Chip with simple program for Toy

[DecaturTxCowboy]

pbdelete@spamnuke.ludd.luthdelete.se.invalid wrote:

DecaturTxCowboy <forgetit@bummer.com> wrote:
pbdelete@spamnuke.ludd.luthdelete.se.invalid wrote:
I figured that out, but the science is in the details =)
I brainstorming on a solution to speed up the process.

What part of what process?

I want a "print pcb" machine

Ummm..let me rephrase that. Are you looking to do one-time PCBs or a
batch of just a few, or a production line for PCBs?

The reason I ask it there are so many ways to go about making PCBs and
the best way is determined by your volume.

 

[Brian]

"Ryan" <quakeserver149@yahoo.com> wrote in message
news:8p3Uf.633827$084.574836@attbi_s22...

I'm trying to learn about pressure transducers and I've learned a tiny bit
on the web, but not found it as fruitful as I had hoped. (Or I just don't
understand what to look for.)

Do they permit air to pass through them, or only into them, like a
pressure tank?

Is their output linear with pressure throughout its rated range? If the
transducer is good from 0-30 psi, then does the output range from
something like 0 to 30 volts? When their max rated pressure is reached
and then exceeded, does the output stop changing? Is it accurate to say
the transducer is saturated?

Would the power supply in this example need to be 30 volts? Does the
supply need to be steady? If the supply fluctuates, does that throw off
the measurement? If the supply is noisy DC, does this throw off the
measurement?

It seems like they are always zero to X psi rating. Can the same
transducer measure vaccuum too? If I want to guage -20 psi up to 40 psi,
can this be done with a single transducer? If not, is there a such thing
as using two transducers to measure this range and to install one of them
backwards?

Thank you.

Have a look at
http://users.pandora.be/educypedia/electronics/sensorspres.htm
Brian

 

What part of what process?

I want a "print pcb" machine

Ummm..let me rephrase that. Are you looking to do one-time PCBs or a
batch of just a few, or a production line for PCBs?

The reason I ask it there are so many ways to go about making PCBs and
the best way is determined by your volume.

For development purposes (one-off). For massproduction there are other means.

I want this process in one go:
Source file -> Mask -> Exposure

 

[Michael A. Terrell]

Abstract Dissonance wrote:

hmm, wasn't his first post sorta an attack too?

"There is no electronics question in your post!"

It looks like a simple statement that you don't seem to agree with.

This maybe or may not be true but surely the parallel port is used
indirectly with electronics? I am asking this question simply because I
want to use some electronic devices and monitor there digital outputs... so
indirectly it has everythign to do with electronics... and surely many
people here in "sci.electronics.xxx" has messed with the parallel port in
some fashion or another and probably has had the need to monitor/log the
port?

If the port is defective, or you are designing the port, it is
electronics. The rest is software related.

The fact is this is probably the best place to ask this question since it is
directly used for an electronics application... I could be wrong but he
obviously thought that my OP didn't belong in here and he had to point it
out.

He could have said something like

"You might find better luck asking in blah.blah".

Cause basicaly he's implying that I'm asking something that is completely
off base in this group, which I think it isn't.

You seem to have a chip on your shoulder, and a bad attitude will get
you very little help. Its your choice.

And I seriously doubt I would get any answeres in alt.comp.freeware that I
couldn't get googling.

Then why are you here instead of "Googling"?


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

 

[DecaturTxCowboy]

pbdelete@spamnuke.ludd.luthdelete.se.invalid wrote:

For development purposes (one-off). For massproduction there are other means.

I want this process in one go:
Source file -> Mask -> Exposure

http://www.fullnet.com/u/tomg/gooteepc.htm

 

[Chris]

Jason S wrote:

"Jason S" <jst3712@iprimus.com.au> wrote in message
news:44221bd1$1_1@news.iprimus.com.au...
Hi,

Bit of a dumb question here.....

Not having much luck with circuits triggering SCR's.
What I want to do is trigger an SCR, and I know they require a short burst
of current. Triggering them manually with a wire works fine.

Trouble is, how do I get another circuit to trigger it momentarily?
e.g. Let's just say I have a 555 timer IC (another circuit), and I want
its 555 output pin to trigger the SCR, even if the 555 timer output
changes back to 'low' again. The SCR must remain on until power is turned
off to the actual SCR, even if later the 555 was switched off completely.
This is just an example.

I thought a non-elec cap and a high value resistor would work (providing a
pulse), but it didn't affect the SCR at all.. not sure if its due to the
type of SCR I'm using or not. If I manually trigger the SCR with a lead,
it works fine, so its not a connection problem.
The SCR I'm using is a C106Y and have also tried a BT169D (from Jaycar)..

This is what I tried, assuming would work:



PWR----||----+-----> To SCR gate

10n | (pulse)

|

_

| |

| | 10M

-

|

|

GND



I know about the electromagnetic induction method, and that a 555 can be
configured to work like an SCR, but isn't there a much quicker better way,
similar to the above?



Thanks in advance.




I think it's working now. I hooked up a transistor between the cap/res and
SCR to amplify the short 'burst'. It seems like the burst may have been
extremely weak to trigger the SCR directly previously.
+V
|

|

____ |/

PWR----||----+-----|____|--K NPN
10n | 2K2 |\
| |
_ ------> SCR Gate
| |
| | 10M
-
|
|
GND



Any suggestions or comments regarding this are very welcome, as I'm still
learning! =)



Jason.

Hi, Jason. A couple of things:

* SCRs have a spec called I(gt), the minimum gate current guaranteed
to turn on the SCR. The typical I(gt) for the C106Y is 50mA, and can
be up to 200mA. A 555 just can't source that much current.

* Your transistor booster circuit will work much better for the C106Y.
You're depending on the current gain of the transistor, though, to
limit the current going into the gate of the SCR. Not only that, but
you haven't taken the leakage current of the transistor into account --
for your other SCR, it could cause false triggering (although that's
not much of a problem with the C106 line). You might want to add a
couple of resistors like this (view in fixed font):

|
| VCC VCC VCC VCC
| + + + +
| | | | |
| .--o---o--. | |
| | | | .-.
| | | | ( X )
| | |.01uF | '-'
| | | 3|| ___ |/ |
| | o--||-|___|-o-| |
| | 555 | || R1 | |> V
| | | .-. | ___ -
| | | R2| | '---|___|-o/|
| | | | | R3 | |
| | | '-' .-.|
| | | | R4| ||
| | | | | ||
| '--o------' === '-'|
| | GND | |
| === o-'
| GND |
| ===
| GND
|
(created by AACircuit v1.28.6 beta 04/19/05 www.tech-chat.de)

If you've got a 12V supply voltage, try 1K for R1, 33K for R2, 33 ohms
1/2w for R3, and 220 ohms for R4.

Also, there are SCRs which are made to be triggered on low gate
current. They're called logic level or sensitive gate SCRs. Your
BT169D is one of those. The NTE equivalent data sheet says gate
trigger current can be less than 1mA. You should be able to drive it
from the 555 directly without the transistor, but you may want to bump
up the cap to 0.1uF or 0.22uF. This gives more time for the SCR to
turn on. It might not be wise to use the transistor follower to crank
so much currrent into this SCR -- you are getting close to the peak
gate current rating.

I hope this has been of help.

Good luck
Chris

 

[Bob Masta]

On Wed, 22 Mar 2006 07:48:05 -0600, "Abstract Dissonance"
<Abstract.Dissonance@hotmail.com> wrote:

I'm just doing this for the keyboard so I just need it to run from 10khz to
20khz. Its not clocked but if the application could use one port for the
clock to sample another port then it should work? Or even just set the
speed at which to sample?

Basicaly what I want to do is hook the keyboard up to the parallel port and
then hit keys and read the data being sent. I have the parallel port all
setup to do this easy but it looks like I'm going to have to do it with a
serial port since that seems to be the only one with the extensive
applications.

Yeah, the parallel port would be a bad idea for this anyway, since
you would have to poll it at a high rate to be sure of not missing
key scan codes. Note that the scan codes are not just a single
byte per key press... there can be a whole stream of bytes from
hitting a single key. If you want to have a look at what is going on,
I have a little free utility you can download from
www.daqarta.com/download.htm
called KEYCODE.EXE. (It's down near the bottom of the
page under "Utilities".) HOWEVER, this is only for use under
real-mode DOS, which you can't get under WinXP, 2k, or NT.
From Win9x you have to use Start- Shutdown - Restart in MS-DOS Mode.
This will write all the scan codes to the screen as they happen,
which can be rather eye-opening.

There might be a way to use the parallel port under DOS if
you can rig up the keyboard to generate an interrupt. The port
does support interrupts, and that would save you having to poll
for bytes.

Best regards,


Bob Masta
dqatechATdaqartaDOTcom

D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Home of DaqGen, the FREEWARE signal generator

 

DecaturTxCowboy <forgetit@bummer.com> wrote:

pbdelete@spamnuke.ludd.luthdelete.se.invalid wrote:
For development purposes (one-off). For massproduction there are other means.

I want this process in one go:
Source file -> Mask -> Exposure

http://www.fullnet.com/u/tomg/gooteepc.htm

If I understand it right:

* Print pattern/mask on a special (glossy) kind of papper.
* Ironing it onto a copper pcb at approx ~205 Celsius, 111-134 Newton.
* Soak the papper, and rub "it" off.
* Put the pcb in the etch bath.

The instructions is a bit unstructured

The procedure still seems a bit messy. I have some other ideas that might push
the time significantlty down.

How is the copper film attached to the pcb .. ?

 

[DJ Delorie]

pbdelete@spamnuke.ludd.luthdelete.se.invalid writes:

If I understand it right:

Yup. Google for "toner transfer PCB". They even sell special paper
for it.

 

DJ Delorie <dj@delorie.com> wrote:

pbdelete@spamnuke.ludd.luthdelete.se.invalid writes:
If I understand it right:

Yup. Google for "toner transfer PCB". They even sell special paper
for it.

Found this excellent guide: http://pminmo.com/pcbmaking.pdf

The key is that toner ink will protect the copper from etch fluid?

 

pbdelete@spamnuke.ludd.luthdelete.se.invalid wrote:

DecaturTxCowboy <forgetit@bummer.com> wrote:
pbdelete@spamnuke.ludd.luthdelete.se.invalid wrote:
I figured that out, but the science is in the details =)
I brainstorming on a solution to speed up the process.

What part of what process?

I want a "print pcb" machine

You might want to check out the Homebrew_PCBs discussion group, at
http://www.yahoogroups.com .

[Or, if you can spend some $, there are CNC (router) machines made
specifically to produce prototype pcbs automatically.]

Good luck.

Tom

 

pbdelete@spamnuke.ludd.luthdelete.se.invalid wrote:

DJ Delorie <dj@delorie.com> wrote:

pbdelete@spamnuke.ludd.luthdelete.se.invalid writes:
If I understand it right:

Yup. Google for "toner transfer PCB". They even sell special paper
for it.

Found this excellent guide: http://pminmo.com/pcbmaking.pdf

The key is that toner ink will protect the copper from etch fluid?

Laser printer and copier "Toner" (not ink) is mostly plastic, which the
acids usually used for etching-away the unwanted portions of the copper
can't eat through.

 

[ehsjr]

pbdelete@spamnuke.ludd.luthdelete.se.invalid wrote:

DJ Delorie <dj@delorie.com> wrote:


pbdelete@spamnuke.ludd.luthdelete.se.invalid writes:

If I understand it right:


Yup. Google for "toner transfer PCB". They even sell special paper
for it.


Found this excellent guide: http://pminmo.com/pcbmaking.pdf

The key is that toner ink will protect the copper from etch fluid?

Yes. And if you take the time to absorb and understand the
information in the link that Decatur posted, it is even better
than the good one you posted.

Let me emphasise some key points in the process:
1) You want the copper on the PC board you will use
to be *clean*. I mean *CLEAN*
2) Do *not* rush the ironing. Use the 4 or 5 minutes
recommended and keep steady firm pressure while moving
the iron to prevent scorching.
3) Soak the bejusus out of the paper and board after
ironing - dunk it in a container of hot water and let
the thing soak until the paper comes away from the copper
without pulling the toner with it. In other words:
"DON'T PULL ON THE DAMN PAPER TOO SOON". Ask me how I know.
4) Gently rub the board to get most of the residue paper
off. Residue that seems to be embedded in the toner won't
hurt as long as the toner paths have crisp edges.

5) This is not so key - but bears mentioning. Etching
takes time. It can be sped up by keeping the etching
solution warm and by agitating it. But don't look to set
speed records. I use a container that I can tilt to
expose the board to see how much copper has been removed
so that I don't have to stick anything in to the solution
to grab the board to inspect it. That keeps the etching
solution in the container, rather than getting on a glove
or a tool. Once it is out of the container and onto a tool
or a glove, it is one short step from staining something.
And it *will* stain.

When etching is done, wash the board well with water to remove
any etching material. Then remove the toner, drill the holes,
and build away.

Ed

 

[DJ Delorie]

ehsjr <ehsjr@bellatlantic.net> writes:

I use a container that I can tilt to expose the board to see how
much copper has been removed so that I don't have to stick anything
in to the solution to grab the board to inspect it.

Last time I etched a board, I attached something to the board that
stuck up above the etchant. Thus, I had a handle that I couldn't
accidentally put down somewhere. It was a tiny board, I think I just
soldered a wire to an empty corner, but I suppose supergluing some
toothpicks along the edges would work too.

 

[DecaturTxCowboy]

pbdelete@spamnuke.ludd.luthdelete.se.invalid wrote:

How is the copper film attached to the pcb .. ?

Hold on here. Are you asking how the copper is actually attached to the
phenolic or fiberglass base??? If you indeed are, I think you might be
way over your head in working the printed circuit boards at this point.

 

[John Fields]

On 23 Mar 2006 18:55:28 GMT,
pbdelete@spamnuke.ludd.luthdelete.se.invalid wrote:

How is the copper film attached to the pcb .. ?

---
To the substrate?

With glue.

--
John Fields
Professional Circuit Designer

 

Thanks a lot. So far that is working perfectly. I will post a link to
my project once I have the site up, for anyone who is interested.

 

[Monica]

Monica wrote:

do any one know how to calculate the isolation and insertion loss of a
single-pole, single throw switch constructed by two identical PIN diodes?
Thank you


------------------------------------------------------------------------

The input and output load is Zo (50ohm) and
assuming it is a series resistor (R)in forward biased.
and a series Cap (C) in reversed biased.

 

[nyffeler]

In article <44204bd8$0$486$cc7c7865@news.luth.se>, pbdelete@spamnuke.ludd.luthdelete.se.invalid wrote:

I just had a thought.. if pcb's are made by exposeing them to UV light.
Followed etch bath. Could sunlight later on compromise the pcb .. ?

Do you mean the glasfibers epoxy substrate?

Most epoxy resins are not resistive against high UV radiation. But I can't
say anything about the epoxy used in FG4 PCB's.
I expect a soldermask will give a additional UV protection.

 

[DecaturTxCowboy]

nyffeler wrote:

Most epoxy resins are not resistive against high UV radiation. But I can't
say anything about the epoxy used in FG4 PCB's.

Eventually the epoxy breaks down in sunlight, unless is has a
sacrificial UV inhibitor like the grey PVC for outside use has or blue
dye like Phelps Dodge fiberglass base station antennas which are more
resistant to sunlight than the painted Decibel Products antennas.

I expect a soldermask will give a additional UV protection.

I think sunlight would be the least of the problems if an exposed PCB
was used outside with no cover or box whatsoever. Even if used inside a
UV radiating device, you could put the PCB in a box to shield it.