Chip with simple program for Toy

[Watson A.Name - 'Watt Sun]

In article <3F06C992.734E02F1@charter.net>, dressel1@charter.net
mentioned...

I suppose I can see the need with the flashlights, being that the alternative is more
LEDs (more costly upfront / bulkier).

I agree that based on usage, if I can get 25,000 hours of use out of them, it'll be
more than adequate. Very likely that by the time the LEDs burn out, some new and
improved light will be out anyway.

From my own personal experience, by the time the LEDs burn out, I will
have lost the light and had to replace it with another. Last week I
lost one of my regular mini Maglites, so I'm only out ten bucks. Glad
it wasn't the one with the LED conversion, 'cause that cost another
$30. :-/

"Watson A.Name - 'Watt Sun'" wrote:

In article <3F0651DC.5FA9A926@charter.net>, dressel1@charter.net
mentioned...
I figured that was the reason. I did put a 10 ohm resistor in series with the
3.6v source and the LED, but it still appeared brighter (of course, that is based
on my eyes, which are far from perfect).

For the series of 5, I figure I can get by with a 430ohm resistor (maybe a 390ohm
if necessary for brightness, though that will bring the current to around
21-22mA). Does anyone have a quantitative feel for how the higher current will
affect LED life? Based on the "perfect" scenario, they should last around
50,000-100,000 hours (these are probably standard numbers). I won't need them on
full time, so if I could get a quarter of that, it would more than suffice. Heat
dissipation should not be a problem.

For the white LEDs, I use a 33 ohm resistor for 4.5V = three AA cells.
That gives about 30 mA, and with fresh batteries, it's probably closer
to 40 mA. The lifetime may be shorter by 50%, but I figure that it'll
take a lifetime to put that many hours on them, being they get used a
few hours a year. So it really doesn't matter. And the tradeoff of
increased light output is well worth it.

I've read that some flashlight makers run their LEDs at 2 or 3x the
max, or something like 50 to 90 mA.

later,
Kevin

"Watson A.Name - 'Watt Sun'" wrote:

In article <3F06264D.4BB9FCE5@charter.net>, dressel1@charter.net
mentioned...

[snip]

If you put the LED across the 3.6V, you should *still* put a current
limiting resistor in series with it. If you don't, then the battery
is probably pushing much more than the 30 mA maximum thru the LED.
Watch out for the overly hot LED.

Thanks,
Kevin

[snip]

--
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[John Jardine]

Patrick Leonard <transactoid@rogers.com> wrote in message
news:iHtNa.58918$a51.44869@news02.bloor.is.net.cable.rogers.com...

I'm trying to figure out if its possible to build a super simple signal
generator uisng only one transistor and no other ICs.

The idea being you charge up a capacitor through a resistor then when the
cap is at an adequate potential, its voltage will turn on a transistor.
The
transistor being on simply completes a circuit allowing the cap to
discharge. Whence the cap has discharged, the transistor turns off, and
the
cap charges again. Repeat......

This seems logical to me, yet I cannot design a circuit that works this
way....it always seems like I'm missing something. Am I just not being
"clever" enough, or is such a circuit indeed impossible?

Thanks
Patrick

Nope, it won't work!.

A tranny doesn't have a true switching action, it's linear from full off to
full on.
It will always be happy to self stabilise at a balance point, where the
tranny is part 'on' and the cap' is still being slightly charged. Need at
least two transistors to do this job.
regards
john

 

[John Fields]

On Sat, 05 Jul 2003 07:12:13 GMT, rampart@easynews.com (G.T.W.) wrote:

Did you add the capacitor after the bridge rectifier?

Otherwise, the 4 diodes provide the full wave positive alternations,
but are still largely 'ripple' voltage. The filtering provide by
capacitors smooths the ripple so that your average DC voltage is more
consistant.
Heavy loading will decrease the cap's filtering effectiveness (unless
you increase the value of the cap).

---
Wrong.

You either went to the link and didn't know the bridge was shown
incorrectly connected or you didn't go to the link at all, in which case
you're still wrong.
--
John Fields
Professional circuit designer
http://austininstruments.com

 

[Henry Kolesnik]

GE used to recommend NiCd be stored discharged and I've notice most new
stuff is shipped with the batteries requiring at least 24 hours, so I guess
discharged is best storge method. Cool and dry also.
hank wd5jfr
"a.n" <recycle@btinternet.com> wrote in message
news:bdqk5a$24f$1@titan.btinternet.com...

Hello everyone,
Question about rechargable batteries:
What is the best way to store AA rechargable batteries. Is it to simply
keep them charged and then discharge them and recharge them after
about 6 month, or is it better to store them discharged and then charge
them
and discharge them again after 6 months. Would it make any difference
if the batteries are nicad, ni-mh, or ultra capacity ni-mh?

 

[John Larkin]

On Sat, 05 Jul 2003 05:51:10 GMT, "Patrick Leonard"
<transactoid@rogers.com> wrote:

I'm trying to figure out if its possible to build a super simple signal
generator uisng only one transistor and no other ICs.

The idea being you charge up a capacitor through a resistor then when the
cap is at an adequate potential, its voltage will turn on a transistor. The
transistor being on simply completes a circuit allowing the cap to
discharge. Whence the cap has discharged, the transistor turns off, and the
cap charges again. Repeat......

What actually happens in most transistor-r-c circuits is a stable
equilibrium without oscillation.

This seems logical to me, yet I cannot design a circuit that works this
way....it always seems like I'm missing something. Am I just not being
"clever" enough, or is such a circuit indeed impossible?

Thanks
Patrick

If a transistor is operating normally, I'd say it's impossible to make
an oscillator with one transistor, one capacitor, and one resistor.
Special cases are...

1. Many transistors oscillate, typically at hundreds of MHz, if biased
right (or maybe wrong); but it's not your RC that sets the frequency.
You can make a nice RF oscillator from a 2N2219 and one resistor.

2. Avalanche mode: leave the base open and charge the collector
through the r-c, with a high-voltage (100-500v depending on the
device) supply; you may get a nice sawtooth at the collector.

One transistor and three each r,c makes a phase-shift oscillator.

John

 

[John Popelish]

Patrick Leonard wrote:

I'm trying to figure out if its possible to build a super simple signal
generator uisng only one transistor and no other ICs.

The idea being you charge up a capacitor through a resistor then when the
cap is at an adequate potential, its voltage will turn on a transistor. The
transistor being on simply completes a circuit allowing the cap to
discharge. Whence the cap has discharged, the transistor turns off, and the
cap charges again. Repeat......

This seems logical to me, yet I cannot design a circuit that works this
way....it always seems like I'm missing something. Am I just not being
"clever" enough, or is such a circuit indeed impossible?

Thanks
Patrick

I don't think that the oscillator you describe is possible. There are
several steps in the oscillation process that you are missing. What
causes the transistor to suddenly switch on when the cap reaches some
arbitrary voltage, but stay on while the voltage falls below that till
some other arbitrary voltage is reached?

The closes thing I can think of is a phase shift oscillator (which
produces a sine wave rather than a pulse or saw tooth waveform. And
it takes a few more resistors and capacitors, but can run on a single
transistor.
http://www.tpub.com/neets/book9/35e.htm

--
John Popelish

 

[nick]

i141802596@yahoo.com (nick) wrote in message news:<4f981f90.0307041718.22a99a5a@posting.google.com>...

1.if i want to make a simple remote controller and reveiver ,e.g. when
i pressing button A from the controller,then LED A will turn on in the
receiver side,i don't want the use IR TX &RX,so i want to use RF, but
i have no idea to make it,so anyone can give me a simple diagram,or
give me some web sites about the RF.

2.i have found some diagrams about them ,i think they are very
complex for me ,in the diagrams a component called inductor,what is
this? , How to use it?

3.if i want to make a simple bug,is it principle like the remote
contoller? i have found some web sites only teach how to make the
transmitter,they use radio to work as the receiver, that means anyone
turn their radio to the same band ,then they also can receive the
singles?

any one ? can help me?

 

[G.T.W.]

On Sat, 05 Jul 2003 09:33:37 -0500, John Fields
<jfields@austininstruments.com> wrote:

On Sat, 05 Jul 2003 07:12:13 GMT, rampart@easynews.com (G.T.W.) wrote:

Did you add the capacitor after the bridge rectifier?

Otherwise, the 4 diodes provide the full wave positive alternations,
but are still largely 'ripple' voltage. The filtering provide by
capacitors smooths the ripple so that your average DC voltage is more
consistant.
Heavy loading will decrease the cap's filtering effectiveness (unless
you increase the value of the cap).

---
Wrong.

You either went to the link and didn't know the bridge was shown
incorrectly connected or you didn't go to the link at all, in which case
you're still wrong.

About what? I can say that you are wrong all day long, but without
proof, you are barking up the wrong vagina.

Did you bother to read the original post? See the part where the
author mentions the 4 diodes? He doesn't indicate if he tried to add
filtering. He only talks about rectification, which your 'expert' ass
should know is only a piece of the process.

Remember the numbers for average DC with a bridge rectifier? .636 x
Vmax is mostly ripple. Everyone knows that large ripple is iill
suited for digital processors (remember the embedded referance?)

Oh wait, you are too much of an expert to know this, aren't you?

Oh, and Mr. Expert, filtering DOES smooth out the ripple, raising the
average DC level.

also Mr. Expert, the effectiveness of filtering is reduced with heavy
loading on the circuit. Increasing the caps value will help.
This is not to say it is the only solution to loading, just one way.

so don't get your crusties in a bunch because I took the time to read
what the author WROTE. I don't give a fuck about a picture, because
he did not say he tried to construct the whole circuit. He only said
the DIODES WERE SIMILAR to the circuit at such and such link.

But I am glad you have the eagle eye. While you are trash talking
here, why don't you also contact the web site and let them know of the
mistake? I'll bet they wont' even bother with a response to such a
silver tongued devil like you.

Get a fucking job, and try to learn to read, dickhead.

--
John Fields
Professional circuit designer
http://austininstruments.com

 

[Rich Grise]

"Patrick Leonard" <transactoid@rogers.com> wrote in message news:<iHtNa.58918$a51.44869@news02.bloor.is.net.cable.rogers.com>...

I'm trying to figure out if its possible to build a super simple signal
generator uisng only one transistor and no other ICs.

The idea being you charge up a capacitor through a resistor then when the
cap is at an adequate potential, its voltage will turn on a transistor. The
transistor being on simply completes a circuit allowing the cap to
discharge. Whence the cap has discharged, the transistor turns off, and the
cap charges again. Repeat......

This seems logical to me, yet I cannot design a circuit that works this
way....it always seems like I'm missing something. Am I just not being
"clever" enough, or is such a circuit indeed impossible?

Thanks
Patrick

I've seen several responses from people who don't know how to build
a one-transistor oscillator. You need a few resistors and capacitors,
and maybe an inductor or two, depending on what frequency range you're
looking for, but I got 26 (!) hits on "one-transistor oscillator" at
http://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=+%22one-transistor+oscillator%22

(you might have to copy/paste that, or you could just go to
http://www.google.com and enter "one-transistor oscillator" with
the quotes.)

(this one has a bridged-T:
http://www.geocities.com/SiliconValley/2775/mcwosc1.html )

Good Luck!
Rich

 

[G.T.W.]

On 5 Jul 2003 12:39:17 -0700, richardgrise@yahoo.com (Rich Grise)
wrote:

"Patrick Leonard" <transactoid@rogers.com> wrote in message news:<iHtNa.58918$a51.44869@news02.bloor.is.net.cable.rogers.com>...
I'm trying to figure out if its possible to build a super simple signal
generator uisng only one transistor and no other ICs.

The idea being you charge up a capacitor through a resistor then when the
cap is at an adequate potential, its voltage will turn on a transistor. The
transistor being on simply completes a circuit allowing the cap to
discharge. Whence the cap has discharged, the transistor turns off, and the
cap charges again. Repeat......

This seems logical to me, yet I cannot design a circuit that works this
way....it always seems like I'm missing something. Am I just not being
"clever" enough, or is such a circuit indeed impossible?

Thanks
Patrick


I've seen several responses from people who don't know how to build
a one-transistor oscillator.

You are right. I don't know to build one either.
but I do know how to make one with a schmitt trigger and 2 other
devices.

You need a few resistors and capacitors,
and maybe an inductor or two, depending on what frequency range you're
looking for,

Well, then this isn't what the author was asking for either, so now I
don't feel so bad about mentioning an alternative that did meet the
minumum number of pieces.

but I got 26 (!) hits on "one-transistor oscillator" at
http://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=+%22one-transistor+oscillator%22

(you might have to copy/paste that, or you could just go to
http://www.google.com and enter "one-transistor oscillator" with
the quotes.)

(this one has a bridged-T:
http://www.geocities.com/SiliconValley/2775/mcwosc1.html )

Good Luck!
Rich

 

[Roger Johansson]

rampart@easynews.com (G.T.W.) wrote:

What part of "...only one transistor and no other ICs" did you have
trouble with?

I apologize.

You shouldn't apologize. You are the only one in this thread who have
given constructive advice to a beginner, all the others are just
bitching about theoretical details.

Well, Grise just posted a constructive message too, but not as good an
advice as you gave.

Not knowing how to produce an oscillator with a
standalone transistor, I considered a single IC, the size of a postage
stamp, as a viable alternative. This is the schmitt trigger.

The number of parts is still the same.

1. transistor, resistor, and cap
or
2. chip, resistor, and cap

a) A transistor still requires bias voltage to conduct,
b) schmitt trigger requires 5 volts to operate.

Additionaly, the costs for a standalone transistor (for example, a
2N2222A) is just as inexpensive as the 7414, under a dollar at my
electronics shop. Since I do not know how the author is going to bias
the transistor (voltage divider or whatever), power for an IC is even
simpler.

It is possible to create an oscillator with one transistor, but then
he needs to use a transformer, or a couple of capacitors, and it is no
beginner project in terms of understanding how it works.

You took the line of thought from Leonard and made it useful, I think
that is worth more than to slavishly follow the specifications of the
person who asked the question, who obviously do not have knowledge
enough to make such exact specifications.

I have seen hundreds of examples of the same behaviour here during the
years, some people solve problems like they were still in school,
following exactly the specifications of the person who asked the
question instead of seeing his ideas for what they are worth and help
him develop his ideas at his own level of understanding.

--
Roger J.

 

[John Larkin]

On Sat, 05 Jul 2003 22:12:44 +0200, Roger Johansson <no-email@home.se>
wrote:

You shouldn't apologize. You are the only one in this thread who have
given constructive advice to a beginner, all the others are just
bitching about theoretical details.

....

I have seen hundreds of examples of the same behaviour here during the
years, some people solve problems like they were still in school,
following exactly the specifications of the person who asked the
question instead of seeing his ideas for what they are worth and help
him develop his ideas at his own level of understanding.

I disagree. The OP could certainly google "transistor oscillator" and
get hundreds of circuits. He was proposing using one transistor, one
capacitor, and one resistor, under the assumption that transistors
have a regenerative behavior, which they don't. Several of the posters
(including YHS) pointed this out and suggested alternate ways to get a
single transistor to oscillate.

Some degree of precision should be allowed here, I should think. These
"theoretical details" do matter.

John

 

[Roger Johansson]

John Larkin <jjlarkin@highlandSNIPtechTHISnologyPLEASE.com> wrote:

I disagree. The OP could certainly google "transistor oscillator" and
get hundreds of circuits. He was proposing using one transistor, one
capacitor, and one resistor, under the assumption that transistors
have a regenerative behavior, which they don't.

G.T.W. told him what kind of device he could use to get that
behaviour.

Several of the posters
(including YHS) pointed this out and suggested alternate ways to get a
single transistor to oscillate.

Yes, but they did not care about how Leonard was thinking and help him
find a device which works like he thought it could work.
His line of thought was valuable, and should have been taken care of
like G.T.W. did.

Some degree of precision should be allowed here, I should think. These
"theoretical details" do matter.

It is more important to cultivate the useful line of thought from the
person who asks a question, as I see it.

But what I really reacted too was Kevins way of forcing G.T.W. into a
corner and making him apologize, that kind of aggressive behaviour is
not suitable, especially not in a beginners newsgroup.

Kevin is a bitch, who likes to show off his superior knowledge in the
electronics field, and his talent for a friendly and constructive
cooperation with beginners is close to non-existent.

Others may have assumed that he had only a transistor to play with and
gave advice about a completely different construction, okay, that is
also useful, but as I see it not as good as G.T.W.:s reply.

--
Roger J.

 

[A E]

Patrick Leonard wrote:

I'm trying to figure out if its possible to build a super simple signal
generator uisng only one transistor and no other ICs.

Sine waves are signals, so yes.

The idea being you charge up a capacitor through a resistor then when the
cap is at an adequate potential, its voltage will turn on a transistor. The
transistor being on simply completes a circuit allowing the cap to
discharge. Whence the cap has discharged, the transistor turns off, and the
cap charges again. Repeat......

Relaxation oscillator, eh? That requires some non-linear behavior. You won't get
that out of one BJT.

This seems logical to me, yet I cannot design a circuit that works this
way....it always seems like I'm missing something. Am I just not being
"clever" enough, or is such a circuit indeed impossible?

Even better, no transistor at all. Look for a tunnel diode circuit. Now, try to
find a tunnel diode....

Thanks
Patrick

 

[Bill Bowden]

i141802596@yahoo.com (nick) wrote in message news:<4f981f90.0307050926.17859593@posting.google.com>...

i141802596@yahoo.com (nick) wrote in message news:<4f981f90.0307041718.22a99a5a@posting.google.com>...
1.if i want to make a simple remote controller and reveiver ,e.g. when
i pressing button A from the controller,then LED A will turn on in the
receiver side,i don't want the use IR TX &RX,so i want to use RF, but
i have no idea to make it,so anyone can give me a simple diagram,or
give me some web sites about the RF.

2.i have found some diagrams about them ,i think they are very
complex for me ,in the diagrams a component called inductor,what is
this? , How to use it?

3.if i want to make a simple bug,is it principle like the remote
contoller? i have found some web sites only teach how to make the
transmitter,they use radio to work as the receiver, that means anyone
turn their radio to the same band ,then they also can receive the
singles?

any one ? can help me?

You can use an RF oscillator as a transmitter,
but it will be difficult to keep the frequency stable.
And the receiver is much more complicated, so that's
why a FM radio is usually used. Why don't you just
use a couple of those family band walkie talkies?
They transmit about a mile.

-Bill

 

[John Larkin]

On Sat, 05 Jul 2003 23:02:20 +0200, Roger Johansson <no-email@home.se>
wrote:

John Larkin <jjlarkin@highlandSNIPtechTHISnologyPLEASE.com> wrote:

I disagree. The OP could certainly google "transistor oscillator" and
get hundreds of circuits. He was proposing using one transistor, one
capacitor, and one resistor, under the assumption that transistors
have a regenerative behavior, which they don't.

G.T.W. told him what kind of device he could use to get that
behaviour.

OP had a misconception about the way a transistor acts, namely that
base drive "triggers" collector conduction or something like that. I
should think it important that he discover how transistors really
behave, as opposed to just giving up on understanding a transistor and
using an IC schmitt trigger to build an oscillator.

There are two paths to electronics:

1) theory: start with understanding fundamentals: voltage, current,
R-L-C properties, then simple active parts, and so on

2) cookbook: build circuits, based on handbooks, web pages, diagrams
of existing equipment, and modify them experimentally if required.

Either can be a path to an interesting hobby, but only 1) results in
any real understanding, or is a path to a professional career.

I agree that this is a "basics" group, so people with questions should
be guided towards answers in a friendly manner. I prefer to steer
people towards understanding fundamantals; others may prefer to just
say "no, that doesn't work: use a 555"

Someday I'd like to teach a course using only Rs, Cs, and CK722
transistors.

John

 

[Michael A. Terrell]

"G.T.W." wrote:

On Sat, 5 Jul 2003 08:32:56 +0100, "Kevin Aylward"
kevin@anasoft.co.uk> wrote:

G.T.W. wrote:
Your're on the right track. You can make an oscillator with one IC, a
resistor and a capacitor.

{snip}

What part of "...only one transistor and no other ICs" did you have
trouble with?

I apologize. Not knowing how to produce an oscillator with a
standalone transistor, I considered a single IC, the size of a postage
stamp, as a viable alternative. This is the schmitt trigger.

The number of parts is still the same.

1. transistor, resistor, and cap
or
2. chip, resistor, and cap

a) A transistor still requires bias voltage to conduct,
b) schmitt trigger requires 5 volts to operate.

Additionaly, the costs for a standalone transistor (for example, a
2N2222A) is just as inexpensive as the 7414, under a dollar at my
electronics shop. Since I do not know how the author is going to bias
the transistor (voltage divider or whatever), power for an IC is even
simpler.

I am sorry for screwing up this whole thread.

Ignore Kevin. He is an old pain in the ass who only hangs around to
bitch and to push his Spice software.

The only thing you might have done differently was preface your
answer with, "You can't do it with just the three parts, but you could
try this..."
--


Michael A. Terrell
Central Florida

 

[Michael A. Terrell]

Roger Johansson wrote:

Kevin is a bitch, who likes to show off his superior knowledge in the
electronics field, and his talent for a friendly and constructive
cooperation with beginners is close to non-existent.

--
Roger J.

Roger, Kevin is only here to push his Spice software. Remember all
his attacks on Mike, when he was on the electronics newsgroups answering
questions about the free Switchercad software? Rather than offer help,
he spent all his time ranting that only his GUI for Spice was usable,
and you had to be a moron to use anything else. A lot of people have
him kill filed for this. On the design groups he routinely attacks
people with years of practical design experience, rather that discuss
differences in design philosophies.
--


Michael A. Terrell
Central Florida

 

[Michael A. Terrell]

tempus fugit wrote:

Hey all;

I'm thinking of buying either an ESR meter or capacitance meter, but am not
sure which is more useful. I would be using it mostly for troubleshooting,
so I was thinking ESR meter, since it is my understanding that a cap is more
likely to fail or cause problems because of high ESR rather than incorrect
capacitance.

Any advice?

Thanks

Both have their uses. The ESR meter is good to quick check
Electrolytics, but you need a capacitance meter to check ceramic, film
and other smaller capacitors. If you are building with new parts I
would buy the capacitance meter first, but if you plan on using used
parts for projects, I would add the ESR meter.

I have the Dick Smith ESR meter, designed by Bob Parker, in
Australia.
--


Michael A. Terrell
Central Florida

 

[roma]

"Patrick Leonard" <transactoid@rogers.com> wrote in
news:iHtNa.58918$a51.44869@news02.bloor.is.net.cable.rogers.com:

I'm trying to figure out if its possible to build a super simple
signal generator uisng only one transistor and no other ICs.

The idea being you charge up a capacitor through a resistor then when
the cap is at an adequate potential, its voltage will turn on a
transistor. The transistor being on simply completes a circuit
allowing the cap to discharge. Whence the cap has discharged, the
transistor turns off, and the cap charges again. Repeat......

This seems logical to me, yet I cannot design a circuit that works
this way....it always seems like I'm missing something. Am I just not
being "clever" enough, or is such a circuit indeed impossible?

Thanks
Patrick

See cheapo oscillator page 23 http://members.shaw.ca/roma
roma