To Jim Weir

Jim,

From info I have located on the internet, I have cobbled together a
circuit diagram for illuminating my instrument panel using LED's. I was
wondering if I emailed you a copy, would you would be kind enough to
take a peek at the circuit and see if I missed anything? Electronics
isn't my expertise but I enjoy it all the same.

Thanks in advance,
Charlie Smith

Charlie Smith wrote:
Jim,

From info I have located on the internet, I have cobbled together a
circuit diagram for illuminating my instrument panel using LED's. I was
wondering if I emailed you a copy, would you would be kind enough to
take a peek at the circuit and see if I missed anything? Electronics
isn't my expertise but I enjoy it all the same.

Thanks in advance,
Charlie Smith

Hi Charles, can I ask you what you do for a living?

I'm sure there's something I could use your expertise for.

If you were a physician, you might be able to tell me if
the lemon juice I'm taking for gall-stones will help.
If you're a plumber, I am sure you could tell me about
the slope I need when laying new sewer lines.

Stuff like that.

I wouldn't ask, But I am pretty sure you are a nice guy.

Regards

Brian W

brian whatcott wrote:
Charlie Smith wrote:
Jim,

From info I have located on the internet, I have cobbled together a
circuit diagram for illuminating my instrument panel using LED's. I
was wondering if I emailed you a copy, would you would be kind enough
to take a peek at the circuit and see if I missed anything?
Electronics isn't my expertise but I enjoy it all the same.

Thanks in advance,
Charlie Smith

Hi Charles, can I ask you what you do for a living?

I'm sure there's something I could use your expertise for.

If you were a physician, you might be able to tell me if
the lemon juice I'm taking for gall-stones will help.
If you're a plumber, I am sure you could tell me about
the slope I need when laying new sewer lines.

Stuff like that.

I wouldn't ask, But I am pretty sure you are a nice guy.

Brian -

If you're implying Charlie is being presumptuous to ask for help, then I
believe you're out of line with your followup. Not only did he first
politely ask permission, the following author info is posted for Jim Weir
on page 71 of the February 2010 issue of Kitplanes magazine:

"Jim Weir began acquiring Aero'Lectrics expertise in 1959, fixing Narco
Superhomers in exchange for flight hours. A commercial pilot, CFI, and
A&P/IA, Jim has owned and restored four single-engine Cessnas. These
days, he runs RST Engineering and teaches electronics at Sierra College.
Ask him questions at rec.aviation.homebuilt or visit his site at
www.rst-engr.com/kiplanes."

Since there is an open invitation in black on white to ask him questions
on this newsgroup, there doesn't seem to be any merit to your
implication.

NOTE to Charlie: You should also consider directing your question to
sci.electronics.design. I used to read that group a few years ago and at
least back then it was a great resource. Had a few personal exchanges
with one of the authors of the text "Art of Electronics" (which was
required for my experimental physics class about a zillion years ago) who
hung out there; very nice group - and helpful if questions honestly
posed. Hopefully it still is.

Jim Logajan wrote:
brian whatcott wrote:
Charlie Smith wrote:
Jim,

From info I have located on the internet, I have cobbled together a
circuit diagram for illuminating my instrument panel using LED's. I
was wondering if I emailed you a copy, would you would be kind enough
to take a peek at the circuit and see if I missed anything?
Electronics isn't my expertise but I enjoy it all the same.

Thanks in advance,
Charlie Smith
Hi Charles, can I ask you what you do for a living?

I'm sure there's something I could use your expertise for.

If you were a physician, you might be able to tell me if
the lemon juice I'm taking for gall-stones will help.
If you're a plumber, I am sure you could tell me about
the slope I need when laying new sewer lines.

Stuff like that.

I wouldn't ask, But I am pretty sure you are a nice guy.

Brian -

If you're implying Charlie is being presumptuous to ask for help, then I
believe you're out of line with your followup. Not only did he first
politely ask permission, the following author info is posted for Jim Weir
on page 71 of the February 2010 issue of Kitplanes magazine:

"Jim Weir began acquiring Aero'Lectrics expertise in 1959, fixing Narco
Superhomers in exchange for flight hours. A commercial pilot, CFI, and
A&P/IA, Jim has owned and restored four single-engine Cessnas. These
days, he runs RST Engineering and teaches electronics at Sierra College.
Ask him questions at rec.aviation.homebuilt or visit his site at
www.rst-engr.com/kiplanes."

Since there is an open invitation in black on white to ask him questions
on this newsgroup, there doesn't seem to be any merit to your
implication.

NOTE to Charlie: You should also consider directing your question to
sci.electronics.design. I used to read that group a few years ago and at
least back then it was a great resource. Had a few personal exchanges
with one of the authors of the text "Art of Electronics" (which was
required for my experimental physics class about a zillion years ago) who
hung out there; very nice group - and helpful if questions honestly
posed. Hopefully it still is.

Thanks Jim. Your reasoning is quite correct and thanks for the
suggetion. As Jim's articles are the primary reason I have a Kitplane's
subscription and as I have purchased items from RST in the past, I
thought I might ask here. But to be honest, I did have reservations as
one never knows if it would do any good. Jim may get many such requests
and simply cannot answer them. Even though others may be qualified to
answer, there is always the possibility one might encounter the kind of
person you would expect to find living in those sloping sewer lines and
that made me really hesitant. As a rule, I don't find these forums worth
the hassle. Perhaps is would be a more interesting electronics question
to find out how they get internet service down there.

Best regards.

Jim Logajan wrote:

From info I have located on the internet, I have cobbled together a
circuit diagram for illuminating my instrument panel using LED's. I
was wondering if I emailed you a copy, would you would be kind enough
to take a peek at the circuit and see if I missed anything?
Electronics isn't my expertise but I enjoy it all the same.

Thanks in advance,
Charlie Smith

Hi Charles, can I ask you what you do for a living?

I'm sure there's something I could use your expertise for.

If you were a physician, you might be able to tell me if
the lemon juice I'm taking for gall-stones will help.
If you're a plumber, I am sure you could tell me about
the slope I need when laying new sewer lines.

Stuff like that.

I wouldn't ask, But I am pretty sure you are a nice guy.

Brian -

If you're implying Charlie is being presumptuous to ask for help, then I
believe you're out of line with your followup. Not only did he first
politely ask permission, the following author info is posted for Jim Weir
on page 71 of the February 2010 issue of Kitplanes magazine:

"Jim Weir began acquiring Aero'Lectrics expertise in 1959, fixing Narco
Superhomers in exchange for flight hours. A commercial pilot, CFI, and
A&P/IA, Jim has owned and restored four single-engine Cessnas. These
days, he runs RST Engineering and teaches electronics at Sierra College.
Ask him questions at rec.aviation.homebuilt or visit his site at
www.rst-engr.com/kiplanes."

Since there is an open invitation in black on white to ask him questions
on this newsgroup, there doesn't seem to be any merit to your
implication.

NOTE to Charlie: You should also consider directing your question to
sci.electronics.design. I used to read that group a few years ago and at
least back then it was a great resource. Had a few personal exchanges
with one of the authors of the text "Art of Electronics" (which was
required for my experimental physics class about a zillion years ago) who
hung out there; very nice group - and helpful if questions honestly
posed. Hopefully it still is.

First rule of etiquette on newsgroups: to make a request for help in a
way so that any person who feels he can offer help, is able to do so.
If only one person's reply is to be valued, then it it OBVIOUS that the
email should go to the addressee only. I say it *is* obvious, but it
obviously isn't: still, it SHOULD be obvious, even to folks who have
taken undergraduate physics.

When Jim offers help via a newsgroup, I imagine he does not expect to be
the only responder in general. He would (I can suppose) be happier
offering corrections and enhancement on a selection of replies.
That is how everyone wins.

As it happens, in the long past, I have received kind treatment from
Jim Weir, so that I was able present his materials for setting up copper
tape antennas with ferrite stoppers in glass and fabric homebuilts to a
builder group. I am not amused when I see people sniping at him on
newsgroups, or appearing to take advantage of his goodwill. He has to
make a living, as do we all.

Moreover, since you mention it, I was able to swap Winfield an old
technical book that interested him for an autographed copy of that
splendid electronics reference in 1168 pages, The Art of Electronics, by
Paul Horowitz and Winfield Hill. At that time, the first edition was
still current.
I am pleased to see that Winfield, as generous with his advice as
Jim Weir, who was kind enough to autograph a first Edition for me, now
offers a third edition, no less helpful.


Brian Whatcott.

On Thu, 07 Jan 2010 15:39:13 -0500, Charlie Smith
wrote:

Jim,

From info I have located on the internet, I have cobbled together a
circuit diagram for illuminating my instrument panel using LED's. I was
wondering if I emailed you a copy, would you would be kind enough to
take a peek at the circuit and see if I missed anything? Electronics
isn't my expertise but I enjoy it all the same.

Thanks in advance,
Charlie Smith

charlie, assuming that you are using a 12 volt bus, all you need to do
to use an LED is put a 680ohm resistor in series with it.
so if you had an instrument that was lit by a small tungsten globe, in
theory, all you need to do is take out the lamp holder and wire in the
led and the resistor in its place. the led should then work with the
original switching.
you need to have a resistor in series with each LED. so if you use a
number of LED's in the panel each must have a resistor in series with
it.
simple enough isnt it.

Stealth Pilot

Stealth Pilot wrote:
On Thu, 07 Jan 2010 15:39:13 -0500, Charlie Smith
wrote:

Jim,

From info I have located on the internet, I have cobbled together a
circuit diagram for illuminating my instrument panel using LED's. I was
wondering if I emailed you a copy, would you would be kind enough to
take a peek at the circuit and see if I missed anything? Electronics
isn't my expertise but I enjoy it all the same.

Thanks in advance,
Charlie Smith

charlie, assuming that you are using a 12 volt bus, all you need to do
to use an LED is put a 680ohm resistor in series with it.
so if you had an instrument that was lit by a small tungsten globe, in
theory, all you need to do is take out the lamp holder and wire in the
led and the resistor in its place. the led should then work with the
original switching.
you need to have a resistor in series with each LED. so if you use a
number of LED's in the panel each must have a resistor in series with
it.
simple enough isnt it.

Stealth Pilot

No, its more complicated than that. I'm building the instrument panel
from scratch with 20 LED's. I have put together a PWM dimmer circuit
that has a built in 5V linear regulator. That way, if the battery
starts to die, I have panel lights down to about 7V on the battery. I
just wanted Jim to look it over and make sure I didn't miss something
obvious. I am quite capable of some bone-head mistakes. I've
bread-boarded the circuit and it works fine (with one LED). But that's
different than flying with it.

Thanks,
Charlie

Stealth Pilot writes:

charlie, assuming that you are using a 12 volt bus, all you need to do
to use an LED is put a 680ohm resistor in series with it.

Huh? You can't generalize about LEDs like that! There are many different
LEDs with different electrical characteristics. Given the OP's post,
you can't even state that a simple resistor is what he wants; he may
want variable lighting, in which case a potentiometer is what's needed.

If the OP doesn't get a reply from Weir, I suggest the Matronics
AeroElectric list at http://forums.matronics.com/viewforum.php?f=3

--
Too bad you can't just grab a tree by the very tip-top and bend
it clear over the ground and then let her fly, because I bet
you'd be amazed at all the stuff that comes flying out.
- Jack Handey

On Fri, 08 Jan 2010 16:54:14 -0800, Bug Dout
wrote:

Stealth Pilot writes:

charlie, assuming that you are using a 12 volt bus, all you need to do
to use an LED is put a 680ohm resistor in series with it.

Huh? You can't generalize about LEDs like that! There are many different
LEDs with different electrical characteristics. Given the OP's post,
you can't even state that a simple resistor is what he wants; he may
want variable lighting, in which case a potentiometer is what's needed.


I can state what I like. it is a free society.
what I wrote works for me.
ymmv
Stealth Pilot

"Stealth Pilot" wrote in message
...

I can state what I like. it is a free society.

Yes you can. Even if it happens to be wrong.

Vaughn