Driver to drive?

[John Popelish]

"S. hashem Aref" wrote:

thanks,
When I run it with Vr=5v and illuminated it with laser diode @1550nm
and power=1.5mw I saw a very low voltage in output of load resistance
(RL=100 ohm) that voltage was about .04mv.
If you want to look at my circuit I can attach for you.

If you have a silicon APD, it is almost completely transparent to 1550
nm. You will need an indium gallium arsenide (InGaAs) oe germanium or
other narrow band gap material to detect 1550.

--
John Popelish

 

[Ken Smith]

In article <0KLad.3608$j15.3033@trnddc07>,
Rich Grise <null@example.net> wrote:
[...]

But doesn't the multiplication of the two phase-shifted waves automagically
do that? i.e., the RMS value of the product (which is still a sine wave,
on a phase of its own, and smaller) will be the True Power, equal to
RMS volts * RMS amps * Power factor?

No, you don't want to take the RMS value of the product. You want to
average to product. The product of the current and voltage will have two
components. It will have a DC value equal to the average power and a sine
wave at twice the frequency. This sine wave at twice the frequency, you
want to ingore. The RMs would include it in the answer.


--
--
kensmith@rahul.net forging knowledge

 

[Ken Smith]

In article <1097549488.295263@ftpsrv1>,
Country Loon <fitlikemin@mearns.fairmers.co.uk> wrote:
[...]

RMS watts? Is there such a thing? Well there is average power and
instantaneous power but rms power is back to the old chestnut of Hi-Fi buffs
that have no engineering degree!

You can calculate the RMS power but the result isn't very useful. You
can just square all the values average the squares and squareroot the
result. While you are at it, you could figure the average tangent power.

--
--
kensmith@rahul.net forging knowledge

 

[colin]

"vijayamurugan.P" <netizen@outgun.com> wrote in message
news:1097575265.742912.257760@f14g2000cwb.googlegroups.com...

good evening

i wish to simulate a pwm
My waveforms are
1. sine wave @ 50 Hz 16 v
2.Carrier wave - Triangular wave 40v peak to peak.

i have to implement pwm using It.
i tried using 741 Opamp.but it misfires @ several instances
Can Anybody suggest me a better circuit
Thanks in Advance

vijay

if it 'misfires' sounds like the control voltage is going outside the range
of the sawtooth waveform.

Colin =^.^=

 

[Joerg]

Hi Rich,

What???!!!!???? A 555????? We don' need no steeenkeeeng 555!


To be honest, I have never really used one in a design for a customer

and if I ever did it would only be the CMOS version. Whenever I needed
timing I used CD chips, usually Schmitts. If you take a hex chip that
gives you a timing capability for a silicon cost share of under 2 cents.

Long timers are usually better done using dividers. After all, the cost
impact of a polyester cap or larger varieties in other technologies is
nothing to be sneezed at.

Regards, Joerg

http://www.analogconsultants.com

 

[Joerg]

Hi Terry,

Excellent advice. When stuff goes past the one minute marker these 4000
logic choices are clearly better than some RC combination on a one-shot.


Not for the application and precision requested by the OP. Quite
unnecessary. The 555 itself is capable of 1% accuracy (2 secs in 3
mins). With a modern low-leakage electrolytic as timing capacitor, and
reasonably careful construction, you could expect close to that even
for monostable or astable periods of the order of an hour.


For a one-up project and in a home environment with fairly constant

temperature and humidity, maybe. But when you look at the cost of low
leakage electrolytics the picture can change for a commercial product.
Also, ideally you do not want trim pots and I believe it is nearly
impossible to obtain an electrolytic under 5% tolerance at reasonable
cost. Even with polyester that is a challenge as they often cost more
than two resonators would. I guess that's why someone came up with the 4060.

Back in my days at the university one of our professors used to joke
that the quality of a digital designer is inversely proportional to the
number of one-shots he or she uses. Now I don't quite agree with that
and I use them a lot myself, even though they will be "home made" rather
than a 555 or HC123. It's just that the cost picture changes with longer
timings and cost is usually the predominant factor in a commercial design.

Regards, Joerg

http://www.analogconsultants.com

 

[Rolavine]

From: kensmith@green.rahul.net

I doubt that China has used threats. They tend to end the discussion. A
warning that the logical result of an armed N. Korea would be a re-armed
and militant Japan might have some sway.

I think the best would be for Kim to have a little accident when in China
to talk to them.

Yes, this would show the Chinese at least have managed a level of enlightenment

in their foreign policy that seems beyond us. Perhaps a heart attack after
eating some tainted General Tso's Shrimp? Quickly prosecute and execute a N.
Korean cook. Maybe we should have let the Chinese do Saddam, now that would
have really paid.

 

[Rolavine]

In Azimov's book "The Gods Themselves" we find another universe coexisting with
ours in another dimension, and this other universe is based on antimater, so
for energy they make some pipes and we pipe them packaged electrons and they
pipe us packaged positrons.

Kind of gives new meaning to the term blister pack though.

Rocky

 

[Dbowey]

boki posted:

<< dbowey@aol.com (Dbowey) wrote in message
news:<20041012011921.29600.00002158@mb-m29.aol.com>...

Why not?

RF is expensive.

Baseband much cheaper, isn't it?

For home device control, the funtion is the same.
Subjective terms like expensive and cheap are subject to broad interpretation.


An RF link with an Ethernet interface may have the same price as an RF link
with an analog or digital baseband interface.

It appears to me that you may be using "baseband" to mean a "metallic
connection" (cable such as Cat 5). In that case, where two equipments are in
easy connection range of a cable, Cat 5 is certainly less expensive than an RF
link. But I recently set up a wireless system for a grand daughter in her home
because it would have been difficult to run cable. Although the equipment cost
more than a piece of cable, It cost less than the value of time, whether I did
the job or farmed it out.

Also, I enjoy the freedom of wireless - I can be anywhere in the house or
outside without trailing a cable. That has a value making it cheaper than a
metallic connection.

Don

 

[Rene Tschaggelar]

meg wrote:

hi there,
i want to design a cmos amplifier with voltage gain of 0.5..
any guidance will be useful

And the output current ?
what frequency range were you thinking at ?

Rene
--
Ing.Buero R.Tschaggelar - http://www.ibrtses.com
& commercial newsgroups - http://www.talkto.net

 

[Rene Tschaggelar]

boki wrote:

Dear All,
These days I try to implement some baseband remote control, I
was feeling that is possible to complete control home devices within
baseband communications,


Why RF? for distance?

WLAN :
It is considered a necessity to be able to download the SPAM
everywhere all the time. Unwary system administrators appreciate
when strangers occasionally use their private network for
internet access.

Why Bluetooh? for handshake?

Bluetooth was invented to occupy the 2.5GHz band with trivialities,
but at the same time all electronics devices have to withstand
these frequencies as well as not radiate them. This can put the
able designers at an advantage. Plus every other designer had to
purchase a new spectrum analyzer to do the measurements.

Luckily, we can just rise the prices to cover the expenses.


Rene
--
Ing.Buero R.Tschaggelar - http://www.ibrtses.com
& commercial newsgroups - http://www.talkto.net

 

[John Larkin]

On 12 Oct 2004 00:24:26 -0700, robin.pain@tesco.net
(robin.pain@tesco.net) wrote:

"Left hand down a bit number one. What's that to starboard?"

"It's the missing DLL captain."

"Hold her steady, steady... Fire!"

"I can't sir, it says 'Windaz has detected you are too pissed to
operate machinery' Sir."

"What! lemme see! Blimey they've installed "Windaz-too-thoosand (c)",
the student version for the North of England... none of us will be
able to use it, I told them to get the full home version."

Cheers
Robin Pain

Windows is good for the tugboat industry:

http://feed.proteinos.com/001229.html


John

 

[Peter]

"Ryan Ashline" <ashline@yahoo.com> wrote in message
news:54109d7d.0410110926.5df71b07@posting.google.com...

I am looking for a 12 volt timer or looking to build one. What I
would like it to do is when powered wait for approx 3 mins (doesnt
have to be close 15 sec or so +- would be ok) Then trigger a light I
have for 2-3 secs shut off then repeat the entire sequence again. 3
mins off 3 secs on. Would some please point me in the right
direction?

Thanks for your time

Ryan Ashline

A little program like this into a PIC would do the trick.

main: low 0
wait 180
high 0
wait 3
goto main

"wait" counts in seconds, Just add a transistor or a relay to drive the
load.

If you are in Australia I could supply the complete unit you are after,
including the programmed chip. I have about 100 of these PCB's hanging
around. 12V ac/dc in, same out, max load 5A.

Just a thought.

 

[Dirk Bruere at Neopax]

Scott Stephens wrote:

Dirk Bruere at Neopax wrote:

The US is going to a position already attained in Britain.
That is, the govt has found that it's far easier passing laws to
constrain the behaviour of law abiding citizens than it is to do the
same for criminals (or even catch them).


What does this say for the mindset of the politicians? The citizens are
the "enemy", the people are the problem, not the solution.

And government is the problem of the people!

No, the people are the problem because they welcome it.

--
Dirk

The Consensus:-
The political party for the new millenium
http://www.theconsensus.org

 

[Rich Grise]

On Tuesday 12 October 2004 06:50 am, Tam/WB2TT did deign to grace us with
the following:

How about a compromise desig,:
1. Build an oscillator with a period of 3 seconds. Easily doable with
standard component. ( 1 ufd mylar cap + few megaohm)
2. Feed the output to a 6 bit counter.
3. Connect the reset lead of the counter to an RC network so it powers up
000000.
4. Detect the 111111 state to turn on the light.
5. This gives 192 seconds OFF, 3 seconds ON.

Hey, I posted this circuit yesterday, ASCII art and all! Where did my

post go?

Thanks,
Rich

 

[Rich Grise]

On Tuesday 12 October 2004 06:50 am, Tam/WB2TT did deign to grace us with
the following:

How about a compromise desig,:
1. Build an oscillator with a period of 3 seconds. Easily doable with
standard component. ( 1 ufd mylar cap + few megaohm)
2. Feed the output to a 6 bit counter.
3. Connect the reset lead of the counter to an RC network so it powers up
000000.
4. Detect the 111111 state to turn on the light.
5. This gives 192 seconds OFF, 3 seconds ON.

Right here: <lxGad.3480$Rp4.2607@trnddc01>

Cheers!
Rich

 

[Dave VanHorn]

Serial data as in RS-232, or Serial data as in clocked serial Interface?
You can do the AVR mega series with 232, IF they are preloaded with a
bootloader.
I have a printer design done this way, the comms AVR programs three other
processors, or itself, all through the printer's serial/USB port.
--
KC6ETE Dave's Engineering Page, www.dvanhorn.org
Microcontroller Consultant, specializing in Atmel AVR

 

[Dirk Bruere at Neopax]

john jardine wrote:

robin.pain@tesco.net> wrote in message
news:bd24a397.0410121101.1c1469de@posting.google.com...

"colin" <no.spam.for.me@ntlworld.com> wrote in message

news:<GhSad.1102$y04.76@newsfe5-win.ntli.net>...

robin.pain@tesco.net> wrote in message
news:bd24a397.0410112324.42477888@posting.google.com...

"Left hand down a bit number one. What's that to starboard?"

"It's the missing DLL captain."

"Hold her steady, steady... Fire!"

"I can't sir, it says 'Windaz has detected you are too pissed to
operate machinery' Sir."

"What! lemme see! Blimey they've installed "Windaz-too-thoosand (c)",
the student version for the North of England... none of us will be
able to use it, I told them to get the full home version."


Please tell me theres no truth to this at all?

"never a truer word has been spoken in jest"

Colin =^.^=

http://www.theregister.co.uk/2004/09/06/ams_goes_windows_for_warships/

http://members.lycos.co.uk/mriainwilson/humour/


Those defense procurement civil servants haven't a f****ng clue. They
supplied shit military equipment in WW1 and WW11 and they're still at it
now.
To a man, all ex public school boys and old school tie. All arts graduates.
All closeted in comfy Whitehall offices. All waiting to stroll across to
board positions in the arms companies they're supposed to be dealing with on
our behalf.
No one oversees them. No one can bring them to account. No one of them will
ever blow a whistle. All of them incompetant and corrupt as hell.
They issue our troops with the (still) f****ng useless SA80 rifle. Clothe
'em in inferior materials. Give 'em second rate boots to wear. Fail to issue
'em with body armour yet allow massive cost overruns on UK produced war
materiel that could be much better and cheaper sourced elsewhere.

Windaz in subs and naval vessels?. Jesus f****ng wept.
The whole of the procurement executive need their arses smacking. Engineers
putting in charge and a long term, commons investigative commitee setting
up.

Won't happen.
If MI5 was really here to protect the people they'd spend a significant amount
of time 'spying' on the defence firms. Not at board level, but canteen level.

When I was a young engineer GEC had been awarded the Nimrod project - a Brit AWACS.

Almost from the start the engineering grapevine told us that it would never work
because fundamentally wrong decisions had been taken at the outset. Six years
and a Ł1billon later (back when that was a lot of money) GEC acknowledged
failure. Didn't matter to them, though, because they were laughing all the way
to the bank.

Jim Prior, the minister in charge of that fiasco on the govt end of things later
became the chairman of GEC after he was kicked out.

--
Dirk

The Consensus:-
The political party for the new millenium
http://www.theconsensus.org

 

[Harry Dellamano]

"Steve Roberts" <osteven@akrobiz.com> wrote in message
news:86dacd49.0410121358.5a456fc7@posting.google.com...

Anybody have a old Cherry Semi data sheet for cs322/cs324?
I'm looking for the cS324 data in a 8 pin dip, its a hysteretic PWM
controller used in some power supplies for argon lasers, I have about
6 units to rebuild but the chip is obsolete and Cherry Semi has been
sold to On-Semi.

Thanks,
Steve Roberts

Steve,
I have 6 unused CS322 you can have.

Parts are cheap, labor is expensive, right J.T. (Mr.$200 USD/hr).

Harry

 

[John Larkin]

On Tue, 12 Oct 2004 17:06:20 -0700, "Joel Kolstad"
<JKolstad71HatesSpam@Yahoo.Com> wrote:

I'm all for using Linux, but I think a lot of these reports are overblown.
Somehow people seemed shocked that 'Windows has failure modes' and 'Windows
has known bugs.' Well, duh! So do all UNIXes out there. If anything, I
think you can make a strong argument that Windows could be MORE secure
simply because it's been SO WELL TESTED by ever script kiddie
would-be-hacker out there. Microsoft is really in a losing position here:
If they simply fix security holes and don't mention them and someone finds
out as much later, they're accused of being secretive. If they admit to
their security holes and immediately patch them, they're accused of having a
buggy OS.

Except that Windows is hundreds of million of lines of crap code. Any
decent RTOS or OS or time-sharing operating system circa 1980 would
run for months without a reboot. Linux has had something like 20
security holes so far, while Windows is in the thousands.

Microsoft is certainly not in a losing position. They have tens
billions in cash and make billions a year more by selling garbage that
needs to be upgraded at great expense forever, and by stealing
everybody's markets under the name of "innovation", and by crushing
all their competition illegally and ruthlessly.

Microsoft products are garbage, and they can't code.

John