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'scope clock advice please

Well, I've been gone for a month and this group is dead. So maybe my questions will liven it up some. Or maybe everyone else is also on vacation. I know, this is a repair group. But I will no doubt need to repair whatever I build. And besides, I get better electronics advice here, as in more of it and correct, than on the basics group. While wasting some time on the computer while being on hold I came across some small ocsilloscope CRTs, then looking for something to light one of them up I saw some kits to make oscilloscope clocks. Only

34 bucks for the kit! So I ordered a two inch CRT with electrostatic deflection. Here's a link to the CRT I ordered:
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Then on to ordering the kit. Hah! No dice. The kits are no longer available. But I think I can still download the code for the microcontrollers and the files for the circuit boards. Here is a link to the page that the kit used to be available from:
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The kit was also available from other sources but I can't find it for sale anywhere. Darn. Maybe someone here bought one of these kits and never built it and it is collecting dust. If so why not sell it to me? I also need to drive the CRT and I found a simple circuit called the Mullard's Pupil Oscilloscope. Here's a link:
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So, if I build the Mullard scope circuit will it drive the two inch CRT I ordered seeing as how it was made to drive a 1 inch CRT? And if that works will the Dutchtronix clock circuit work with the Mullard scope and give me a nice looking display? Look, this is just for fun. I am capable of safely dealing with the high voltage. But I don't know enough to know if all the parts will play nice with each other. I have also not built any tube or valve gear using point to point wiring so a little advice about that would be greatly appreciated. When it is all done the idea is to have as much of the tube circuitry as possible exposed with the modern microntroller stuff hidden away. I like tube stuff and exposed machinery, always have. I think a one tube scope with a hand wound xmfr could look pretty cool sitting on a shelf near my tube amplifier. Thanks All, Eric
Reply to
etpm
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Maybe. :-)

In principle it ought to work, if you get the voltages correct. If you don't, it'll either not work, or damage the CRT or something else.

Among the things you'll need to look at, in matching up the various circuits and components, are;

- The required heater (filament) voltage and current for the CRT you are using.

- The cathode, grid and deflection voltages for the CRT you are using.

- The voltages being created by the clock circuit (microprocessor) and being fed to the X and Y inputs of the scope circuit

Read through the data sheet for the DH3-91 CRT that the circuit was designed to work with

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and for the CRT you bought.

The physical size of the CRT doesn't matter very much (directly) but a larger or different CRT may have different voltage or current requirements.

Reply to
Dave Platt

Looks like a fun project! Make some PCBs and offer them here, I'd probably buy one just for fun. I've got a few 'scopes sitting around that aren't doing anything useful...

As for the Mullard scope, it should work with a larger tube, you just may have to raise the deflection voltage a bit. Find the specs on the two tubes to see what the deflection differences are - if any!

John :-#)#

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Reply to
John Robertson

** No pics or diagram showing up for me.

Am I missing something?

.... Phil

Reply to
Phil Allison

Might pay to check around, comes up OK for me in Oz

Reply to
Rheilly Phoull

Loads fine here(Netherlands). Interesting circiut diagram. Needs a few mods, if you dont want a 12v supply.

Reply to
Sjouke Burry

** Sites sometimes tell me I am using an "ad blocker" - which must be part of Windows 7 cos I never added one.

Could that be it ?

.... Phil

Reply to
Phil Allison

I doubt it. I am using an adblocker and see the page without problem. I don't know what browser you are using, but try using it with all add-ons disabled ("Safe Mode" when using Firefox, for instance). If that allows you to see the page, you have to go back to normal mode and switch each off add-on in turn until you find the one which is stopping the page from displaying.

--

Jeff
Reply to
Jeff Layman

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Peter Wieck Melrose Park, PA

Reply to
peterwieck33

Odd.. You can try converting the web page to a .pdf right on line. If you can open this:

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or one the many like it, input the instructables url and it will convert it to .pdf.

Reply to
John-Del

nd a simple circuit called

Works fine for me in Vancouver, BC...

Nice schematics with valves instead of tubes. Must be some furren idear.

John ;-#)#

Reply to
John Robertson

Works fine here in NZ and I'm using an adblocker AND an anti-tracking add-on (Privacy Badger, I recommend it highly) in Firefox, works in Chrome too.

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Shaun. 

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in the DSM" 
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This is not an email and hasn't been checked for viruses by any half-arsed self-promoting software.
Reply to
~misfit~

Based on all the successful responses, the answer is obviously "YES!"

Reply to
jfeng

Hi Phil,

I use this site when I'm not sure where the problem is:

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Hope that helps!

John :-#)#

Reply to
John Robertson

Thanks Dave. I downloaded the datasheet for the Mullard tube and I'll compare it to my CRT when it arrives. Eric

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Reply to
etpm

I have seen both links. The top one charges $100.00 plus shipping for the kit minus a CRT. I may go this route. The bottom link is to the kit that is no longer available. But I can download the files for the PC boards and the code for the microcontrollers. I did mention this in my post. Eric

Reply to
etpm

Yeah, I saw that kit. $170.00 and he doesnt't even show a picture of the clock display. It's too bad I didn't think about doing this a few years ago when a board could be had for $34.00! Eric

Reply to
etpm

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