Chip with simple program for Toy

[Roger Johansson]

"royalmp2001" <royalmp2001@hotpop.com> wrote:

How do I add biasing .25V to the output of the 7555?

Put a big capacitor in series with the output. Now you have a new output
which is not locked in any way DC-wise.

Put two resistors in series between your positive and negative supply
lines, choose the resistor so that the DC voltage in the point between
the resistors is .25V.

Connect the DC-less output with the 0.25V DC "generator" you you built
from two resistors. The result is an output signal with a certain AC
signal, and a certain DC average level.

Both signals can be controlled separately from each other and are added
to each other at the output.


--
Roger J.

 

[peterken]

"Roger Johansson" <no-email@home.se> wrote in message
news:Xns95ED14DC06A4D86336@130.133.1.4...

"royalmp2001" <royalmp2001@hotpop.com> wrote:

How do I add biasing .25V to the output of the 7555?

Put a big capacitor in series with the output. Now you have a new output
which is not locked in any way DC-wise.

Put two resistors in series between your positive and negative supply
lines, choose the resistor so that the DC voltage in the point between
the resistors is .25V.

Connect the DC-less output with the 0.25V DC "generator" you you built
from two resistors. The result is an output signal with a certain AC
signal, and a certain DC average level.

Both signals can be controlled separately from each other and are added
to each other at the output.


--
Roger J.

that's one way, BUT dependant of supply level unless the voltage divider is
created using a V-reference

 

[Bob Masta]

On 28 Jan 2005 15:58:47 -0800, "royalmp2001" <royalmp2001@hotpop.com>
wrote:

The project is called a ZAPPER pioneered by Dr Hudda Clark and is a
pseudo-medical experimental device that supplies a 39KHz square wave
with 0.25V positive offset to two handhold electrodes, which the
patient holds for a certain duration.

The claim is that parasites, bacteria, molds, and viruses in the body
are killed by this operation.

Sorry, I can't let this go past.

This is quack medicine at its finest. I'll bet that it also cures
cancer and HIV, as well as neutralizing fat while you sleep.

Consider that the signal is going between the two hands,
ie right across the heart. Do you want to be responsible
for any unfortunate outcomes? Consider that this design
was "pioneered" by an obvious quack with little knowledge
of biology, let alone medicine. Not the sort of person to
trust with safety or health issues.

Best regards,


Bob Masta
dqatechATdaqartaDOTcom

D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com

 

[Scott Goss]

Here's a pic in case it helps...

Thanks, Scott

On Sat, 29 Jan 2005 06:56:13 GMT, Scott Goss
<scott.goss@earthlink.net> wrote:

I have a BYTEK S15-F Multiprogrammer, but cannot find a source for
manuals/software. Does anyone know where these can be downloaded, or
does anyone have originals they could copy for me? I'd really
appreciate it and I would be more than willing to paypal you a few
bucks for your trouble.

Please use scott.goss <at> earthlink.net if replying as I don't check
this group all the time.

Thanks, Scott

 

[Roger Johansson]

"peterken" <peter273@hotmail.com> wrote:

that's one way, BUT dependant of supply level unless the voltage
divider is created using a V-reference

Yes, of course the "DC generator" can be improved, if needed, through
lower resistors to give lower impedance, or by buffering it with an
opamp, or by creating a voltage which is better regulated, if needed,
etc..


--
Roger J.

 

[JeffM]

The project is called a ZAPPER pioneered by Dr Hudda Clark
and is a pseudo-medical experimental device
royalmp2001

This is quack medicine at its finest.
Bob Masta

It seems he's aware of that.
We can hope that it's royalmp2001's entry into the science fair
with the goal being to prove it's junk science.

OTOH, maybe he's an entrepreneur who's familiar with Barnum.

I google Dr. Dean Edell
and was surprized when this didn't send up flares.
http://www.google.com/search?&q=site%3Ahealthcentral.com+Hudda-Clark

 

[Anthony Fremont]

Rubicon wrote:

Hello,

I'm trying to make a 24kHz ultrasonic transmitter capable of sending
AM serial data to a receiver over a min 30ft range. I have no scope or
frequency counter (looking for a counter locally) and have managed to

Personally, I'd recommend getting a scope first. I use my ~20 year old
scope about 100 times as much as I use my frequency counter.

get it just-going on occasion over a couple of feet by using high
tolerance components and using an ultrasonic tone controlled switch
kitset as a tuning referance. I'd foolishly thought when I bought the
kit "What are the chances of there being 24kHz lurking about?" Pretty
good actually. Drop a tool on the garage floor, tap the workbench and
away she'd go. Lucky I didn't connect it to the main garage door!

Transmitter.
At present I have a 16F84A PIC sending serial out at T1200 (True
logic) to the reset pin of a 555 timer set for 24kHz. Its output goes
to a 4069 inverter that drives a transducer. The inverter is wired in
parallel, 180 degrees shifted for maximum output. My PIC programmer is
old and doesn't go beyond the 16F84A which is why I'm trying to do it
this way.

TX PIC----555 24kHz----INVERTER----TRANSDUCER

Why not just drive the transducer directly from the PIC? If you put the
transducer accross two output pins, you can develop 10V of drive to the
transducer by alternately driving one high and the other low. It's also
going to be much more accurate at frequency control than the 555.

If I connect the TX PIC serial output pin straight to the RX PIC
serial input pin then the receiving LED lights up during the program
cycle just fine. However if I connect the 555 output pin to the RX PIC
then it lights up only occasionally. A sync problem I'm guessing
caused by the 555 duty cycle? It was set to 55% and I changed it to
50% which made things worse. I'm unsure what to do here as I read that
the duty cycle for a transducer should be less than 60% for it to
operate properly and also that connecting a transducer straight to a
555 isn't a good idea. The 555 isn't stable at the resonant frequency
as a reverse voltage causes the frequency to jump about.

If a 1 bit is represented by ~10 cycles of sound and a 0 bit by silence
(or vice versa) you probably have issues with reflected signals
confusing the receiver. At 1200 baud a bit time is about 1mS. Your
sound signals only travel 1 foot during this time, and many reflections
are delayed by several mS. This could result in bits showing up
literally out of sequence to the receiver. You need to slow your baud
rate way down.

You also haven't mentioned any amplification stages on the receiver.
What are you using to condition the received signal before feeding it to
the PIC?

I've just seen a circuit where a modulated input goes to the Control
Voltage pin of a 555 (astable mode), the output having a pullup
resistor. Another circuit provides control over the duty cycle without

changing the output pulse frequency.
I can combine them and try it but is it the best way to go about this?
Is there a better way considering the limitations of my PIC?

Yes, I think there is a better and easier way.

Perhaps a tone controller or are they not fast enough?
PIC----567----INVERTER----TRANSDUCER

Your making it harder than it needs to be.

Maybe going up to 40kHz with a crystal locked TX inverter as in the
link below but how does one connect it to the PIC for serial AM? I
have a 40Khz crystal I pulled from some old junk which I could use and
the crystal eliminates tuning. I can't find any 24kHz crystals
locally.
http://info.hobbyengineering.com/specs/DIY-k49.pdf.
PIC----CRYSTAL LOCKED INVERTER----TRANSDUCER

Now you are aproaching Rube Goldberg status. ;-)

Any advice on how to go about making this work reliably welcome.

The more complicated you make it, the harder it will be to make it work
reliably. Especially without a scope. Do you have to use ultrasonics?
How about IR, it should give you as much range with less noise issues
and virtually no reflection issues. The receiving end is allot easier
as well since you can use a cheap off the shelf receiver to remove the
38Khz carrier and give you plain serial data.

You can use a TMR interrupt to generate the 38Khz carrier on the sending
side, or you could just bit bang it out using inline delay routines. To
make things simple you could have a TMR interrupt toggle an output pin
at 38Khz continuously. You then connect this pin to one input of an AND
gate. You connect another output pin to the remaining input of the AND
gate and use it to toggle the carrier on and off to send data.

I can help you with the code to get timer interrupts working if you
like.

 

[Ken Smith]

In article <pan.2005.01.29.18.43.20.815905@att.bizzzz>,
keith <krw@att.bizzzz> wrote:

(1)
I make a documentment called Physics.html

(2)
I save Physics.html to the CD.

(3)
Months pass and lots of things happen

I edit Physics.html to add the proof of the existance of God.
You write a new CD because you have created new data.

(4)
My computer gets infected

I find more proof and in my research I've found the secret of cold
fusion.
You write a new CD because you have created new data.
(5)
I clean off my system and re-install from safe media

(6)
I copy Physics.htlm from the CD

At this point my computer is not infected and I have Physics.html back.

...and lost the proof of God *and* the secrets of cold fusion. If you
saved the proof of God to CD *after* editing Physics.html, at least you
have that. If you saved after you added the secrets of cold fusion, that
copy is infected and your system is now reinfected.

HTML files can't carry viruses so I'm safe.

You say you installed Win98. On a clean partition? Is the MBR intact?

To re-install Win-ME you have to wipe out stuff so that Win-ME doesn't
think that this is merely a repair. If Win-ME thinks it is a repair it
carefully keeps all of the viruses safe.

If you wipe stuff, Win-ME upgrade disks refuse to install. They won't
even accept a Win-98 CD as proof of this being a real upgrade and not a
pirate.

I have to install the Win-98 to get the machine into a state that the
Win-ME will then over write. To make the Win-98 install, you can't have
the Win-ME installed.

I have to use my Win-98 CD, not hers. Hers is an upgrade version.

Once the system is brough back to a base install of Win-ME, I'd like to be
able to update it before hooking onto the net. Microsoft has now made
that imposible for me to do. I can't download the updates onto my Linux
box.

--
--
kensmith@rahul.net forging knowledge

 

[JeffM]

Let's see what happens when everybody's mother is running linux,
and the support for the 200 million users
is Linus Torvolds and 100 teenage undergrads.
Robert Monsen

Ah. This leads to one of my favorite topics:
Microsoft's business model (which is upside-down).[1]
You give them money up front for software
(and they tell you what you can't do with it)
then, when you have problems, often they are no help
(unless you are MegaCorp with megabux).

The new paradigm is: Get the software free
and pay e.g. GeekSquad when you have problems.

[1] At this point, it would be easy to get off on a tangent
about the RIAA's business model vs. that of The Grateful Dead.
Y'know: *Bring your recorder to the concert
--we make our $$ performing*.

 

[John Popelish]

royalmp2001 wrote:

I need to build a voltage divider for a 9v battery that will produce
0.25v on one leg and the rest on the other leg.

The 0.25V must not change even if battery voltage drops, so a pure
resistive divider is not suitable.... and I don't think there are 0.25V
Zeners available. Perhaps something with an ordinary diode will do the
trick but that is still 0.7V I think.

Any help??? It must be as simple and cheap as possible. Total load
current drawn from the configuration will be no more than 4mA.

My application is a CMOS 555 set up as an oscillator but I need the
square waveform to be offset from ground by 0.25V. So I guess some kind
of divider is necessary so that the chip runs on 8.75V supply from the
divider, leaving the ground rail 0.25V below this.
Thanks....hope this all makes sense

How accurate must the 0.25 volts be? Might a schottky diode
paralleled with a capacitor under the 555 do? A rail to rail opamp
and voltage reference chip could be combined to make a 0.25 volt
regulator with a few milliamps capability, but it is getting
complicated. Can you elaborate on why the output needs this offset?
There may be a better solution from that end.
--
John Popelish

 

This is not related to the dead battery but I live in Taiwan and we
have the phone things you're talking about. A little cell phone cradle
that lights up when your cell phone rings. Usually they are quite goofy
looking like a hand or something like that. If your interested I can
send you one.
Raul

 

[John Hines]

"Ringo Langly" <rlangly@gmail.com> wrote:

First... I want to run two phone lines on the Cat5 -- which will
eat-up two pairs and leaves me 2 more pairs. Is it possible to run
audio over those other two pairs?

Yep.

By audio, I mean wire-up a standard
Left and Right (RCA) jack to either pair for stereo audio. Is this
possible? I'll have a patch panel each cable will run to, so wiring-up
some audio cables shouldn't be too difficult. I'm just technically not
sure if audio will even run over a small gauge of wires for this length
-- which I'm looking at 50-60 feet. Also I'm not sure if there'll be
interference with two phone lines and two sets of audio cables running
through the same Cat5 cable -- given the cables can support the audio.

Possibly, but if your on the phone, you shouldn't be as worried about
the audio on the stereo.

 

[Mike Barnes]

In comp.home.automation, Ringo Langly wrote:

First... I want to run two phone lines on the Cat5 -- which will
eat-up two pairs and leaves me 2 more pairs. Is it possible to run
audio over those other two pairs? By audio, I mean wire-up a standard
Left and Right (RCA) jack to either pair for stereo audio. Is this
possible? I'll have a patch panel each cable will run to, so wiring-up
some audio cables shouldn't be too difficult. I'm just technically not
sure if audio will even run over a small gauge of wires for this length
-- which I'm looking at 50-60 feet.

What you want is entirely possible using a KAT5 transmitter and
receiver.

http://www.kat5.tv/index1.html

Although the KAT5 units are primarily for video, they convey an
audiophile-quality stereo signal. The wiring is as follows:

Blue (4&5) Left Audio
Orange (1&2) Composite Video/S-video Luma
Green (3&6) Right Audio
Brown (7&8) 2nd Video Circuit/S-video Chroma/Digital Audio

You can connect the audio pairs and leave the others unconnected. That's
what I do, and it works perfectly. Alternatively you could use SPDIF and
get *two* stereo signals down your two pairs.

Also I'm not sure if there'll be
interference with two phone lines and two sets of audio cables running
through the same Cat5 cable -- given the cables can support the audio.

I can't tell you about phone lines, but FWIW I have about 10 metres of
cat5 fixed wiring conveying KAT5 audio and ethernet in the same cable.
[To the structured wiring police: yes, I know, I know.] At each end
there's a specially-wired dual-RJ45 wallplate, with one outlet labelled
"LAN" and one labelled "Audio" going to the KAT5 unit. I've detected no
interference. To ask about phone lines you could contact Keith Doxey,
the KAT5 designer:

http://www.kat5.tv/contact.html

--
Mike Barnes

 

[Tomi Holger Engdahl]

"Ringo Langly" <rlangly@gmail.com> writes:

Hi all,

I'm looking at wiring up my home with Cat5, and I have some rather odd
questions. First every room will be wired with two pairs of Cat5 cable
-- one definately for ethernet but the other I'd like to keep open for
other applications, which is the purpose of this email.

First... I want to run two phone lines on the Cat5 -- which will
eat-up two pairs and leaves me 2 more pairs. Is it possible to run
audio over those other two pairs? By audio, I mean wire-up a standard
Left and Right (RCA) jack to either pair for stereo audio. Is this
possible?

It is possible to run normal line level audio signals through
CAT5 wiring together with other signals. I have personally
done this, typically with video signal on the same cable.
But there shoudl not be any problem with telephone on the same
wire either (some crosstalk from rign signal and pulse dial possible).

There is on "secret" on running the audio signal through CAT5 wiring
successfully: the signals must be balanced.
Balanced signals can be transported nicely through twisted pair
cables without considerable crosstalk or without picking much
noise on the way. The CAT5 twistred pair cable is not a suitable
medium for transporting unbalalanced audio signals (the
signal transfer method used n consumer audio RCA connectors and such).
If you wire unbalanced signal source to CAT5 UTP, you will
get considerable crosstalk between the signals on different pairs
and the signal will very easily pick up humming noise.

Balanced signals are available directly from professional audio
equipment and can be directly wired to CAT5 UTP. One audio
signal takes one wire pair. For left and right audio you need two
wire pairs.
If you want to connect equipment that do not have balanced
connections on them, you need to use audio transformers on the
both ends of the CAT5 UTP cable to perform balanced-unbalanced
conversion (from unbalanced RCA to balanced on signal source end and and
back from balanaced to unbalanced in the receiving end).
In addition to signal balancing such tranformers will provide
galvanic isolation on the audio interconenction
(without isolation many times conenctions from one room
to another will pick up humming noise).
Ground currents can't flow across the insulation between
the transformer windings.
Audio transformers are available as separate components
and there are also commecially adapters that can convert
RCA audio to CAT5 wiring and back.

I'll have a patch panel each cable will run to, so wiring-up
some audio cables shouldn't be too difficult.

You need to wire those audio transforemers to your circuit as well
between your RCA and wire on the wall. You just can't just patch-in
the cable from the hifi equipment to your patch panel.

I'm just technically not
sure if audio will even run over a small gauge of wires for this length
-- which I'm looking at 50-60 feet.

Line level audio will run though this wire this distance quite well.
Been there, done that. I have one system at my home where I run
the audio and video trough CAT5e wiring from my computer room
to my living room TV/hifi system. Cabling distance is about 15 meters.
No problems. The adapters are homebuilt (my own design).
The audio adapter part is built out of one of those RCA stereo audio
signal isolators sold or solving ground loop problems.
Basicly have opened one the device (it includes two audio transformr),
cut out the original signal out cable, disconnected the audio
transformer secondaries from original wiring completely and
soldered to two pairs on the CAT5 wiring. Works very well,
is easy to build (if you know how to solder), and cost
is very reasonable (those RCA isolators cost around 10-20 USD).
Just build two of theose adapters, one for each end of the connection.
Or go to a shot and buy a ready made box at considerably higher price.

Also I'm not sure if there'll be
interference with two phone lines and two sets of audio cables running
through the same Cat5 cable -- given the cables can support the audio.

There is potential for some interference, but it could work
well acceptably for you.

Thanks in advance for any ideas or suggestions. I'm just trying to
make wiring my home both easier and as simple as possible. Take care,
Ringo

--
Tomi Engdahl (http://www.iki.fi/then/)
Take a look at my electronics web links and documents at
http://www.epanorama.net/

 

[Mark Fergerson]

Blackbeard wrote:

We built our caps using the salt water/beer bottle trick. When we
fired it up, the bottles started to glow purple.

That's not a good sign. Is the glass itself glowing, or the air
around them? If the latter, that's just corona (air excited into glowing
visibly, the electrical equivalent of pressure-caused leakage). If the
former, you may be producing x-rays.

We never got any streamers. At the toroid, we noticed some slight
sparking between the magnet wire and the connection to to toroid. Out
of curiosity, we place a florescent bulb on top of the toroid. The
bulb glowed on our test....but still no streamers. Since the bulb
glowed, I assume it was getting power to the toroid. But we let the
thing run for at least 30 seconds and never saw lightening.

Good powers of observation! Sparks where the secondary connects to
the toroid indicates a poor electrical connection. Is it soldered,
bolted, duct-taped, what? Did you remember to strip the insulation off
before making that connection? I ask because we've all made these mistakes.

The bulb lighting does indeed indicate several things; first, you're
getting some power transfer from primary to secondary, thence to the
bulb, so the thing is _trying_ to work.

As for not getting lightning, likely it isn't tuned properly, among
other things. BTW, try running it in poor lighting (make damn sure you
know where everything is, including the main cutoff switch FIRST).
That'll allow you to look the entire setup over for corona. Corona
anywhere but the toroid is a Bad Thing.

Side note; remember that the toroid is one plate of a capacitor whose
value depends partly on its surface area. Once you do get the thing
tuned, putting a fluorescent or anything else on or near the toroid will
detune it somewhat from resonating with the primary.

So we're stymied. Don't have a clue why we have no streamers. We had
approx. 2mm on our spark gap.

Might be too large a gap. Can you tighten it up a bit?

Here's how it's built...

Primary coil - 15 turns using 1/4OD Copper tubing
Secondary - 1500 turns using 24-gauge wire
Magnet wire from secondary connect to toroid at the top
Magnet wire from bottom of secondary goes to ground

Capacitors = 6 bottle filled with salt water, wrapped with aluminum
foil all daisy-chained together with wire.
One single wire on the daisy chain connects to the transformer
The second wire on the transformer connects to an aluminum pan that
makes a connection with those bottles where the aluminum makes contact
with the aluminum pan.

Fine so far.

Spark Gap - the spark gap doesn't make a whole lot of sense to me. We
pulled a second wire off the two posts from the transformer and the
spark gap was not connected in-line with anything. This is how our
plans show this is supposed to be done.

Your post announcing the schematic showed up in the binaries group,
but not the schematic itself. Does your ISP not allow you to send
binaries? I'd _really_ like to see it.

It sparked at the spark gap

Good sign

Bottle glowed purple

bad sign

florescent light lit up

good sign

...No streamers.

I warned you not to be surprised. Tesla coilers proudly (as you're
learning, for good reason) proclaim "first light" when that happens.

We have to be close. Doesn't that florescent light glowing suggest I'm
getting power up there?

Yep, just not enough.

the toroid is made from a piece of semi-rigid aluminum duct attached
to a 5-gallon paint buck lid to hold it's shape. We connected the
toroid using an a plastic toilet flange connected to that 5-gallon
bucket lid. The tolet flange fits right onto the 4" PVC pipe we used
for the secondary coil.

Sounds sturdy, which is a good thing.

Any help or suggestions would be appreciated.

Show us the schematic!

Mark L. Fergerson

 

[Trudeau]

"John Fields" <jfields@austininstruments.com> wrote in message
news:ebf701pboiq0451nka6f09vn72vdrhqmga@4ax.com...

On Fri, 4 Feb 2005 12:23:58 -0600, "Trudeau" <Trudeau@123.com> wrote:


"John Fields" <jfields@austininstruments.com> wrote in message
news:i25701t8rfm5qn4sonfnioeav1h2ditn45@4ax.com...
On Fri, 4 Feb 2005 09:25:45 -0600, "Trudeau" <Trudeau@123.com> wrote:


Thnaks again for your suggestions.
Could someone explain, ( Simple as you can ) what the advantage of an
isolation transformer would be in this project. As I understand it
basically
you have a transformer that separates the 120 house into I suppose 120
coming from the other half of the transformer. (Is this called a 1 to
1).
Im
not sure what the difference is. Unless as I come to think of it you
are
reducing the amps from 15 house to say 1 or 2. I suppose this would
have
some added safety.
Please Carify.

---
The reason for the isolation transformer is to place a galvanic
barrier between whatever's plugged into the output of the transformer
and the mains. That way, the likelihood that you'll kill yourself or
the equipment you're working on/with will be made somewhat smaller.

--
John Fields

Thanks for that.

I'm a little unclear on what the Galvanic barrier does.

I ve done a little research and learned that a galvanic process is a
process that creates electricity. eg electricity in frogs legs.
Secondly I have always know that when you put certain metals together
that
you get corrosion. I have now learned the name for this is a Galvanic
Process.
As far as the discussion at hand I have found that a Galvanic Barrier in
a
transformer :

A. Galvanic barrier has no metal metal contact, Well Yes of course its a
transformer. It uses fields to pass the current and air as the barrier.

---
Well, only partly. The insulation on the magnet wire and the nylon
walls of the bobbin separating the primary and secondary (if the
transformer is wound that way) do the galvanic isolation.
---

I guess that not being directly connected to the mains is good. But its
still
120volts.
B. A Galvanic barrier cuts down on noise. Not sure its important in this
case.
C. That a G.B. prevents ground loops. This I can see as being important.

Am I right here. Are there more reasons to use the isolation transformer?
I guess my confusion is that if the voltage coming into the transformer
is
the same coming out accept for the fact that it is cleaner and perhaps
exactly 120 Volts. Im not sure what more added safety it adds, accept for
the things I noted above. Sorry to be dense. What am I missing?

---
If you're working with mains hot and neutral directly, without going
through a transformer and you get hot and neutral reversed, the
chassis of what you're working on could be connected to mains hot with
the embarrassing result that you could fry a scope probe as soon as
you clip the probe's ground to chassis or to whatever you thought was
ground in the circuit. Worse, you could be holding on to the chassis
when you grab the alligator clip... Interpose an isolation
transformer between the DUT (device under test) and the mains and
those problems go away. Of course you'll still have 120V coming out
of the transformer, but if you don't know enough not to grab ahold of
that, you'll probably be a candidate for a Darwin award soon,
anyway!^)

--
John Fields

Thanks for your patience and helping me to understand.

Regards

 

[Laurence Payne]

On Thu, 03 Feb 2005 18:44:45 -0600, John Hines <jbhines@newsguy.com>
wrote:

By audio, I mean wire-up a standard
Left and Right (RCA) jack to either pair for stereo audio. Is this
possible? I'll have a patch panel each cable will run to, so wiring-up
some audio cables shouldn't be too difficult. I'm just technically not
sure if audio will even run over a small gauge of wires for this length
-- which I'm looking at 50-60 feet. Also I'm not sure if there'll be
interference with two phone lines and two sets of audio cables running
through the same Cat5 cable -- given the cables can support the audio.

Possibly, but if your on the phone, you shouldn't be as worried about
the audio on the stereo.

I expect the 'phone circuits, now or in the near future, may be
carrying an ADSL carrier for broadband internet.

 

[Ban]

If I had money, I would have left this planet a long, long time ago
and be in a galaxy far far away.

You are already.
--
ciao Ban
Bordighera, Italy

 

[Robert Monsen]

phaeton wrote:

I'll have to take a look at the library (haven't made it that far yet)
for these, just to see. I had once borrowed from the Library a book
called "Basic Electronics" (this is going back maybe 10 years ago in a
different state) but that's such a generic title it could be different
than Grob. I don't remember the author, and the book was circa 1983
iirc. Might have been an older version of it.

Thanks!

There have been a few versions of "Basic Electronics" by Grob. The one I
have is the 8th version. The copyrights go back to 1959...

One of the authors of AoE frequents the sci.electronics.design group,
and has made some mention that he is working on a 3rd edition. No word
on when it'll be out, but the last one was 1989, so they are clearly
taking their time. If you are going to buy, you can get technical books
much cheaper at www.bookpool.com.

Good luck. Also, if you are in California, try the community college
system. It's got some great introductory classes, and isn't that
expensive. Lots of people take night classes.

--
Regards,
Robert Monsen

"Your Highness, I have no need of this hypothesis."
- Pierre Laplace (1749-1827), to Napoleon,
on why his works on celestial mechanics make no mention of God.

 

[Robert Monsen]

Robert Monsen wrote:

increase the impedance of the output. If your comparator is open
--------

decrease


--
Regards,
Robert Monsen

"Your Highness, I have no need of this hypothesis."
- Pierre Laplace (1749-1827), to Napoleon,
on why his works on celestial mechanics make no mention of God.