then drive a solenoid for each zone that would be on or
off

Lastly a time controller that could contol the different temperatures
for potentially differnet times of the day - so for instance the Home
theatre would run at 18 degress during the day but at 5PM would raise
the temperature to 22, whereas the laundry and bathroom area would run
at 22 degrees during the day and then go down to 15 degress overnight
??

All of this would have some form of LCD interface to enable the
monitoring and setting of each of the elements

Any ideas how i would go about this - i am not up on Electronics but
do COmputer systems for a living.

Craig

As you are already familiar with computer systems, how about a PC
based solution using something like National Instruments
multi-function card

http://sine.ni.com/apps/we/nioc.vp?cid=14117&lang=US

They also do some software called Labview. which is a visual
programming thingy where you just use drag and drop and a minimum of
coding.

National Instruments aren't the cheapest for this sort of stuf, there
are other manufacturers.

Another option is a PLC, but by the time you have added an LCD
display, it becomes more expensinve than a PC based version.

Kevin R

 

[Si Ballenger]

On Fri, 3 Sep 2004 20:17:05 -0400, "Michael A. Covington"
<look@ai.uga.edu.for.address> wrote:

Everybody is less expensive than Radio Shack

For wide selection:
www.digikey.com
www.mouser.com

For low prices and surplus:
All Electronics Corp.
Halted Specialties
And numerous others that advertise in the magazine Nuts & Volts.

I get pretty good service from bgmicro below:

http://www.bgmicro.com/catalog.asp

 

[Joerg]

Hi,

I don't think that's the problem. When washer or insulator was mounted
on the screw ground pad, no DTMF distortion was seen after the fourth
screw been tightened.


That sounds like either the screw may be touching some traces down in

the PCB or, more likely, you have a serious case of a ground loop. Do
both boards have a full ground plane?

Regards, Joerg

http://www.analogconsultants.com

 

[Joe]

"Robert C Monsen" <rcsurname@comcast.net> wrote in message
news:yN4_c.121481$mD.11768@attbi_s02...

"John Fields" <jfields@austininstruments.com> wrote in message
news:98jgj0l52jma204nu2vbkj1pbdqi1f5mc6@4ax.com...
On Fri, 03 Sep 2004 00:34:17 GMT, "Joe"
nuisancewildlife@nospamearthlink.net> wrote:



Thank you John,

As I said previously, I have a lot of difficulty with ascii
schematics. I
copied the complete post and will have to go thru it slowly to try
and
understand it. Is there a site I can visit for a tutorial on ascii
schematics? I am seeing more and more of them lately. I just don't
understand what some of the symbols mean and how they are connected.

---
It's fairly easy, but different folks use slightly different
conventions sometimes, so it gets confusing. Basically, here's what
I
do:

|
|
Vertical wire: |
|
|


Horizontal wire: ---------------

| |
| |
Wires crossing but not connected: ---|--- or -------
| |
| |
|
|
Wires connected: ---+-+---
|
|


2-leaded components:

Basically, describe what it is with an alpha designation in
brackets,
put some wires on it, and connect it to something.

Horizontal R1
Resistor --[100K]-- or --[100K]-- or --[R1]-- or --[R]--


Vertical R1| | | |
Resistor [100K] or [100K] or [R1] or [R]
| | | |


Horizontal C1
Capacitor --[100ľF]-- or --[100ľF]-- or --[C1]-- or --[C]--


Show polarity where needed, like for electrolytic capacitors:

C1 + |+
--[100ľF]-- or [100ľF]
|

and diodes:

A = Anode
K = Cathode =
K |A
--[1N4000>]-- OR --[1N4000]-- OR [1N4000]
|



For transistors and FETs, label the terminals and put in aything
else
you need to :

| |
Q1 C D
---B NPN ---G
2N4401 E 2N7000 S
| |


For opamps and comparators:


---|+\
| >--
---|-/


For larger blocks, identify the part, label the connections and
enclose them in a box. I like to use +'s for the corners, other
folks
use dots or single quotes or commas. Add pin numbers if you like,
or
whatever will make your meaning clear


+---------+
----|TR- |
----|TH OUT|----
----|D |
+---------+
555


For switches:

____
---O O--- or ---> |
|
O



Then just hook it all up:



+12 +12 +12
| | |
[10K] [10K] 555 [1M]
| | +---------+ |
| <--+-[0.1ľF]-+----|TR- OUT|---|---->OUT
| | | |
O | DIS|---+
| | | |
GND | TH|---+
+---------+ |+
[1ľF]
|
GND

That's a 555 timer which puts out a pulse about 1 second long each
time you press the switch.


Also, there's a free ASCII schematic drawing program out there which
a
lot of people use to post stuff to the non-binary newsgroups. I
forget what its name is (Andy's something-or-other, I think) and the
link to it, but I'm sure somebody will post that info if you ask for
it or if they read this.


Andy´s ASCII-Circuit v1.25.250804 www.tech-chat.de

--
John Fields

Thanks Robert,

I will download it. I visited the site, but did not go to the download
section, I hope I don't have to speak German to understand it.

Joe

 

[Gordon Youd]

Heated floor in Australia???, come on, I thought your country was Phooo!
hot!!

How can you get rid of the latent heat in the floor during the day?

Kind regards, Gordon.

----------------------------------------------------------------------------
---------------
"Craig Curtin" <craig.curtin@gmail.com> wrote in message
news:266c18c8.0409032002.5a77f2e5@posting.google.com...

Hi guys,

We are doing some renovations at home (Sydney Australia) and as part
of this we are going to implement a Hydronically heated floor.
(basically pump hot water through a slab)
This will be in and running for next winter.

What i need built is essentially a fancy differential temperature
controller - as i can not find anything even remotely similar on the
market that will do everything that i want.

I will have a storage tank of hot water which i will need to monitor
the temperature of - during the day this will be heated by a solar
setup on the roof so i will need to be able to have a settable
temeprature difference between the two that would control a 24v relay.
e.g. Lets say i set that i want the tank to be at a maximum of 40
degreee C. (Set point 1) So this would need one temperature probe that
could be positiioned in/on the tank

I also want to set that if the roof is 5 degrees (or more) warmer than
the tank (and the tank is not at 40 degrees) then turn on the relay
(which will activate a small circulating pump). In the event that the
differential temperature becomes less than 5 degrees turn off the pump

The system would then need to have a 2nd Set point for monitoring the
room temperature (lets say i set that to 22 degrees) ( I would
actually like a couple of these inputs (say 3) for 3 seperate
thermostats) which the system could monitor and have seperate outputs
(relay) for each one. (So i could have 3 different areas that were
being monitored and potentially running at different temperatures)

Each of these outputs would be tied into a "master" so if any were
active the master was also active - this would drive a relay which
would drive a circulating pump and finally the outputs of each of the
3 zones would then drive a solenoid for each zone that would be on or
off

Lastly a time controller that could contol the different temperatures
for potentially differnet times of the day - so for instance the Home
theatre would run at 18 degress during the day but at 5PM would raise
the temperature to 22, whereas the laundry and bathroom area would run
at 22 degrees during the day and then go down to 15 degress overnight
??

All of this would have some form of LCD interface to enable the
monitoring and setting of each of the elements

Any ideas how i would go about this - i am not up on Electronics but
do COmputer systems for a living.

Craig

 

[John Popelish]

mask wrote:

Thanks, I appreciate your responses on everything. I picked up 'The
Art of Electronics' and the student guide to go with it.. Within
reading just the first few pages things have already become much
clearer.

Excellent! If you have other questions, don't hesitate to ask.
There are many who lurk and learn from the questions others pose.
And they go into the archive for people to search through, later.

--
John Popelish

 

[Tim Auton]

"Rodney Kelp" <Rodneykelp605@hotmail.com> wrote:

Maybe this is off topic but does anybody know how you convert the gps
position coordinace to distance? For instance If I am currently at
44 degrees 18 minutes 35.3 seconds lattitude and 69 46 52.4 longtitude and
I move to 44 18 35.3 by 69 46 54.0 how many feet have I moved easterly? I
can't seem to find any conversion tables that convert degrees, minutes,
seconds to feet. Am I expecting too much?

Yes. If you imagine the lines on a globe you'll note the lines of
longitude get closer together as you apprach the poles - in other
words one degree of longitude is not a constant distance along the
ground. Latitude is easier: one minute is one nautical mile
(approximately).

My GPS receiver will give me coordinance and speed in miles per hour and
direction but not the distance traveled. What's up with that?

You need a more expensive GPS

Or you could use this handy page:

http://jan.ucc.nau.edu/~cvm/latlongdist.html

Once you know how far a degree/minute/second is for your location it
should be a good enough approximation for the local area.


Tim
--
Guns Don’t Kill People, Rappers Do.

 

[Rich Webb]

On Sun, 5 Sep 2004 16:12:27 -0400, "Rodney Kelp"
<Rodneykelp605@hotmail.com> wrote:

Maybe this is off topic but does anybody know how you convert the gps
position coordinace to distance? For instance If I am currently at
44 degrees 18 minutes 35.3 seconds lattitude and 69 46 52.4 longtitude and
I move to 44 18 35.3 by 69 46 54.0 how many feet have I moved easterly? I
can't seem to find any conversion tables that convert degrees, minutes,
seconds to feet. Am I expecting too much?

For a local approximation, consider 1 minute of latitude to be exactly
1852 meters, which is 1 nautical mile or about 6076 feet. Then 1 minute
of longitude is 1852 meters times the cosine of your latitude. Neither
is strictly true (we live on a lumpy planet) but close enough.

So, you moved 1.6 seconds of arc (0.027 minutes) to the east (assuming
your positions above are N and W) or about 116 feet.

A "flat earth" approximation like this fine as long as you stay in
about the same general area. In the example above, if the starting
points had been 1 nm (1 minute) further north then the change in
distance traveled to the east would be less than an inch.

If you can, record the GPS positions at your boundary spots for some
period of time and pick the center of the spread. This estimate will
probably be your largest error source. Use WAAS or differential if your
equipment supports it.

For larger areas (or more exacting work) you'd need to work in spherical
trig and great circle distances, or go beyond that and work with the
shape of the WGS-84 ellipsoid and the local geoid. But as long as the
"flat earth" approximation errors are less than a tenth or so of your
position estimate errors, you should be just fine in going with the
simpler method.

--
Rich Webb Norfolk, VA

 

[KevinR]

On Sun, 5 Sep 2004 16:12:27 -0400, "Rodney Kelp"
<Rodneykelp605@hotmail.com> wrote:

Maybe this is off topic but does anybody know how you convert the gps
position coordinace to distance? For instance If I am currently at
44 degrees 18 minutes 35.3 seconds lattitude and 69 46 52.4 longtitude and
I move to 44 18 35.3 by 69 46 54.0 how many feet have I moved easterly? I
can't seem to find any conversion tables that convert degrees, minutes,
seconds to feet. Am I expecting too much?
My GPS receiver will give me coordinance and speed in miles per hour and
direction but not the distance traveled. What's up with that?
I'm trrying to measure some acerage. I feel like I am going to feel really
stupid when someone tells me.



---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.745 / Virus Database: 497 - Release Date: 8/27/2004

You just use pythagoras.
Imagine a graph with an X and Y axis and two points on that graph
you'd construct a right angled triangle with one side parralel to the
x axis, another side parralel to the y axis and the hypoteneuse
joining the two points in question.

All you need to do now are convert the results in to feet.

The equator is split in to 360 degrees, each one of these degrees is
split in to 60 minutes and each minute in to 60 seconds
All you need to find out is how many feet is the circumference of the
earth.

Kevin R

 

[Robert C Monsen]

"BruceW..1" <sorry@noDirectEmail.com> wrote in message
news:rfO_c.14373$Y94.529@newssvr33.news.prodigy.com...

I'd like to power a 1-watt Luxeon Star
http://www.lumileds.com/products/family.cfm?familyId=2
with two AA batteries.

And I'd like to be able to dim the light. I've found that the
Luxeon Star puts out useable light down to 50mA, or up to about 350
mA.

This is for a headlamp to be used for camping and backpacking. Most
manufacturers of these headlamps use 3 batteries and a voltage
dropping resistor. IMHO, this is pretty cheesy and besides I'd like
to mod one of my existing AA headlamps.

Actually I'd like to make it run off of a single AA battery because
I'd rarely use full brightness.

Has Maxim come out with any new IC'c in the last year that might be
right for the job? I just ran across this, don't know what's
inside, but it doesn't dim:
http://www.luxeonstar.com/item.php?id=415&link_str=89&partno=02009A

I'm no electronics expert but I'm smarter than the average bear in
this respect and I can solder.

Can anyone recommend a circuit?

Thanks for your help.

Build a switcher. There are lots of circuits available. Here is one:

(View with courier font)

VCC = .8 to 3V
,---o---------------------.
| | |
.-. | C|
470R| |<-' C| L1
p1 | | C|
'-' |
| ___ || | D2
o--|___|-----o------||----o-->|--o---------,
| R1 | || | | |
| | C1 | | |
| | |/c | |
o------------|----------| Q2 | |
| | |> | .----'----.
| | | | | |
c\| | | --- | Luxon |
Q1 |----------o | C2 --- | Star |
<| | | | '----.----'
| - D1 | | |
| ^ | | |
| | | | |
'------------o------------o------o---------'
Ground

C1 = 220pF
C2 = 100uF electrolytic
R1 = 10k
Q1,Q2 = 2N4401
D1 = 1N4001
D2 = Schottky Diode
L1 = 33uH High Q inductor, at least 1A rating.

Put a 100 ohm resistor where your Luxon goes
Then, adjust voltage to minimum value before putting on star

You might want to use a power transistor for Q2. This circuit puts
more than rated current across it

created by Andy´s ASCII-Circuit v1.25.250804 www.tech-chat.de

Its a simple boost switcher, based on a two transistor oscillator. The
input voltage should be less than the forward voltage of the luxon +
Schottky, or it won't oscillate, and the luxon and inductor will fry.

I'm not sure it'll get all the way up to 350mA.

Regards,
Bob Monsen

 

[Spork]

http://www.candlepowerforums.com

has a infinite amount of information on flashlights and led's

"BruceW..1" <sorry@noDirectEmail.com> wrote in message
news:rfO_c.14373$Y94.529@newssvr33.news.prodigy.com...

I'd like to power a 1-watt Luxeon Star
http://www.lumileds.com/products/family.cfm?familyId=2
with two AA batteries.

And I'd like to be able to dim the light. I've found that the Luxeon
Star puts out useable light down to 50mA, or up to about 350 mA.

This is for a headlamp to be used for camping and backpacking. Most
manufacturers of these headlamps use 3 batteries and a voltage dropping
resistor. IMHO, this is pretty cheesy and besides I'd like to mod one
of my existing AA headlamps.

Actually I'd like to make it run off of a single AA battery because I'd
rarely use full brightness.

Has Maxim come out with any new IC'c in the last year that might be
right for the job? I just ran across this, don't know what's inside,
but it doesn't dim:
http://www.luxeonstar.com/item.php?id=415&link_str=89&partno=02009A

I'm no electronics expert but I'm smarter than the average bear in this
respect and I can solder.

Can anyone recommend a circuit?

Thanks for your help.