Burn-O-Tron Mk1

[juansolo]

The Burn-o-Tron Mk1. Not my tidiest build... Which is a bit of an understatement. I bludgeoned the hole for the display into the case. I HATE cutting square holes. As you can tell from the scratches and the gaping hole above it that's hidden with tape. Then there was that f**king display. The single most illogical pile of shit I've ever purchased! Which is why there's no internal shot... It's been wired and re-wired so many f**king times...
Oh and the Daimler badge is there because I had it and it fit.



Anyhow, burning the 7 right now... On the left is how it looks in my clock. On the right is where it'll sit for a couple of hours until I can back it off and it all stays lit. Limits for the IN-18 are 200V 8mA so 170V and 6mA are nicely within that.

[alparent]

Nice.
I didn't know you needed to burn these in.
Those lamps are cool!.......Or should I say hot?

[juansolo]

Nice.
I didn't know you needed to burn these in.
Those lamps are cool!.......Or should I say hot?

You don't need to burn them in, it's to 'cure' cathode poisoning, which IN-18 nixies are notorious for.

[Timko]

Maybe this is a dumb question (probably so), but what is this thing and what does it do?

[juansolo]

Ok, back home now so I can give a proper reply.

Nixies are 70's tech at best and are idiosyncratic. If it's not problems with the tubes it's problems with the circuits that drive them or a combination of the two.

From what I've built the single only combination I've made with zero drawbacks is the PVE QTC with IN-8-2 nixies. It just works, it's silent (some whine and it drives me up the wall, it doesn't) and the tubes seem pretty consistently good.

The QTC wth the ZM1210 nixies is a thing of absolute beauty. They are by a long way, the prettiest nixies known to man. However there's a bit of conflict of interests and when they've been on for a long time, there's some phantom numbers you get lighting up in some of the tubes. This I think is down to the way the tubes are being driven by the clock (matrixed), but also their nature. I personally can live with it because of just how damn pretty they are, but if they ran with a PIR or were direct drive I suspect those problems would vanish. Though this is speculation on my part.

The Spectrum clocks are the ones that drive the big nixies. The most accessible of which are the IN-18's. The clock itself is pretty much perfect in terms of operation and options. However the tubes are prone to cathode poisoning. By prone, I mean expect it to happen...

Cathode poisoning occurs when contamination of the element, probably introduced at manufacture by poor handling of the cathodes, causes parts of characters to go dark or even go out. This can actually be reversed in a fairly brutal manner by running the contaminated element and higher voltage/current and burning the contaminants off for a couple of hours. Which is what this device I've built is for.

[juansolo]

Cleggy's also going to paint it tomorrow because the scratches and general scruffiness of the thing is bothering me...

[alparent]

Thanks for that explanation.
I've learned something today.

[juansolo]

Better post-tartage.



Internals... Not so pretty...

[Adam_DIY]

Lol I love how your not so pretty internals are tidyier than my better efforts 

[alanp]

I keep misreading the title as "Bum-O-Tron".

Maybe you can use that on the next particularly farty fuzz.

[juansolo]

Sounds like a plan!

[Muadzin]

I've read this thread twice and I still have no clue whatsoever what this thing does. Other then burn something called nixies.

[juansolo]

Nixie tubes are a display element that was used in the 60's and 70's in test equipment and wotnot. The tube in the burn-o-tron for example has digits 0 through to 9 in it. They work like a neon lamp, you run power through the element and the gas around it glows. They're not like thermionic valves in that they don't get hot particularly.

Commonly these days the tubes are used in clocks as they have a very steampunky style. Now as you can't sell the clocks built (Dalibor Farny aside... Pricey!), they're available as kits. Likewise the tubes stopped production in the 70's and go from not a lot to HOW MUCH very quickly.

The problem comes that some of the big tubes (like these ones) are now getting to the £60+ a piece mark. But they are prone to a thing called cathode poisoning. Which is contaminants on the digits causing them to go dark in patches or go out completely. What the burn-o-tron does is over-power the element which burns off these contaminants and restores the digit to it's former glory. The process takes a couple of hours per digit at around 170V and 6mA. But at the end of it they look as good as new.

It's a tad expensive for a clock to be fair... The one below probably cost around £500+ all up when it was finished. Hence you don't want to have to be endlessly splashing out on new (old) tubes in the hope you get a good one.

[Muadzin]

Consider myself enlightened.

I think I saw a clock with tubes like that at a local music store. I thought that was wicked cool, although if I had to splurge money on a music themed appliance I'd get one of those Marshall fridges.

[juansolo]

We did float the idea with Martin of MJW amps of putting some in an amp. We just couldn't think of anything that they could display that'd justify it.