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If anyone has this chip, on hand, please build up the circuit on the last page of the datasheet, and report back to us. I hate to burst anybodies bubble, but I see a problem.

With so many tried & true, tested, and readily available methods out there, I don't think I'll ever understand why people bother hacking around with inferior and hard to find IC's, unless they already happen to have the IC and wish to do something interesting with it.

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

Beauty is in the eyes of the beholder. In the 70's when this tube was first used as a clock display only TTL logic chips were available and a 7 segment number display was the norm even for LEDs. I personally find the 7 segment look to be clean, simple and very retro. The other number permutations utilizing the additional segments seem strange and unfamiliar. To each his/her own I guess.

True 7 segment displays are tilted a bit which IMO makes the appearance a lot more attractive, the 14 segment "union jack" is straight up and down and looks weird and boxy when only driven as 7 segments. The datasheet for these tubes includes a nice attractive font which has numerals easily differentiated from the alphabetical letters it can also display. It was not too hard to do this even back in the 70s, Ray used diode decoders in his FLW box, and one could build a decoder easily enough from TTL logic. Unfamiliar is one of the great things about these tubes, they stand out and are unlike just about anything else out there.

--- In NEONIXIE-L@..., westdave <WESTDAVE@...> wrote:

the best way i have found to DRIVE the projection displays is a cd4028 decade counter decoder driver & 2x uln2003 transistors in 16 pin dip, it take's BCD code also a good trick is to drive the lamps at 12volts if thats what there design is? and use a 12vdc to 5 vdc voltage converter and run the logic on the 5 vdc and the lamps at 12vdc

Isn't there a 74xx series IC that is a BCD to 1-of-10 decoder with open collector outputs just for this sort of thing?

They can be multiplexed nicely too without side effects but you do have to put a diode in series with each lamp.

The lamp voltage varies, 5V, 12V, 28V, and likely others were available.

The answer to that?
Why! A Tek 464 / 466 of course! I know Storage CRTs have pitfalls of their own, the least of them being that the tubes are made of an unobtanium isotope, but that what even quantities were made for! (I have 2, and specifically bought that model as many in the group have confessed, out of the "first love" experience).
I have also worked with DSOs in the past, old ones but DSOs anyway and not toys. They do allow detailed analysis, plus have some other functions that analog scopes don't even dream to have.
But similar things go together so for the digital realm, DSOs seem to be good, however if I suspect a d*rned fast glitch in a digital bus, I won't change my analog scope for anything in the world. After all, at today's switching speeds, square waves simply don't exist.

Well like I said, they both have advantages and disadvantages. If I could only have one, I'd keep the analog scope, but I find having both to be valuable. I often pull out the Tek 465 first to see what's there, then if there's something I want a closer look at, I get out the Bitscope. I did have to build a USB isolator for the Bitscope though, before that I had a lot of problems with the USB locking up due to noise. I don't know why they didn't build an isolator into it, would have been easier to isolate between the USB-serial bridge and the rest of the unit.

--- In NEONIXIE-L@..., Mike Harpe <mike@...> wrote:

I am interested in learning more about the so-called "projection"
displays that were used in a lot of 1970s industrial rack-mount type
clocks.

Does anyone on here have a reference or source for them?

Thanks!

Mike Harpe
Sellersburg, IN USA

They're pretty simple devices. A matrix of miniature incandescent lamps illuminates text printed on photographic film and is focused onto a screen by a matrix of molded plastic lenses. If there was demand, it would be cheap to produce with modern injection molding but you would have to make a LOT of them before the price was reasonable. Unlike Nixie tubes, there is no esoteric equipment or "magical" formulas of materials and gas fill required.

Can someone explain how you would wire this up? I don't quite get it. It's a NC switch and input 3 appears to be the pin that controls if its open. I don't get how I would wire it. Thanks.

datasheet:

Thank you for the update - that is awesome news about the neon! From the
photo on ebay I thought the labeled tube *might* be gassed. I eagerly await
further reports!

Mike

--

www.mikerippe.com

--- In NEONIXIE-L@..., "chuck" <cdale27m@...> wrote:

Hi, I was wondering if anyone has run across a solid schematic for a VU meter based on these tubes. I've found finished projects, but not a good page that goes into build details.

Yes, this AudioXpress article by Joe Sousa has one.



Gaston

Here's a place with lots of info:

Hello Chuck.
Try the second schematic on my site.? f6fkn.com
You'll find what you're looking for, although it's been drawn around a Russian EM84 :6E3P
But you can indifferently use both, without any change inside the circuit.

Sorry, but the English version of this site is not ready yet...

Alain

Here is a quite simple one:

Message du 16/07/10 05:08
De : "chuck"

Hi, I was wondering if anyone has run across a solid schematic for a VU meter based on these tubes. I've found finished projects, but not a good page that goes into build details.

Try the second schematic on my site.? f6fkn.com
You'll find what you're looking for, although it's been drawn around a Russian EM84 :6E3P
But you can indifferently use both, without any change inside the circuit.

Alain

Well I got the tubes from the seller in the mail. Pictures will follow
later.
2 tubes one is unmarked the other is marked in blue with the following
VX9110
DEV LAB SAMPLE
NL
NUMBER 7

It is an end view tube approx 1 5/8 inch dia
by 4.25 inch long

No anode mesh, it has 13 segments formed of wire sitting on top of a
ceramic support plate that sits on top of a mica centering disk. The innes
segmemts are in a star pattern with the vertical ray going from top to
bottom, all other segments make up half sections. Size of the display is
1.125 tall x .75 wide in inches. There are a couple of decimal points?
There are 16 pins. The pins face the front of the tubes. The bakelite
bases are brown and have a finger pull on the back. It looks like the
tubes were made to plug into a panel from the back side of the panel. The
glass press is flat and has 16 wires coming through it. (lookes like the
old style tube press before the wafer seal came into use.) the seal
tubulation comes out through the center of the glass press. There are 2
rectangular getters. Both tubes still contain Neon as they light with my
hand held sparker/tesla coil tester. Have not had time to wire up to a
power supply with the appropriate limiting resistance.

Hi, I was wondering if anyone has run across a solid schematic for a VU meter based on these tubes. I've found finished projects, but not a good page that goes into build details.

Does anyone know where I can source these.

They can drive six B7971 Nixies directly, 12 hour with lead
zero blank, brightness control, date, enable Just add HV power
supply at 170v and you are good to go.

Data sheet uploaded to files section.

If anyone has this chip, on hand, please build up the circuit on the last page of the datasheet, and report back to us. I hate to burst anybodies bubble, but I see a problem.

Primarily, it looks as if this circuit was intended to run small 'panaplex' type 7-seg displays. The segments on these displays usually don't want to see more than ~250uA (0.25mA) of current. Typical 0.6" nixies like between 1 & 3 mA, and the B7971 somewhat more. The chip outputs pulses (on the cathode side) in the 50V transition range. Those pulses are biased to -150V, so the pulse jumps from -150V(off) to -200V(on). That is the -150V to -200V, is the 50V transition. The 50V pulse is also DC isolated from the display thru 0.05uf (lets say 0.047uf) capacitors. The pulse may stay pretty square with 250uA cathode current, but may droop some (or a lot) with 2.5mA (or 5mA) of current. You may need to up those capacitors to 0.22uf to 0.47uf. The 20K Rs may need to be reduced too (?).

Another omission is the multiplexing frequency. They say its done by way of an RC pair tied to pin-20, but they never show a formula, nor curve, on actually determining the target frequency. The values in the circuit (fig 3) are 150K & 0.015uf. If anyone gets the circuit built, throw a scope on that pin an measure the frequency. I'm betting its between 75Hz & 300Hz (closer to 300), from the circuits usually used for this kind of thing.

Here is a page with pictures of a number of projection displays and other displays that use light bulbs. (A shameless plug warning applies, given that I made the page.)



Here is another page which shows several internal photos of a smaller projection display.



Richard Kline
www.decadecounter.com

the best way i have found to DRIVE the projection displays is a cd4028 decade counter decoder driver & 2x uln2003 transistors in 16 pin dip, it take's BCD code also a good trick is to drive the lamps at 12volts if thats what there design is? and use a 12vdc to 5 vdc voltage converter and run the logic on the 5 vdc and the lamps at 12vdc

Just saw this on Hack a Day.

()

... If someone asked, "What does it do?" You can
honestly say, "To make people ask questions."
or "Calculating the meaning of life"

Michail

Calculating the the meaning of life has been done: