| Author |
Message |
|
|
 Posted: Feb 27, 2006 - 07:09 PM |
|
Joined: Jan 03, 2006
Posts: 4417
Location: Hemel Hemsptead, UK
|
|
And those of us in NeoNixies are very happy about it... As far as is known, and it's a regular question on the forum, there are no new nixies being made - it's all NOS or even old old stock. A lot is recycled from the odd bits of equipment that pops up and often the second-hand stuff is past its useful life.
The tubes on my clocks are ZM1210 - I get them from Jan at Ask Jan First in Germany; they're inexpensive and I like the look of them. A lot of the Russian tubes do things like turning the 2 upside down to make the 5, which I don't like the look of.
Neil |
_________________
Neil Barnes
www.nailed-barnacle.co.uk
|
| |
|
|
|
|
|
|
Posted: Feb 28, 2006 - 02:16 AM |
|
Joined: May 26, 2004
Posts: 2538
Location: Las Vegas, Nevada
|
|
Here's my version of a Nixie clock. It uses Burroughs B7971 tubes that were originally made for the ticker at NYSE. When the old ticker was torn out, some enterprising individual grabbed all the tubes and kept them in a warehouse for about 25 years. They were quite common on ebay a couple of years ago, but very hard to find now. These are well hammered - see the grey cathode material sputtered on the support insulator - but they still work very well.
Actually it's not just a clock, it's a Four Letter Word generator. It displays four letter words at random every few seconds and the time once a minute. The heart is a Mega168, which has just enough room for the display program and a 3,300 word dictionary. There's a Dallas DS1307 RTC on the TWI, and the display driver is the square chip in the middle, a Supertex HV shift register running off the SPI. |
|
|
| |
|
|
|
|
|
|
Posted: Feb 28, 2006 - 07:31 PM |
|
Joined: Jan 03, 2006
Posts: 137
|
|
Ok, don't laugh, it's not much compared to some of the projects I have seen, but I have learned a great deal about the AVR in doing it. I programmed it in both C and assembler. I used an LM34DZ as the temperature sensor.
Ed
[/img][/url] |
|
|
| |
|
|
|
|
|
|
Posted: Feb 28, 2006 - 08:41 PM |
|
Joined: Apr 16, 2001
Posts: 3522
Location: Phoenix, Arizona
|
|
Edhill,
While it won't pass the "Gwen" standard for breadboarding, it's still quite an accomplishment to read the sensor and talk to a display. Wait till the end of the semester and see how many questions we'll get asking how to do your exact project! |
|
|
| |
|
|
|
|
|
|
Posted: Mar 01, 2006 - 06:10 AM |
|
Joined: Jan 23, 2004
Posts: 9826
Location: Trondheim, Norway
|
|
edhill,
I actually like your breadboard - it has character. It reminds me of my own breadboards, and for that matter programming! It works, and YOU know where all the wires go and what they do, so why should people complain?! 
That's a very nice LCD - very readable. Might I inquire where you got it?
Project image added to the gallery.
- Dean  |
_________________
Atmel Studio 6.1 is now released, grab it here.
Report AS6/ASF bugs here.
|
| |
|
|
|
|
|
|
Posted: Mar 01, 2006 - 06:22 AM |
|
Joined: Mar 28, 2001
Posts: 20363
Location: Sydney, Australia (Gum trees, Koalas and Kangaroos, No Edelweiss)
|
|
Dean, as an Administrator now you will have to get some artistic person (Gwen??) to come up with a respectable Avatar, at least wear a tie above the Butterfly  |
_________________
John Samperi
Ampertronics Pty. Ltd.
www.ampertronics.com.au
* Electronic Design * Custom Products * Contract Assembly
|
| |
|
|
|
|
|
|
Posted: Mar 01, 2006 - 06:40 AM |
|
Joined: Nov 17, 2004
Posts: 13840
Location: Vancouver, BC
|
|
|
Quote:
That's a very nice LCD - very readable. Might I inquire where you got it?
I've seen lcd displays like that at 411 Tech Systems. They have 2 line and 4 line models. I've bought stuff from them before. They have pretty good prices and great service. |
_________________
Regards,
Steve A.
The Board helps those that help themselves.
|
| |
|
|
|
|
|
|
Posted: Mar 01, 2006 - 06:50 AM |
|
Joined: Jan 23, 2004
Posts: 9826
Location: Trondheim, Norway
|
|
|
js wrote:
Dean, as an Administrator now you will have to get some artistic person (Gwen??) to come up with a respectable Avatar, at least wear a tie above the Butterfly
Hmmm. I actually liked my ButtLoad avitar, but a RayKAvr complained, so I need a new one. If anyone DOES have any proper suggestions so that my avitar fits into a "...forum devoted to successful professional or hobbyist use" i'd like to hear/see them.
- Dean |
_________________
Atmel Studio 6.1 is now released, grab it here.
Report AS6/ASF bugs here.
|
| |
|
|
|
|
|
|
Posted: Mar 01, 2006 - 08:18 AM |
|
Joined: Sep 10, 2005
Posts: 459
Location: Louisiana,USA
|
|
| I've noticed that the album 'Butterfly Play Thing' has disapeared....... |
_________________
My AVR Site
|
| |
|
|
|
|
|
|
Posted: Mar 01, 2006 - 08:22 AM |
|
Joined: Jun 27, 2005
Posts: 3412
Location: St.Petersburg, Russia
|
|
Just in case someone has missed my first AVR project, here's the pic:
It's a two-wheel balancing robot. Ditched now, couldn't make it balance well enough. But it was great fun to play with and its board still lives and serves for experiments. There's an ATmega32 in there.
It balanced better before upgrading to Advanced Security Technologies (see pic). They are too heavy. |
_________________
The Dark Boxes are coming.
|
| |
|
|
|
|
|
|
Posted: Mar 01, 2006 - 09:20 AM |
|
Joined: Jan 03, 2006
Posts: 4417
Location: Hemel Hemsptead, UK
|
|
Hey, I did balancing robots in the Mechatronics module of my BSc... which algorithm did you use? I recall being most unimpressed that a Bang-bang system had better performance than fuzzy, proportional, or indeed any of the other options available.
In our case, we had to balance a stick above a moving cart, constrained to move in one axis only. Kind of like balancing a pencil upright on your finger.
Neil |
_________________
Neil Barnes
www.nailed-barnacle.co.uk
|
| |
|
|
|
|
|
|
Posted: Mar 01, 2006 - 09:39 AM |
|
Joined: Mar 07, 2001
Posts: 2376
Location: Stockholm, Sweden
|
|
|
Quote:
It balanced better before upgrading to Advanced Security Technologies (see pic). They are too heavy.
Ahhh! FINALLY some use for those about 1000 obsolete MSDN CD's that I have here !
I noticed you have used the Swedish version of the discs. No wonder they're too heavy! |
_________________
/Jesper
http://www.yampp.com
The quick black AVR jumped over the lazy PIC.
What boots up, must come down.
|
| |
|
|
|
|
|
|
Posted: Mar 01, 2006 - 10:47 AM |
|
Joined: Jun 27, 2005
Posts: 3412
Location: St.Petersburg, Russia
|
|
@Neil: I measured tilt with dual axis accelerometer (no gyros). Used a simple PID loop to compensate the position. I don't know what is really at fault (I guess my loose brain being not the least important factor). But the motors I used are very slow, I just don't think they'd be capable of rolling my platform fast enough. They were only good to keep it standing in balanced position, but this is not real balancing -- add a pole and it falls. What's a Bang-bang system?
@Jesper: Advanced Security Technologies are truly international though, it just happened so that Swedish disc is on the outside. |
_________________
The Dark Boxes are coming.
|
| |
|
|
|
|
|
|
Posted: Mar 01, 2006 - 01:07 PM |
|
Joined: Jan 03, 2006
Posts: 4417
Location: Hemel Hemsptead, UK
|
|
Bang-bang servo control just takes a constant impulse and applies it in the direction that the stick is falling, in ths case to move the cart under the stick. I don't recall all the details at this point - too long ago - but it worked remarkably well. There's no attempt at proportional control.
Neil |
_________________
Neil Barnes
www.nailed-barnacle.co.uk
|
| |
|
|
|
|
|
|
Posted: Mar 01, 2006 - 01:37 PM |
|
Joined: Jun 27, 2005
Posts: 3412
Location: St.Petersburg, Russia
|
|
Oh. Bang-bang.. I guess it has something to do with motor nonlinearity, maybe that's why? I tried to add some ad hoc compensation stuff into my PID loop to increase stability near vertical point.. But no matter what I did I could not make it run fast enough to stop once it has begun falling -- it would just roll away, then bump into something and sometimes stand back after that. Sometimes, start rolling in opposite direction. It was fun to watch  |
_________________
The Dark Boxes are coming.
|
| |
|
|
|
|
|
|
Posted: Mar 01, 2006 - 02:46 PM |
|
Joined: Nov 10, 2005
Posts: 1527
Location: Redmond, WA
|
|
|
Quote:
I've noticed that the album 'Butterfly Play Thing' has disapeared.......
It's back, and more in the top level zoom album. |
|
|
| |
|
|
|
|
|
|
Posted: Mar 03, 2006 - 02:28 AM |
|
Joined: Aug 04, 2005
Posts: 1267
|
|
Here is my latest incarnation of my ac/dc square-wave pulse generator.
I have got the parts down to nearly nothing...waveforms are programmed
in using a phototransistor mounted through the case and then held up to
a PC screen while a program sends the data over as a series of light
flashes.
This has a bridge circuit in it and can be powered by any well-isolated
dc or ac source 9v to 25v.
This is just a project to try out new ideas...it is not for any use other than
experimental
:note the use an 18pin IC socket as a socket for 6 small transistors.
This works great and takes many insertions without giving a loose
contact...it's great if like me you keep smoking your transistors.
When I finally am satisfied with my design I am going to have some
boards made at sparkfun to make it look more professional.
This project looks kind of lame up against some of the really advanced
ones posted here..but this is my skill level and I'm proud of it |
|
|
| |
|
|
|
|
|
|
Posted: Mar 03, 2006 - 05:17 AM |
|
Joined: Dec 01, 2003
Posts: 2502
|
|
|
Quote:
This project looks kind of lame up against some of the really advanced
ones posted here..but this is my skill level and I'm proud of it Smile
Not lame at all, and you should be proud! Controlling a device by coded screen flashes
sounds pretty darn clever to me. The only devices I recall that made any use of monitor
light emissions (besides actual eyeballs) were "light pens". In Tulsa, there are photoelectric
pickups on top of traffic signals that respond to coded flash sequences from strobe lights
mounted on ambulances and fire trucks. The traffic lights then respond to flush the intersection
in front of the advancing emergency vehicle. Simple and effective, I wish I had the patent on that
"lame" little gadget!
Tom Pappano
Tulsa, Oklahoma |
|
|
| |
|
|
|
|
|
|
Posted: Mar 03, 2006 - 02:38 PM |
|
Joined: Nov 17, 2004
Posts: 6137
Location: Great Smokey Mountains.
|
|
Gwen: I've got a Timex watch with MicroSoft software on it that programs the watch by flashing the PC screen. I've often wondered how they control the timing on the flashes since Windows is indeterminate and can go off and do God-knows-what right in the middle of any time critical function you write. It is the exact opposite of a real-time system. So how do you plan to time the output pulses? I know it can be done, because my watch software does it, I just don't know how they do it.
Smley |
_________________
FREE TUTORIAL: 'Quick Start Guide for Using the WinAVR C Compiler with ATMEL's AVR Butterfly' AVAILABLE AT: http://www.smileymicros.com
|
| |
|
|
|
|
|
|
Posted: Mar 03, 2006 - 10:24 PM |
|
Joined: Jan 23, 2004
Posts: 9826
Location: Trondheim, Norway
|
|
I'm sure you'll both be interested in the "Silicon Wallet" project by Alberto Ricci Bitti (http://www.circuitcellar.com/library/print/1005/Bitti183/index.htm). He uses a photosensor to download passwords into his device via coded flashes from a webbrowser. Neat design - he got a good placing in the Circuit Cellar competition I believe. One of his design toubles was getting the device to work with both CRT and LCD screens, since they are totally different in their peaks from one another.
- Dean |
_________________
Atmel Studio 6.1 is now released, grab it here.
Report AS6/ASF bugs here.
|
| |
|
|
|
|
|
FAQ
Search
Register
Log in to check your private messages
Log in
Maximize
RSS
