Products > Test Equipment
Kontron/Tabor 6010 universal counter still worth getting?
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Ash:

--- Quote from: 0xdeadbeef on March 01, 2018, 06:31:05 pm ---Wow, thanks, how could I overlook the schematics in the manual? I actually searched for the Jumper 4 layout in the manual but didn't consider that the schematics were only graphics.

--- End quote ---

Haha.. I guess I'm used to looking at old manuals which are scans of a photocopy of a printout...


--- Quote from: 0xdeadbeef on March 01, 2018, 06:31:05 pm ---Anyway, I tend to think that the manual mixes up U56 and U58. While U58 is used in the analog output option, U56 is the 74F132 (Quad 2-input NAND Schmitt trigger) used in the 5ppm Oscillator. It's socketed as all the other ICs and I guess it would make perfect sense that the 5ppm oscillator isn't connected to the device anymore if it's removed.

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Ah yes, makes sense. I didn't have a lot of time to search for it. Now that you point that out, it would certainly make more sense to pull the NAND that is driving the 10Mhz output. Leave the oscillator there as you may need it at some point and that way you won't loose it :)


--- Quote from: 0xdeadbeef on March 01, 2018, 06:31:05 pm ---I originally planned to use one of the 10MHz OCXOs I bought some time ago and I guess I could build some PLL circuit to crank it up to 100Mhz.
The benefit of this approach would be that I could also still use an external 10MHz (keeping the 10x multiplier) reference with an internal jumper.
But it's certainly much easier to try to get a 100Mhz TCXO (or OCXO) with <=1ppm. 
Now this really looks like it could be a piece of cake to build myself a fake option 1...

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That's the wonderful thing about this older gear - its well documented and can be modified and built upon  :-+


--- Quote from: 0xdeadbeef on March 01, 2018, 06:31:05 pm ---[EDIT]
On a 2nd thought, I guess using some off-the-shelf clock multiplier like the IDT ICS601M-01 I could actually re-use my 10MHz OCXO and keep the possibility to use an external 10MHz Reference.
https://www.idt.com/document/dst/601-01-datasheet

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You might want to be careful with that chip - it seems to be designed for direct crystal driving. It also states that the jitter and phase between the reference and output are not specified.

The external input is really useful I think and it is something I'd try to incorporate, but I'd be looking for a higher spec design. The problem is going to be the accuracy of your measurements will be directly affected by the jitter.

Let me know if I can help with anything. I find this lots of fun messing with old gear and I always learn a lot.

Ash.


0xdeadbeef:

--- Quote from: Ash on March 01, 2018, 11:17:07 pm ---You might want to be careful with that chip - it seems to be designed for direct crystal driving.
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It also supports clock in. X2 is just left open then.


--- Quote from: Ash ---It also states that the jitter and phase between the reference and output are not specified.
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It's true true that the input to output skew isn't defined but I'm unsure why I would need that for this application.
Anyway, there is also a "zero delay" version available namely the ICS670 which however has a slightly worse phase noise specification (-124 dBc/Hz at 10 kHz for the 670 vs. -132 dBc/Hz at 10 kHz for the 601).


--- Quote from: Ash ---The external input is really useful I think and it is something I'd try to incorporate, but I'd be looking for a higher spec design. The problem is going to be the accuracy of your measurements will be directly affected by the jitter.
--- End quote ---
The typical output jitter (one sigma) is defined as 12ps for the ICS601 which is probably >100 times less than the time resolution of the counter. Actually I couldn't find any specification for the single shot interval resolution only the 10ps resolution for averaged (!) measurement with option 1 (TCXO). So probably even with the TCXO the single shot resolution is 500ps or more. Actually I think it could be as bad as 2ns.
I don't think a typical OCXO or TCXOs will have much better values regarding phase noise. E.g. I looked up a 100MHz VCTCXO from Abracon (ASGTX-D-100.000MHz-1 for 51,36€) and my understanding is that it has a phase noise specification of -116dBc/Hz at 10KHz for a 120MHz carrier.
So I'm not sure that an affordable TCXO or OCXO will have a much better phase noise or jitter than this multiplier solution.
Ash:

--- Quote from: 0xdeadbeef on March 02, 2018, 01:08:54 am ---
--- Quote from: Ash ---The external input is really useful I think and it is something I'd try to incorporate, but I'd be looking for a higher spec design. The problem is going to be the accuracy of your measurements will be directly affected by the jitter.
--- End quote ---
The typical output jitter (one sigma) is defined as 12ps for the ICS601 which is probably >100 times less than the time resolution of the counter. Actually I couldn't find any specification for the single shot interval resolution only the 10ps resolution for averaged (!) measurement with option 1 (TCXO). So probably even with the TCXO the single shot resolution is 500ps or more. Actually I think it could be as bad as 2ns.
I don't think a typical OCXO or TCXOs will have much better values regarding phase noise. E.g. I looked up a 100MHz VCTCXO from Abracon (ASGTX-D-100.000MHz-1 for 51,36€) and my understanding is that it has a phase noise specification of -116dBc/Hz at 10KHz for a 120MHz carrier.
So I'm not sure that an affordable TCXO or OCXO will have a much better phase noise or jitter than this multiplier solution.

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You are probably right. I wasn't really thinking through that stuff too much.  :palm: :)

I missed that you could drive the ICS670 with an external clock (I did look, but very quickly). For the price on digikey, I'd be very tempted to just give it a go given you already have a OCXO :)

Looks like a fun project. I'll certainly be following your progress if you share it!

Ash.


0xdeadbeef:
Yeah, I'm like 95% percent sure I will do this sooner or later. It's just that I guess I want to design a PCB for this and even if I should do this in the next days it will take >6 weeks or so until I get the PCBs from China. And well, you know if I'm ordering parts it usually ends with days checking what I could order additionally now that I'm ordering anyway.
So don't expect an update on this too soon ;)
Ash:

--- Quote from: 0xdeadbeef on March 02, 2018, 11:23:25 am ---Yeah, I'm like 95% percent sure I will do this sooner or later. It's just that I guess I want to design a PCB for this and even if I should do this in the next days it will take >6 weeks or so until I get the PCBs from China. And well, you know if I'm ordering parts it usually ends with days checking what I could order additionally now that I'm ordering anyway.
So don't expect an update on this too soon ;)

--- End quote ---

We are all busy and sometimes the fun stuff has to wait a bit sadly.. I have a few of those projects myself.  :(

As for ordering, I'm normally frantically trying to figure out what else I should add to the order to meet the free shipping threshold to Australia.. That often takes much longer than getting the stuff I know I need :)

Best of luck!
Ash.

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