my lab
in [Design]
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From: Phil Hobbs on 10 Oct 2009 15:58 John Larkin wrote: > On Fri, 09 Oct 2009 20:18:14 -0400, Phil Hobbs > <pcdhSpamMeSenseless(a)electrooptical.net> wrote: > >> Joerg wrote: >>> Phil Hobbs wrote: >>>> Joerg wrote: >>>>> a7yvm109gf5d1(a)netzero.com wrote: >>>>>> Well I got a HP 5316A universal counter, with the 1GHz channel and the >>>>>> OCXO. >>>>>> Very nice, I think. Although I suppose I still have the problem of not >>>>>> knowing exactly the frequency of the OCXO is, after all there are >>>>>> coarse and fine adjustments on the can... >>>>> >>>>> Well, there is WWV :-) >>>>> >>>>> >>>>>> Eh, still, I'm pretty happy with the cheap stuff you can get with a >>>>>> bit of patience. >>>>>> I think that I will build a 10V "standard" from my AD588s, in a nice >>>>>> box. >>>>>> >>>>>> So, what kind of connectivity do you guys have in yuor lab? Is >>>>>> everything GPIB, USB, or some mix? >>>>> >>>>> A mix, and that's unavoidable. Older gear that is irreplaceable >>>>> (because they simply don't make some of the good stuff anymore) >>>>> inevitably comes with those dreaded HPIB garden hose connections. The >>>>> logic analyzer and some other gear I rarely use is from the RS232 >>>>> era. Modern gear like the DSO is USB. And I will absolutely not have >>>>> HPIB garden hoses here anymore. >>>>> >>>>> So, there is a Prologix HPIB/USB adaptor, an RS232/USB adaptor plus >>>>> the traditional USB spreader octopus. I raised the equipment rack by >>>>> 1-1/2" to make all that fit underneath, plus scope probes, chargers, >>>>> international outlets, a flat vise and whatever else is needed during >>>>> lab work. Nice thing is, a laptop can now talk to all the important >>>>> boxes. >>>>> >>>> I'm so used to GPIB that I'm probably not a good example. It's a >>>> great deal nicer than RS232, and given that it's been around so long, >>>> I don't have to worry much about OSes not supporting it in >>>> detail--unlike USB. >>>> >>> GPIB is terrible. The topper happened a long time ago, after I had just >>> laid new carpet. Connector slipped off, the garden hose cable >>> ricocheted, hit my coffee mug which was half full ... *THWACK* ... flew >>> off and crashed onto new carpet. That was the end of GPIB for me. There >>> sure are better busses out there. I used to prefer RS232 but now >>> everything is USB. >>> >>> >>>> A nice Prologix GPIB-Ethernet is next on my list. >>>> >>> If you have to use equipment at clients a lot and its legacy HP stuff >>> the USB version is very practical. Plug it in, hit print on the >>> analyzer, done. But Abdul (the Prologix designer) and I had to iron out >>> a bias problem before it liked HP legacy gear. >>> >> Spilling coffee is a criticism of a bus? GPIB can do about 1 MB/s when >> externally clocked, which is better than good enough for most things I >> need to do in the lab, and if I tighten the screws I can even keep my >> coffee and my carpet. ;) >> >> Cheers >> >> Phil Hobbs > > Longterm, gigabit (and whatever comes next) Ethernet is the only > reasonable instrument bus. > > John > Sure, unless you need timing coherence between instruments. Also there's all this nice stuff around that's GPIB & RS232. I just resurrected a Keithley 410 micro-microammeter (which gives you an idea of its age--the caps inside are from 1960, and it has 8 selenium rectifiers). After replacing the power cord connector with an IEC, it powered up fine. It had almost a nanoamp of offset current when it woke up, but after 3 hours or so it's below 300 fA and still dropping. No GPIB, though. ;) Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal ElectroOptical Innovations 55 Orchard Rd Briarcliff Manor NY 10510 845-480-2058 hobbs at electrooptical dot net http://electrooptical.net
From: John Larkin on 10 Oct 2009 17:26 On Sat, 10 Oct 2009 15:58:01 -0400, Phil Hobbs <pcdhSpamMeSenseless(a)electrooptical.net> wrote: >John Larkin wrote: >> On Fri, 09 Oct 2009 20:18:14 -0400, Phil Hobbs >> <pcdhSpamMeSenseless(a)electrooptical.net> wrote: >> >>> Joerg wrote: >>>> Phil Hobbs wrote: >>>>> Joerg wrote: >>>>>> a7yvm109gf5d1(a)netzero.com wrote: >>>>>>> Well I got a HP 5316A universal counter, with the 1GHz channel and the >>>>>>> OCXO. >>>>>>> Very nice, I think. Although I suppose I still have the problem of not >>>>>>> knowing exactly the frequency of the OCXO is, after all there are >>>>>>> coarse and fine adjustments on the can... >>>>>> >>>>>> Well, there is WWV :-) >>>>>> >>>>>> >>>>>>> Eh, still, I'm pretty happy with the cheap stuff you can get with a >>>>>>> bit of patience. >>>>>>> I think that I will build a 10V "standard" from my AD588s, in a nice >>>>>>> box. >>>>>>> >>>>>>> So, what kind of connectivity do you guys have in yuor lab? Is >>>>>>> everything GPIB, USB, or some mix? >>>>>> >>>>>> A mix, and that's unavoidable. Older gear that is irreplaceable >>>>>> (because they simply don't make some of the good stuff anymore) >>>>>> inevitably comes with those dreaded HPIB garden hose connections. The >>>>>> logic analyzer and some other gear I rarely use is from the RS232 >>>>>> era. Modern gear like the DSO is USB. And I will absolutely not have >>>>>> HPIB garden hoses here anymore. >>>>>> >>>>>> So, there is a Prologix HPIB/USB adaptor, an RS232/USB adaptor plus >>>>>> the traditional USB spreader octopus. I raised the equipment rack by >>>>>> 1-1/2" to make all that fit underneath, plus scope probes, chargers, >>>>>> international outlets, a flat vise and whatever else is needed during >>>>>> lab work. Nice thing is, a laptop can now talk to all the important >>>>>> boxes. >>>>>> >>>>> I'm so used to GPIB that I'm probably not a good example. It's a >>>>> great deal nicer than RS232, and given that it's been around so long, >>>>> I don't have to worry much about OSes not supporting it in >>>>> detail--unlike USB. >>>>> >>>> GPIB is terrible. The topper happened a long time ago, after I had just >>>> laid new carpet. Connector slipped off, the garden hose cable >>>> ricocheted, hit my coffee mug which was half full ... *THWACK* ... flew >>>> off and crashed onto new carpet. That was the end of GPIB for me. There >>>> sure are better busses out there. I used to prefer RS232 but now >>>> everything is USB. >>>> >>>> >>>>> A nice Prologix GPIB-Ethernet is next on my list. >>>>> >>>> If you have to use equipment at clients a lot and its legacy HP stuff >>>> the USB version is very practical. Plug it in, hit print on the >>>> analyzer, done. But Abdul (the Prologix designer) and I had to iron out >>>> a bias problem before it liked HP legacy gear. >>>> >>> Spilling coffee is a criticism of a bus? GPIB can do about 1 MB/s when >>> externally clocked, which is better than good enough for most things I >>> need to do in the lab, and if I tighten the screws I can even keep my >>> coffee and my carpet. ;) >>> >>> Cheers >>> >>> Phil Hobbs >> >> Longterm, gigabit (and whatever comes next) Ethernet is the only >> reasonable instrument bus. >> >> John >> > >Sure, unless you need timing coherence between instruments. The IEEE-1588 protocol can sync boxes to within nanoseconds over ethernet http://en.wikipedia.org/wiki/Precision_Time_Protocol > >Also there's all this nice stuff around that's GPIB & RS232. It's also nice when an instrument has a web-page interface, and can be telnet-ed to, without any PC plugin boards or drivers. Or distance limits. > >I just resurrected a Keithley 410 micro-microammeter (which gives you an >idea of its age--the caps inside are from 1960, and it has 8 selenium >rectifiers). After replacing the power cord connector with an IEC, it >powered up fine. It had almost a nanoamp of offset current when it woke >up, but after 3 hours or so it's below 300 fA and still dropping. I got a Keithley electrometer for about $150 on ebay. All analog, of course, with a real meter on the front. The lowest ranges are 1e-14 amps and 1e14 ohms full scale. > >No GPIB, though. ;) Ditto! John
From: Joerg on 10 Oct 2009 17:40 John Larkin wrote: > On Sat, 10 Oct 2009 15:58:01 -0400, Phil Hobbs > <pcdhSpamMeSenseless(a)electrooptical.net> wrote: > >> John Larkin wrote: [...] >>> Longterm, gigabit (and whatever comes next) Ethernet is the only >>> reasonable instrument bus. >>> >>> John >>> >> Sure, unless you need timing coherence between instruments. > > The IEEE-1588 protocol can sync boxes to within nanoseconds over > ethernet > > http://en.wikipedia.org/wiki/Precision_Time_Protocol > > >> Also there's all this nice stuff around that's GPIB & RS232. > > It's also nice when an instrument has a web-page interface, and can be > telnet-ed to, without any PC plugin boards or drivers. Or distance > limits. > Hey, then you could sit there at Zeitgeist all day long and run it all via a 3G phone :-) [...] -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: John Larkin on 10 Oct 2009 17:48 On Sat, 10 Oct 2009 14:40:18 -0700, Joerg <invalid(a)invalid.invalid> wrote: >John Larkin wrote: >> On Sat, 10 Oct 2009 15:58:01 -0400, Phil Hobbs >> <pcdhSpamMeSenseless(a)electrooptical.net> wrote: >> >>> John Larkin wrote: > >[...] > >>>> Longterm, gigabit (and whatever comes next) Ethernet is the only >>>> reasonable instrument bus. >>>> >>>> John >>>> >>> Sure, unless you need timing coherence between instruments. >> >> The IEEE-1588 protocol can sync boxes to within nanoseconds over >> ethernet >> >> http://en.wikipedia.org/wiki/Precision_Time_Protocol >> >> >>> Also there's all this nice stuff around that's GPIB & RS232. >> >> It's also nice when an instrument has a web-page interface, and can be >> telnet-ed to, without any PC plugin boards or drivers. Or distance >> limits. >> > >Hey, then you could sit there at Zeitgeist all day long and run it all >via a 3G phone :-) > I guess future instruments will be Twitter compatible. John
From: Phil Hobbs on 10 Oct 2009 17:56
John Larkin wrote: > On Sat, 10 Oct 2009 15:58:01 -0400, Phil Hobbs > <pcdhSpamMeSenseless(a)electrooptical.net> wrote: > >> John Larkin wrote: >>> On Fri, 09 Oct 2009 20:18:14 -0400, Phil Hobbs >>> <pcdhSpamMeSenseless(a)electrooptical.net> wrote: >>> >>>> Joerg wrote: >>>>> Phil Hobbs wrote: >>>>>> Joerg wrote: >>>>>>> a7yvm109gf5d1(a)netzero.com wrote: >>>>>>>> Well I got a HP 5316A universal counter, with the 1GHz channel and the >>>>>>>> OCXO. >>>>>>>> Very nice, I think. Although I suppose I still have the problem of not >>>>>>>> knowing exactly the frequency of the OCXO is, after all there are >>>>>>>> coarse and fine adjustments on the can... >>>>>>> Well, there is WWV :-) >>>>>>> >>>>>>> >>>>>>>> Eh, still, I'm pretty happy with the cheap stuff you can get with a >>>>>>>> bit of patience. >>>>>>>> I think that I will build a 10V "standard" from my AD588s, in a nice >>>>>>>> box. >>>>>>>> >>>>>>>> So, what kind of connectivity do you guys have in yuor lab? Is >>>>>>>> everything GPIB, USB, or some mix? >>>>>>> A mix, and that's unavoidable. Older gear that is irreplaceable >>>>>>> (because they simply don't make some of the good stuff anymore) >>>>>>> inevitably comes with those dreaded HPIB garden hose connections. The >>>>>>> logic analyzer and some other gear I rarely use is from the RS232 >>>>>>> era. Modern gear like the DSO is USB. And I will absolutely not have >>>>>>> HPIB garden hoses here anymore. >>>>>>> >>>>>>> So, there is a Prologix HPIB/USB adaptor, an RS232/USB adaptor plus >>>>>>> the traditional USB spreader octopus. I raised the equipment rack by >>>>>>> 1-1/2" to make all that fit underneath, plus scope probes, chargers, >>>>>>> international outlets, a flat vise and whatever else is needed during >>>>>>> lab work. Nice thing is, a laptop can now talk to all the important >>>>>>> boxes. >>>>>>> >>>>>> I'm so used to GPIB that I'm probably not a good example. It's a >>>>>> great deal nicer than RS232, and given that it's been around so long, >>>>>> I don't have to worry much about OSes not supporting it in >>>>>> detail--unlike USB. >>>>>> >>>>> GPIB is terrible. The topper happened a long time ago, after I had just >>>>> laid new carpet. Connector slipped off, the garden hose cable >>>>> ricocheted, hit my coffee mug which was half full ... *THWACK* ... flew >>>>> off and crashed onto new carpet. That was the end of GPIB for me. There >>>>> sure are better busses out there. I used to prefer RS232 but now >>>>> everything is USB. >>>>> >>>>> >>>>>> A nice Prologix GPIB-Ethernet is next on my list. >>>>>> >>>>> If you have to use equipment at clients a lot and its legacy HP stuff >>>>> the USB version is very practical. Plug it in, hit print on the >>>>> analyzer, done. But Abdul (the Prologix designer) and I had to iron out >>>>> a bias problem before it liked HP legacy gear. >>>>> >>>> Spilling coffee is a criticism of a bus? GPIB can do about 1 MB/s when >>>> externally clocked, which is better than good enough for most things I >>>> need to do in the lab, and if I tighten the screws I can even keep my >>>> coffee and my carpet. ;) >>>> >>>> Cheers >>>> >>>> Phil Hobbs >>> Longterm, gigabit (and whatever comes next) Ethernet is the only >>> reasonable instrument bus. >>> >>> John >>> >> Sure, unless you need timing coherence between instruments. > > The IEEE-1588 protocol can sync boxes to within nanoseconds over > ethernet > > http://en.wikipedia.org/wiki/Precision_Time_Protocol Okay, if the data from the boxes have time stamps accurate to that level. > > >> Also there's all this nice stuff around that's GPIB & RS232. > > It's also nice when an instrument has a web-page interface, and can be > telnet-ed to, without any PC plugin boards or drivers. Or distance > limits. > >> I just resurrected a Keithley 410 micro-microammeter (which gives you an >> idea of its age--the caps inside are from 1960, and it has 8 selenium >> rectifiers). After replacing the power cord connector with an IEC, it >> powered up fine. It had almost a nanoamp of offset current when it woke >> up, but after 3 hours or so it's below 300 fA and still dropping. > > I got a Keithley electrometer for about $150 on ebay. All analog, of > course, with a real meter on the front. The lowest ranges are 1e-14 > amps and 1e14 ohms full scale. > >> No GPIB, though. ;) > > Ditto! > > John > Yeah, but mine cost $5 plus shipping. ;) 300 fA FS on the most sensitive scale for the 410. Currently the offset is running about 30 fA. Of course a lot of the resistors have drifted in 50 years--some by as much as 5-6%. I'm betting that the nice glass encapsulated ones have done better, but that'll take a bit of measuring...maybe a CMOS op amp running off a battery, with a capacitor for feedback, wired in series with the micro-microammeter. It also has less than 1 mV of burden voltage, because it's a TIA in disguise. Pretty good for toobs! Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal ElectroOptical Innovations 55 Orchard Rd Briarcliff Manor NY 10510 845-480-2058 hobbs at electrooptical dot net http://electrooptical.net |