Re: [Emc-users] PCB adapters for oscilloscope probes
On Tue, Mar 17, 2015 at 5:21 PM, Philipp Burch p...@hb9etc.ch wrote: Hi everyone, please excuse this question very unrelated to LinuxCNC, but I know that here are quite some people around who are familiar with scopes and high-frequency measurements. Some who like Tek and some who don't ;) Anyway, I've got a project where I need to measure signals with frequencies in the range 10Mhz .. 100Mhz without loading the driver itself too much (the goal is to figure out how a current control loop behaves at these frequencies, so I should not add much more phase lag just by attaching the probe). Tektronix probes of type P6158 ( http://www.tek.com/sites/tek.com/files/media/media/resources/60W_12026_2_0.pdf ) are available, so this is ok. What we haven't a large amount of, however, are those PCB adapters (the ones with the four ground pins, where you can stick the probe vertically into). Something like this: http://hb9etc.ch/images/tek_probe_adapter_131-4244-00.png Now the question: Does anyone here have an idea how or where to get some spares of those adapters? The part# 131-4244-00 does not seem to exist anymore. In the probe datasheet, there is 131-5031-00 listed for those adapters, but market results aren't much better for those. What I found so far is a product on Amazon: http://www.amazon.com/Tektronix-131-5031-00-Tip-Probe/dp/B00DJS7BMU This could probably be the right thing, but $184 for 25 of those thingies is also quite a number. Might be worth it, but still, if anyone has a better idea/source/offer/whatever, please tell me. Thanks! Cheers, Philipp Philpp, That was more than likely a Tek made part, most likely a derivative of their Peltola connectors. We used to have a bunch of those here at work, but someone did a housecleaning, and I'm afraid they went into the dumpster. At any rate, Tekronix doesn't make them any more, and probably about the only place you will find them is on Ebay. That Ebay seller is obviously smoking some new kind of crack. That's a completely ridiculous price for 25. Tek used to package those in quantities of 100. Mark -- Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] PCB adapters for oscilloscope probes
Hi Mark! On 18.03.2015 10:16, Mark Wendt wrote: On Tue, Mar 17, 2015 at 5:21 PM, Philipp Burch p...@hb9etc.ch wrote: ... Philpp, That was more than likely a Tek made part, most likely a derivative of their Peltola connectors. We used to have a bunch of those here at work, but someone did a housecleaning, and I'm afraid they went into the dumpster. At any rate, Tekronix doesn't make them any more, and probably about the only place you will find them is on Ebay. That Ebay seller is obviously smoking some new kind of crack. That's a completely ridiculous price for 25. Tek used to package those in quantities of 100. Mark I think they replaced the part by the newer 131-5031-00, which actually exists on the Tek page (at least somehow) and is listed in the probe datasheet. Anyway, I'll find some way to do it, with so many good suggestions. The adapters have exactly been designed into the PCB, or at least almost, I will need to cut away two of the legs of the adapters to fit them into the tiny space I have. So there is a PTH right inside the signal trace for the tip and four/two PTH around it for the ground connection. Cheers, Philipp signature.asc Description: OpenPGP digital signature -- Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] OT: Allen Bradley PowerFlex 40 question
On 12.03.15 14:46, richsh...@comcast.net wrote: Just a reminder, using this kind of equipment in the US does require a license from the FCC! It is a radio transmitter and as such it does require compliance with the rules. Had a furniture factory that used RF heating for setting glue, worked great, BTW, but there it was, an FCC station license right on the side of the power supply. Back in the days of analogue telecommunications, when telephone trunks were FDM on coax, there was a small furniture factory a few blocks from our design lab. On days when he arced his up, the needles on our level meters would jump and stay up for the duration of their heating cycle. We had to make our measurements in between workpieces in their factory. The digital revolution has a lot going for it. Erik -- The world is spending half a trillion dollars on fossil fuel subsidies every year, according to a new report. The Overseas Development Institute (ODI) says rich countries are spending seven times more supporting coal, oil and gas than they are on helping poorer nations fight climate change. - http://www.bbc.co.uk/news/science-environment-24833153 -- Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] VFD causing limits to trip. Huh?
If one is trying to minimize radiated interference from a signal source, then grounding the shield at the source end makes sense. My suggestion of grounding the shield at the consumer of the signals was based on reducing the likelihood of a hostile external noise source confusing the consumer. Steve Stallings -Original Message- From: Przemek Klosowski [mailto:przemek.klosow...@gmail.com] Sent: Wednesday, March 18, 2015 11:12 AM To: Enhanced Machine Controller (EMC) Subject: Re: [Emc-users] VFD causing limits to trip. Huh? On Mon, Mar 16, 2015 at 11:34 AM, Peter Blodow p.blo...@dreki.de wrote: Steve, this is a good description of noise reduction by shielding. To make it more exact, the shield should be grounded at the end where the lower impedance is, mostly the signal source. This is opposite to what Steve said, which was to ground near the signals are consumed, which makes more sense to me because shield potentials, if any, have smaller chance of leaking through to the signal wires. From the impedance point of view, I would also worry more about interference near high-impedance nodes rather than low-impedance nodes, just because smal currents result in larger voltages there. Can you summarize the rationale for your recommendation in the language of electromagnetics? -- Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] VFD causing limits to trip. Huh?
I also agree about this. Nicklas Karlsson On Wed, 18 Mar 2015 12:43:16 -0500 Steve Stallings steve...@newsguy.com wrote: If one is trying to minimize radiated interference from a signal source, then grounding the shield at the source end makes sense. My suggestion of grounding the shield at the consumer of the signals was based on reducing the likelihood of a hostile external noise source confusing the consumer. Steve Stallings -Original Message- From: Przemek Klosowski [mailto:przemek.klosow...@gmail.com] Sent: Wednesday, March 18, 2015 11:12 AM To: Enhanced Machine Controller (EMC) Subject: Re: [Emc-users] VFD causing limits to trip. Huh? On Mon, Mar 16, 2015 at 11:34 AM, Peter Blodow p.blo...@dreki.de wrote: Steve, this is a good description of noise reduction by shielding. To make it more exact, the shield should be grounded at the end where the lower impedance is, mostly the signal source. This is opposite to what Steve said, which was to ground near the signals are consumed, which makes more sense to me because shield potentials, if any, have smaller chance of leaking through to the signal wires. From the impedance point of view, I would also worry more about interference near high-impedance nodes rather than low-impedance nodes, just because smal currents result in larger voltages there. Can you summarize the rationale for your recommendation in the language of electromagnetics? -- Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] VFD causing limits to trip. Huh?
On Mon, Mar 16, 2015 at 11:34 AM, Peter Blodow p.blo...@dreki.de wrote: Steve, this is a good description of noise reduction by shielding. To make it more exact, the shield should be grounded at the end where the lower impedance is, mostly the signal source. This is opposite to what Steve said, which was to ground near the signals are consumed, which makes more sense to me because shield potentials, if any, have smaller chance of leaking through to the signal wires. From the impedance point of view, I would also worry more about interference near high-impedance nodes rather than low-impedance nodes, just because smal currents result in larger voltages there. Can you summarize the rationale for your recommendation in the language of electromagnetics? -- Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] PCB adapters for oscilloscope probes
At the very very small level Cascade has some stuff https://www.cmicro.com/products A design for PCBs from another maker http://www.ggb.com/40a.html their 40A looks like a good idea a FET probe (many makers) and I like Peters idea of build it in or I think on a probing assembly you put on top or under. The sites I point to above are probe tips to add to a test jig of some sort. Some jig images at http://www.hsprobe.com/RFProbe.html Be very careful your probing does not affect the circuit, It is very easy to accidently add a micro stripline to your circuit making a resonant element (causing ringing or worse). This comes from my experience as part of a team working on a video switcher. Dave Caroline I just did a RF probing then a rf pcb probing google search On 18/03/2015, Philipp Burch p...@hb9etc.ch wrote: Hello everyone! Thanks for all the great responses. I looks like it will boil down to creating something own. @Florian: Excellent idea with the DIL socket! I already thought about putting together something own, but those sockets for the tip connection didn't come to my mind. Other probes suitable for this application aren't available, so I'm stuck with this 3.5mm stuff, I guess. Also the SMB/SMC connector with the spring-loaded 3.6mm diameter is a good idea! @andy, Peter: Building the probe using a series resistor and an SMA/MCX connector on my own also came to my mind, but just a little too late, since the PCBs are being manufactured already. But it will definitely be an option for next time. Since you are suggesting it, I believe it will actually work ;) @Bertho: A little PCB for the ground connection seems to be a good idea, thanks for that! @Roger: The resistive part of the load isn't that much of a problem, since it does not interfere with the controller operation. I'll have to take it into account, but that's much less of an issue than a capacitance of a few pF. The signals are also quite low-impedance (at least when it comes to DC), so that's ok. Cheers, Philipp On 17.03.2015 23:20, Florian Rist wrote: Hi Philipp Now the question: Does anyone here have an idea how or where to get some spares of those adapters? Do you have other probes available as well? It's much easier to find these adapters for 2.5 mm probes. http://www.digikey.com/product-detail/en/PK106-4/PK106-4-ND/3587113 http://www.keysight.com/en/pd-2422998-pn-N4864A/25-mm-probe-tip-to-pcb-adaptor-vertical?cc=ATlc=ger Using your probes, don't you think you'd bee good just using any suitable receptacle for the tip and the ground spring contact on the probe to connect to a ground plane? You could extract a single pin from precision DIL socket for the probe tip. If you need 'full' pcb adapter for the 3.5mm probes and since this is the LinxCNC mailing list, you could get a few carrier DIL socket for the center pin and mill the outer sleeve from a piece of brass. https://www.buerklin.com/de/katalog/Carrier-IC-Fassungen-Typ-MPE-GARRY-MC-Metal-Carrier-DIL-B091000.html (I'm not 100% sure if a standard probe tip fits in..) See you Flo -- Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] PCB adapters for oscilloscope probes
Hi Dave! On 18.03.2015 08:19, Dave Caroline wrote: At the very very small level Cascade has some stuff https://www.cmicro.com/products A design for PCBs from another maker http://www.ggb.com/40a.html their 40A looks like a good idea a FET probe (many makers) and I like Peters idea of build it in or I think on a probing assembly you put on top or under. The sites I point to above are probe tips to add to a test jig of some sort. Some jig images at http://www.hsprobe.com/RFProbe.html Be very careful your probing does not affect the circuit, It is very easy to accidently add a micro stripline to your circuit making a resonant element (causing ringing or worse). This comes from my experience as part of a team working on a video switcher. Dave Caroline I just did a RF probing then a rf pcb probing google search Thanks! Those adapters probably are not that ideal for me, however (and with bandwidths in the tens of GHz also quite a bit overkill), as I would like to have something that I can solder onto the PCB to have it staying there. Ideally, I could throw the PCB into a drawer after use and some time later put it back on the table and make the same (or at least close) measurements as in the first time. This would be quite difficult if there is a complicated setup necessary with probe holders and manual adjusting, etc. Building a whole test jig is, again, a bit too much for now, but maybe an option of last resort. In case nothing else works. Regards, Philipp signature.asc Description: OpenPGP digital signature -- Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] PCB adapters for oscilloscope probes
Hello everyone! Thanks for all the great responses. I looks like it will boil down to creating something own. @Florian: Excellent idea with the DIL socket! I already thought about putting together something own, but those sockets for the tip connection didn't come to my mind. Other probes suitable for this application aren't available, so I'm stuck with this 3.5mm stuff, I guess. Also the SMB/SMC connector with the spring-loaded 3.6mm diameter is a good idea! @andy, Peter: Building the probe using a series resistor and an SMA/MCX connector on my own also came to my mind, but just a little too late, since the PCBs are being manufactured already. But it will definitely be an option for next time. Since you are suggesting it, I believe it will actually work ;) @Bertho: A little PCB for the ground connection seems to be a good idea, thanks for that! @Roger: The resistive part of the load isn't that much of a problem, since it does not interfere with the controller operation. I'll have to take it into account, but that's much less of an issue than a capacitance of a few pF. The signals are also quite low-impedance (at least when it comes to DC), so that's ok. Cheers, Philipp On 17.03.2015 23:20, Florian Rist wrote: Hi Philipp Now the question: Does anyone here have an idea how or where to get some spares of those adapters? Do you have other probes available as well? It's much easier to find these adapters for 2.5 mm probes. http://www.digikey.com/product-detail/en/PK106-4/PK106-4-ND/3587113 http://www.keysight.com/en/pd-2422998-pn-N4864A/25-mm-probe-tip-to-pcb-adaptor-vertical?cc=ATlc=ger Using your probes, don't you think you'd bee good just using any suitable receptacle for the tip and the ground spring contact on the probe to connect to a ground plane? You could extract a single pin from precision DIL socket for the probe tip. If you need 'full' pcb adapter for the 3.5mm probes and since this is the LinxCNC mailing list, you could get a few carrier DIL socket for the center pin and mill the outer sleeve from a piece of brass. https://www.buerklin.com/de/katalog/Carrier-IC-Fassungen-Typ-MPE-GARRY-MC-Metal-Carrier-DIL-B091000.html (I'm not 100% sure if a standard probe tip fits in..) See you Flo -- Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users signature.asc Description: OpenPGP digital signature -- Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
