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"Light" sleeper

Michail

How would ebay item 180516094665 work out as a clock in someone's house.

Nope, No nixie, but unique.

Michail

--- In NEONIXIE-L@..., "Steve" <NEONIXIE-L@...> wrote:

Threeneurons stated:

Note the circled item on the floor. I have much more respect for Rand,

after seeing that one.

Note what is under the "circled item" on the floor - such is typically used
to assist with "customizations" in conjunction with the circled item.

Also in the scene, but not visible in the picture - the operator's steel toecap boots

[edited by A.J. - please trim quoted material]
On 27 August 2010 06:45, threeneurons <threeneurons@...> wrote:

Here are a couple of photos from a book about the Rand Corporations early
use of computers.

<snip>

Note the circled item on the floor. I have much more respect for
Rand, after seeing that one.

<snip>

And what about the carpenter's saw on the other desk. I always do my
debugging with Grandad's old toolkit.


--

Tom Harris <celephicus@...>


[Non-text portions of this message have been removed]

"per.zapro" <per.zapro@...> wrote:

Hi Group.

I have designed a PCB around Hans' Nixie multimeter design :

I'm curious why Hans turned it into a direct drive circuit. The CA3162 already outputs its data in a multiplexed format, and the timing, from what I can get out of the datasheet, seems plenty slow enough to run nixies without any problem. If he went mux'd, he would have needed only one 74141, instead of 3. He wouldn't needed the 7475 latches, and the 7404 hex inverter. That's 6 extra chips.

Instead the muxing would have needed 3 MPSA42s (or MMBTA42; SOT23), 3 MPSA92 (or SOT23 equiv), and 11 extra resistors (3 per digit, plus a common 2R divider). You connect the A42s in a 'common base' fashion, to deal with the phase of the anode drive outputs (MSD, NSD, & LSD), which are active low. Tie the emitter of each A42 to its corresponding output. Tie all the bases (of the A42s) to the tap of the divider. Uses 2 1Ks off of +5V to Gnd, so the tap is +2.5V. Tie the collectors of the A42s thru a resistor (220K-470K) to the base of its corresponding A92. Connect a 10K resistor (3x) across the base to emitter of each A92, to speed it up. Connect the emitter of all three A 92s to your nixie B+ (180V-200V). The collector of each A92 then ties to the corresponding anode resistor (in existing circuit) of each nixie tube. And there you have it.

For newbies, and the old farts that have been programming too long, you have to remember with transistors (and tubes, too), there are three different hookups in your toolbox:

(1) The 'common emitter', which most of us are familiar with, where the emitter is at a fixed point (usually gnd for NPNs, and a positive supply for PNPs), the base gets the input signal, sometimes thru a base resistor, and the collector is the output. It has both voltage gain and current gain, but the signal is inverted.

(2) Emitter follower (aka Common collector) where the collector is tied to a fixed point, the base is still the input, but now the emitter is the output. Its called an 'emitter follower', for a reason. The emitter output follows input signal at the base, with NO voltage amplification. That means if you tie the collector to +12V or +180V, and the signal fed to the base goes from +1V to +6V, and back again, the emitter will follow the base, less the Vbe drop (~0.6V for silicon at 25C), from 0.4V to 5.4V, and back, as long as the collector voltage is over 7V or so, or a lot more , like +180V. An emitter follower, however, does have current gain, so the input need only supply 1mA, for a 100mA load on the output (given a beta of 100 for that transistor). Its basically at the heart of those common 3 pin regulators, like the 7805.

(3) Finally, the common base configuration. This one isn't seen too often, unless you deal with RF circuits. It does still have its place in digital circuits. In this arrangement, the base is tied to a fixed point, and the signal is fed the emitter. The output comes out of the collector. This circuit has no current gain, but can have voltage gain, and that output signal is in phase (not inverted) from the input signal. It can save you from throwing in an extra inverter package. I also use a common base stage to read the K0 output (NDX or index) from my dekatron circuits, where the cathodes are all tied up to ~60V, but the uC needs a signal between 0V to no more than 5V.

Also, the key to charlieplexing with transistors, is to combine the 'common base' with the 'common emitter' hookups, and get a matrix where you can get "n^2-n" outputs with 'n' I/O signals. That's 6 out with 3 I/O, 12 out with 4I/O, 20 out with 5I/O, ... . Of course, only one output ON at any one time.

--- On Thu, 8/26/10, Steve <NEONIXIE-L@...> wrote:
Threeneurons stated:

Note the circled item on the floor. I have much more respect for Rand,

after seeing that one.

Note what is under the "circled item" on the floor - such is typically used
to assist with "customizations" in conjunction with the circled item.
---

There's also a wood saw on the table behind him in our foreground.


[Non-text portions of this message have been removed]

Threeneurons stated:

Note the circled item on the floor. I have much more respect for Rand,

after seeing that one.

Note what is under the "circled item" on the floor - such is typically used
to assist with "customizations" in conjunction with the circled item.

Here are a couple of photos from a book about the Rand Corporations early use of computers. One shows Johnivac, the only computer to use RCA's Selectron memory tubes (as opposed to common 'Selectron brand' radio tubes, made by RCA). The other shows an analog computer in use. Note the circled item on the floor. I have much more respect for Rand, after seeing that one.




Here are a couple of links on analog computers and Selectron memory tubes if catches your interest:




Enjoy

--- In NEONIXIE-L@..., "per.zapro" <per.zapro@...> wrote:

I have designed a PCB around Hans' Nixie multimeter design :

The PCB works just nicely, just been mounted on my newly aquired switch mode power supply, but i am having problems with the tubes.

I am using IN8-2 tubes, and have grounded the decimal point on the middle one to make the denoter of XX.X volts.

The problem i have - the transformer i selected for my power supply board for the tubes etc. is only putting out 165V DC after rectification, and that seems a bit low. The lighted cathodes in the tube steal the current from the decimal dot, so it goes out sometimes...

Any good ideas of what i can do ? A capacitor-diode doubler circuit seems a bit overkill, since i will be getting a voltage that is too high...

Maybe i need to redesign the power supply PCB layout ?

I have a proposed PCB layout here:

I have thought about two small PCB transformers, back to back to get around 230V to the tubes instead. I just had a bunch of these nice PCB transformers laying around from an Natural Gas furnace, with a 170V (unloaded) secondary and a 18V one too.

<snip>

Am I correct in thinking that this transformer with 170 V and 18 V secondaries is the one that you're using, but is not providing sufficient voltage? If so, you could wire the secondaries in series to get 188 VAC, which should give you a good 10-15 volts more DC under load after rectification and filtering.

A.J.

On Thu, 26 Aug 2010 01:06:02 -0000
"figureloop" <crobc@...> wrote:

I plan to see what I can do with one in the near future, though. I can't
imagine that they would NOT lend themselves to a nixies/vfd clock, they've
got 2k of flash which is equivalent to Atmel's ATTiny2313. (assuming that
the compiled machine code on the two processors is similar.. I don't
actually know about this). There's not a lot of pins, but that shouldn't be
a crippling problem for anyone that understands shift registers. My biggest
concern about these parts is that they are 3.3v only.. Maybe 3.3v is the new
5v? Time to start designing boards around 3.3v, I guess.

I get mine in a 2 weeks delay (here in France). I managed to get the stuff working
but I get some errors w/ the serial driver on Linux. (works randomly) so this
plate-forme is not usuable for me right now.

For the 2k of flash. My first VFD clock run a Tiny2313, so this shouldn't be an
issue. (I know 8bits flash != 16bits ..)

Here the diagramme ..



Bye
--
Jkx <Jkx@...>

Hi Group.

I have designed a PCB around Hans' Nixie multimeter design :

The PCB works just nicely, just been mounted on my newly aquired switch mode power supply, but i am having problems with the tubes.

I am using IN8-2 tubes, and have grounded the decimal point on the middle one to make the denoter of XX.X volts.

The problem i have - the transformer i selected for my power supply board for the tubes etc. is only putting out 165V DC after rectification, and that seems a bit low. The lighted cathodes in the tube steal the current from the decimal dot, so it goes out sometimes...

Any good ideas of what i can do ? A capacitor-diode doubler circuit seems a bit overkill, since i will be getting a voltage that is too high...

Maybe i need to redesign the power supply PCB layout ?

I have a proposed PCB layout here:

I have thought about two small PCB transformers, back to back to get around 230V to the tubes instead. I just had a bunch of these nice PCB transformers laying around from an Natural Gas furnace, with a 170V (unloaded) secondary and a 18V one too.

I know that putting a resistor on each cathode on the nixie would possibly solve the problem, but im not going to make new PCB's again (already on revision 2, since i swapped all connections on the nixies (0 to 9 etc :-O - dangerous stuff when you design two pcb's apart, haha)

TIA.

// Per.

--- In NEONIXIE-L@..., "figureloop" <crobc@...> wrote:

Hi:

Any experience with these? I'm considering getting a few, to make a 4-digit HH:MM and getting 2 smaller less costly numitrons for SS in a 6-digit clock.

Can anyone vouch for their longevity?

I'll take that as a "no."

I will share my experiences once I get some and tinker with them.

--- In NEONIXIE-L@..., Adam Jacobs <jacobs.adam@...> wrote:

On Tue, Aug 24, 2010 at 8:57 PM, <michail1@...> wrote:

In a message dated 8/24/2010 8:12:05 P.M. Pacific Daylight Time,
joseph@... writes:

I'm sure many in the group are aware of the incredible bargain Texas
Instruments is currently offering on their MSP430 Launchpad development
board.

Were that I an accomplished programmer - especially in C which is the
language the TI compiler uses.

Has anyone in the group developed a nixie or VFD clock with the MSP430 as
its heart? Does the MSP430 lend itself to a project such as a clock?

I am still wondering if anyone has received them.

I ordered them two months ago and still haven't received them.
Same for the chronos watch.

Mine arrived a couple days ago, I haven't had a chance to do more than
install their compiler/IDE.
I plan to see what I can do with one in the near future, though. I can't
imagine that they would NOT lend themselves to a nixies/vfd clock, they've
got 2k of flash which is equivalent to Atmel's ATTiny2313. (assuming that
the compiled machine code on the two processors is similar.. I don't
actually know about this). There's not a lot of pins, but that shouldn't be
a crippling problem for anyone that understands shift registers. My biggest
concern about these parts is that they are 3.3v only.. Maybe 3.3v is the new
5v? Time to start designing boards around 3.3v, I guess.

-Adam

MSP430 is a 16-bit architecture, unlike 8-bit AVRs and PICs, so the machine code is completely different. Probably not much different however in terms of code space needed to get a given job accomplished.

A few years past I spent a significant amount of time researching microcontrollers to use for projects at the laboratory where I work. I also hoped to have my decisions cross over to my hobbies.

One of the main considerations was not monetary cost of development boards or processors, but rather, whether or not a fully functional development toolset could be installed without paying in excess of $500.

The AVR was the best choice for 8-bits, since a free toolset was available. PIC was rejected because I started learning about uCs on PICs, and rapidly came to the conclusion that AVRs were easier to program in assembly if need be, as well as being much more suitable for C.

I looked at 16-bit offerings such as Hitachi H8, and the MSP430 at the time which had less choices. It seemed to be that for the MSP430, the peripherals were not as useful to general purpose projects that I was envisioning compared to AVR. The MSP430 is really targeted at low power applications. Since I rarely care about that, the AVR is preferable. Also, the prime criteria of a free toolset was not the case for MSP430. I'm not sure what the situation is now.

Another consideration was learning curve. Since I employ a uC now and then rather than programming them 8 hours a day, I want to have as few learning curves as possible. Everything that needs to be learned, from the tools, to the core architecture, to the peripherals, is a time investment. I think I am more productive using the processor I know today than learning another processor just because it's got a $5 dev. board. Besides, running a bare AVR on a breadboard is just as workable. The only real investment is the initial programmer. And those are certainly obtainable or home-made for cheap.

I decided to skip 16-bits and settle on just an 8-bit AVR for "low processing power" projects, and the TI TMS320F2812 32-bit digital signal controller for high-powered projects. That I use mainly at work, and paid the $500 for the dev. software. Fortunately I can install a second time on my home PC, so as long as I'm not doing anything commercial with that, I get to play with a 150MHz 32-bit uC for cheap as well. I think I got a complimentary Spectrum Digital dev board for that, which is ordinarily not cheap.

I have a co-worker who is trying a new uC every month. I simply don't understand that strategy. Unless there is a hardware feature that I simply must have that isn't in the uCs I know, it is generally not worth the investment to figure out a new chip rather than figure out how to adapt the one I know to do the job at hand.

--- In NEONIXIE-L@..., michail1@... wrote:

I am still wondering if anyone has received them.

I ordered them two months ago and still haven't received them.
Same for the chronos watch.

I imagine the response was overwhelming, considering the $4.95 or so price.

I placed my order through Mouser about two months ago, since the TI order page was not working that particular night. I received my two boards within two days of their TI release date. I guess I was one of the lucky ones. Unfortunately, other than running the temperature demo preprogrammed on the board, all I've been able to accomplish on my own is blink the LEDs.

A colleague at work got the chronos at a TI MSP430 seminar a few months ago in Salt Lake City. I believe it was either an attendance gift else sold for 1/2 price at the seminar. Unfortunately, TI has another MSP seminar in Salt Lake next month during the time I'm scheduled to attend a two week training class with Motorola in Chicago. I'm trying to convince another coworker to go to the TI seminar and pick up the free goodies! :-)

Joe

On Tue, Aug 24, 2010 at 8:57 PM, <michail1@...> wrote:

In a message dated 8/24/2010 8:12:05 P.M. Pacific Daylight Time,
joseph@... writes:

I'm sure many in the group are aware of the incredible bargain Texas
Instruments is currently offering on their MSP430 Launchpad development
board.

Were that I an accomplished programmer - especially in C which is the
language the TI compiler uses.

Has anyone in the group developed a nixie or VFD clock with the MSP430 as
its heart? Does the MSP430 lend itself to a project such as a clock?

I am still wondering if anyone has received them.

I ordered them two months ago and still haven't received them.
Same for the chronos watch.

Mine arrived a couple days ago, I haven't had a chance to do more than
install their compiler/IDE.
I plan to see what I can do with one in the near future, though. I can't
imagine that they would NOT lend themselves to a nixies/vfd clock, they've
got 2k of flash which is equivalent to Atmel's ATTiny2313. (assuming that
the compiled machine code on the two processors is similar.. I don't
actually know about this). There's not a lot of pins, but that shouldn't be
a crippling problem for anyone that understands shift registers. My biggest
concern about these parts is that they are 3.3v only.. Maybe 3.3v is the new
5v? Time to start designing boards around 3.3v, I guess.

-Adam

I'm sure many in the group are aware of the incredible bargain Texas Instruments is currently offering on their MSP430 Launchpad development board.

Were that I an accomplished programmer - especially in C which is the language the TI compiler uses.

Has anyone in the group developed a nixie or VFD clock with the MSP430 as its heart? Does the MSP430 lend itself to a project such as a clock?

Joe

I am still wondering if anyone has received them.

I ordered them two months ago and still haven't received them.
Same for the chronos watch.

Michail

Take a look at this one, it's very similar to what I see:


A.J.

I found the culprit!

<!--[if lt IE 7]>
<style type="text/css">
html
{
display:none;
}
</style>
<script type="text/javascript">
(window.prompt('Please get a new browser!',''))
location.href='';
</script>
<![endif]-->


I am using a Joomla theme I purchased from ThemeForest.net for the site. The original author added that less-than-friendly code in the index.php file.

Brian

Take a look at this one, it's very similar to what I see:


A.J.

Hmm. I didn't actually put that message there, but I am guessing that the chat software I had installed may have been doing that. I removed the potentially offending code. Let me see if I can find an older version of IE and give it a try.

Brian

[edited by A.J. - please trim quoted material]
On Sun, Aug 22, 2010 at 9:47 AM, mimewar <mimewar@...> wrote:

--- In NEONIXIE-L@..., "mimewar" <mimewar@...> wrote:

I had a working one tube counter, a simple 0-9. I was using the Basic
Stamp board. I moved to a Picaxe 08M, and now, it won't count past 7. I goes
0,1,2,3,4,5,6,7, dark, dark, 0,1,2,3,4...

Anyone have any experience with the 74141 TTL chips and microcontrollers?
Did I leave something tiny, but important out? I have the four output pins
of the 08M, going directly to the 1,8,2,4 inputs of the 74141 ( and yes I
made sure about 12 times that the outs and ins all correspond.. No caps, no
resistors except on the HV input on the tube..

<snip>

I added a LED from pin 4 to ground to test the circuit. 8 and 9 now work,
so i suspect the Picaxe I am using is supplying an overvoltage, about 2.3V
too much. Anyone care to confirm?

Ah-ha! That behavior smells exactly like the chip lacks a pull up on that
pin. I looked it up and the PICAXE 08M is just a preprogrammed PIC12F683.
Pulling up the datasheet for that chip (
). Page 33 of
that document tells me that, indeed, the chip lacks a pull up resistor when
that pin (GP3 = physical pin 4) operating in IO mode. The datasheet specs
that pin as only for input, so the easiest solution would be to use that pin
as an input and pick some other pin to drive your high order bit. If you
must use that pin, you can probably simply use a pull up resistor -- a
resistor on the order of 10k tied from the pin to VCC (then connect to the
pin normally -- make sort of a T). I've never heard of a diode being used as
a pull up (push up?) like you did, but I'm pretty sure that's how it's
working now. I actually got a hold of a picaxe for the first time ever this
weekend, so I'm sure someone more experienced could chime in...