Rectify 500MHz Small Signal
in [Design]
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From: Joerg on 30 Sep 2009 15:59 John Larkin wrote: > On Wed, 30 Sep 2009 11:30:28 -0700, Joerg <invalid(a)invalid.invalid> > wrote: > >> Nico Coesel wrote: >>> John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>> >>>> On Wed, 30 Sep 2009 16:29:03 GMT, nico(a)puntnl.niks (Nico Coesel) >>>> wrote: >>>> >>>>> John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>>>> >>>>>> On Tue, 29 Sep 2009 12:53:36 -0700, Joerg <invalid(a)invalid.invalid> >>>>>> wrote: >>>>>> >>>>>> >>>>>> There are some little USB samplers, but they're very expensive. >>>>> What amount do you consider expensive? >>>> $12K is expensive. >>> Expensive indeed. Any idea what makes these buggers so expensive? >>> >> The usual. High NRE costs, low sales volume, combined with the desire to >> make a living. >> >> You wouldn't believe what I've seen in some electro-optical gear. A >> couple of <$1 photodiodes, some MMICs or RF amps in the same price >> range, a couple BNC connectors, a (chintzy and cheap) PVC plastic >> enclosure, price tags between $500 and $1000. For that money they didn't >> even include a TVS to guard against the common ESD or "whoops, got the >> power reversed" accidents in a lab. That would have pushed the cost by >> at least 50c ... > > We, at least, use metal: > > http://www.highlandtechnology.com/DSS/J740DS.html > And I bet you have a TVS across the 12VDC line. I'd rather that folks would buy from companies like yours. But often they gravitate towards those that they know from the past or that have a "name" in their field. The gear is sometimes fancy but very pathetic. A sad episode was a TEC plus laser diode driver combo box, very expensive. Janitor plugged in his big industrial Hoover, turned it on, all the LEDs on the box lit up and then ... *PHUT* It's similar in other fields. I've lost count how many times fairly simple test jobs were done with very expensive NI gear and LabView while we did it for around a hundred bucks with a LabJack at a client. It is often impossible to convince folks that this much less expensive route can yield the same results. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: John Larkin on 30 Sep 2009 16:23 On Wed, 30 Sep 2009 12:59:03 -0700, Joerg <invalid(a)invalid.invalid> wrote: >John Larkin wrote: >> On Wed, 30 Sep 2009 11:30:28 -0700, Joerg <invalid(a)invalid.invalid> >> wrote: >> >>> Nico Coesel wrote: >>>> John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>>> >>>>> On Wed, 30 Sep 2009 16:29:03 GMT, nico(a)puntnl.niks (Nico Coesel) >>>>> wrote: >>>>> >>>>>> John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>>>>> >>>>>>> On Tue, 29 Sep 2009 12:53:36 -0700, Joerg <invalid(a)invalid.invalid> >>>>>>> wrote: >>>>>>> >>>>>>> >>>>>>> There are some little USB samplers, but they're very expensive. >>>>>> What amount do you consider expensive? >>>>> $12K is expensive. >>>> Expensive indeed. Any idea what makes these buggers so expensive? >>>> >>> The usual. High NRE costs, low sales volume, combined with the desire to >>> make a living. >>> >>> You wouldn't believe what I've seen in some electro-optical gear. A >>> couple of <$1 photodiodes, some MMICs or RF amps in the same price >>> range, a couple BNC connectors, a (chintzy and cheap) PVC plastic >>> enclosure, price tags between $500 and $1000. For that money they didn't >>> even include a TVS to guard against the common ESD or "whoops, got the >>> power reversed" accidents in a lab. That would have pushed the cost by >>> at least 50c ... >> >> We, at least, use metal: >> >> http://www.highlandtechnology.com/DSS/J740DS.html >> > >And I bet you have a TVS across the 12VDC line. After the radial-lead polyfuse. The surface-mount ones suck. I'd rather that folks >would buy from companies like yours. But often they gravitate towards >those that they know from the past or that have a "name" in their field. >The gear is sometimes fancy but very pathetic. A sad episode was a TEC >plus laser diode driver combo box, very expensive. Janitor plugged in >his big industrial Hoover, turned it on, all the LEDs on the box lit up >and then ... *PHUT* > >It's similar in other fields. I've lost count how many times fairly >simple test jobs were done with very expensive NI gear and LabView while >we did it for around a hundred bucks with a LabJack at a client. It is >often impossible to convince folks that this much less expensive route >can yield the same results. Luckily few of my cusomers want to mess with LabView. John
From: Joerg on 30 Sep 2009 17:26 John Larkin wrote: > On Wed, 30 Sep 2009 12:59:03 -0700, Joerg <invalid(a)invalid.invalid> > wrote: > >> John Larkin wrote: >>> On Wed, 30 Sep 2009 11:30:28 -0700, Joerg <invalid(a)invalid.invalid> >>> wrote: >>> >>>> Nico Coesel wrote: >>>>> John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>>>> >>>>>> On Wed, 30 Sep 2009 16:29:03 GMT, nico(a)puntnl.niks (Nico Coesel) >>>>>> wrote: >>>>>> >>>>>>> John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>>>>>> >>>>>>>> On Tue, 29 Sep 2009 12:53:36 -0700, Joerg <invalid(a)invalid.invalid> >>>>>>>> wrote: >>>>>>>> >>>>>>>> >>>>>>>> There are some little USB samplers, but they're very expensive. >>>>>>> What amount do you consider expensive? >>>>>> $12K is expensive. >>>>> Expensive indeed. Any idea what makes these buggers so expensive? >>>>> >>>> The usual. High NRE costs, low sales volume, combined with the desire to >>>> make a living. >>>> >>>> You wouldn't believe what I've seen in some electro-optical gear. A >>>> couple of <$1 photodiodes, some MMICs or RF amps in the same price >>>> range, a couple BNC connectors, a (chintzy and cheap) PVC plastic >>>> enclosure, price tags between $500 and $1000. For that money they didn't >>>> even include a TVS to guard against the common ESD or "whoops, got the >>>> power reversed" accidents in a lab. That would have pushed the cost by >>>> at least 50c ... >>> We, at least, use metal: >>> >>> http://www.highlandtechnology.com/DSS/J740DS.html >>> >> And I bet you have a TVS across the 12VDC line. > > After the radial-lead polyfuse. The surface-mount ones suck. > Good man :-) The usual scenario would be that either the power supply limits or a PVC stench develops. > > I'd rather that folks >> would buy from companies like yours. But often they gravitate towards >> those that they know from the past or that have a "name" in their field. >> The gear is sometimes fancy but very pathetic. A sad episode was a TEC >> plus laser diode driver combo box, very expensive. Janitor plugged in >> his big industrial Hoover, turned it on, all the LEDs on the box lit up >> and then ... *PHUT* >> >> It's similar in other fields. I've lost count how many times fairly >> simple test jobs were done with very expensive NI gear and LabView while >> we did it for around a hundred bucks with a LabJack at a client. It is >> often impossible to convince folks that this much less expensive route >> can yield the same results. > > Luckily few of my cusomers want to mess with LabView. > What are they using? SCADA software? -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: John Larkin on 30 Sep 2009 18:24 On Wed, 30 Sep 2009 14:26:46 -0700, Joerg <invalid(a)invalid.invalid> wrote: >John Larkin wrote: >> On Wed, 30 Sep 2009 12:59:03 -0700, Joerg <invalid(a)invalid.invalid> >> wrote: >> >>> John Larkin wrote: >>>> On Wed, 30 Sep 2009 11:30:28 -0700, Joerg <invalid(a)invalid.invalid> >>>> wrote: >>>> >>>>> Nico Coesel wrote: >>>>>> John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>>>>> >>>>>>> On Wed, 30 Sep 2009 16:29:03 GMT, nico(a)puntnl.niks (Nico Coesel) >>>>>>> wrote: >>>>>>> >>>>>>>> John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>>>>>>> >>>>>>>>> On Tue, 29 Sep 2009 12:53:36 -0700, Joerg <invalid(a)invalid.invalid> >>>>>>>>> wrote: >>>>>>>>> >>>>>>>>> >>>>>>>>> There are some little USB samplers, but they're very expensive. >>>>>>>> What amount do you consider expensive? >>>>>>> $12K is expensive. >>>>>> Expensive indeed. Any idea what makes these buggers so expensive? >>>>>> >>>>> The usual. High NRE costs, low sales volume, combined with the desire to >>>>> make a living. >>>>> >>>>> You wouldn't believe what I've seen in some electro-optical gear. A >>>>> couple of <$1 photodiodes, some MMICs or RF amps in the same price >>>>> range, a couple BNC connectors, a (chintzy and cheap) PVC plastic >>>>> enclosure, price tags between $500 and $1000. For that money they didn't >>>>> even include a TVS to guard against the common ESD or "whoops, got the >>>>> power reversed" accidents in a lab. That would have pushed the cost by >>>>> at least 50c ... >>>> We, at least, use metal: >>>> >>>> http://www.highlandtechnology.com/DSS/J740DS.html >>>> >>> And I bet you have a TVS across the 12VDC line. >> >> After the radial-lead polyfuse. The surface-mount ones suck. >> > >Good man :-) > >The usual scenario would be that either the power supply limits or a PVC >stench develops. > >> >> I'd rather that folks >>> would buy from companies like yours. But often they gravitate towards >>> those that they know from the past or that have a "name" in their field. >>> The gear is sometimes fancy but very pathetic. A sad episode was a TEC >>> plus laser diode driver combo box, very expensive. Janitor plugged in >>> his big industrial Hoover, turned it on, all the LEDs on the box lit up >>> and then ... *PHUT* >>> >>> It's similar in other fields. I've lost count how many times fairly >>> simple test jobs were done with very expensive NI gear and LabView while >>> we did it for around a hundred bucks with a LabJack at a client. It is >>> often impossible to convince folks that this much less expensive route >>> can yield the same results. >> >> Luckily few of my cusomers want to mess with LabView. >> > >What are they using? SCADA software? The jet engine and FADEC test folks usually write their own system software, using RT Linux or some such. Test runs are often script driven, may involve thousands of channels of stimulation and acquisition, and may run for days. They have to simulate 1553 busses, pitot tubes, thermocouples, tach pickups, vibration things, pressure sensors, LVDTs, all sorts of nonsense. And then faults on all of the above. Hmmm, maybe I should do an LVDT simulator. Could be fun. John
From: Joerg on 30 Sep 2009 18:56
John Larkin wrote: > On Wed, 30 Sep 2009 14:26:46 -0700, Joerg <invalid(a)invalid.invalid> > wrote: > >> John Larkin wrote: >>> On Wed, 30 Sep 2009 12:59:03 -0700, Joerg <invalid(a)invalid.invalid> >>> wrote: >>> >>>> John Larkin wrote: >>>>> On Wed, 30 Sep 2009 11:30:28 -0700, Joerg <invalid(a)invalid.invalid> >>>>> wrote: >>>>> >>>>>> Nico Coesel wrote: >>>>>>> John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>>>>>> >>>>>>>> On Wed, 30 Sep 2009 16:29:03 GMT, nico(a)puntnl.niks (Nico Coesel) >>>>>>>> wrote: >>>>>>>> >>>>>>>>> John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >>>>>>>>> >>>>>>>>>> On Tue, 29 Sep 2009 12:53:36 -0700, Joerg <invalid(a)invalid.invalid> >>>>>>>>>> wrote: >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> There are some little USB samplers, but they're very expensive. >>>>>>>>> What amount do you consider expensive? >>>>>>>> $12K is expensive. >>>>>>> Expensive indeed. Any idea what makes these buggers so expensive? >>>>>>> >>>>>> The usual. High NRE costs, low sales volume, combined with the desire to >>>>>> make a living. >>>>>> >>>>>> You wouldn't believe what I've seen in some electro-optical gear. A >>>>>> couple of <$1 photodiodes, some MMICs or RF amps in the same price >>>>>> range, a couple BNC connectors, a (chintzy and cheap) PVC plastic >>>>>> enclosure, price tags between $500 and $1000. For that money they didn't >>>>>> even include a TVS to guard against the common ESD or "whoops, got the >>>>>> power reversed" accidents in a lab. That would have pushed the cost by >>>>>> at least 50c ... >>>>> We, at least, use metal: >>>>> >>>>> http://www.highlandtechnology.com/DSS/J740DS.html >>>>> >>>> And I bet you have a TVS across the 12VDC line. >>> After the radial-lead polyfuse. The surface-mount ones suck. >>> >> Good man :-) >> >> The usual scenario would be that either the power supply limits or a PVC >> stench develops. >> >>> I'd rather that folks >>>> would buy from companies like yours. But often they gravitate towards >>>> those that they know from the past or that have a "name" in their field. >>>> The gear is sometimes fancy but very pathetic. A sad episode was a TEC >>>> plus laser diode driver combo box, very expensive. Janitor plugged in >>>> his big industrial Hoover, turned it on, all the LEDs on the box lit up >>>> and then ... *PHUT* >>>> >>>> It's similar in other fields. I've lost count how many times fairly >>>> simple test jobs were done with very expensive NI gear and LabView while >>>> we did it for around a hundred bucks with a LabJack at a client. It is >>>> often impossible to convince folks that this much less expensive route >>>> can yield the same results. >>> Luckily few of my cusomers want to mess with LabView. >>> >> What are they using? SCADA software? > > The jet engine and FADEC test folks usually write their own system > software, using RT Linux or some such. Test runs are often script > driven, may involve thousands of channels of stimulation and > acquisition, and may run for days. They have to simulate 1553 busses, > pitot tubes, thermocouples, tach pickups, vibration things, pressure > sensors, LVDTs, all sorts of nonsense. And then faults on all of the > above. > Wow, ok, that's a different caliber. One of my newer clients in in that biz as well. Luckily I'll only have to connect to their custom test rig, the programming will be done by others. > Hmmm, maybe I should do an LVDT simulator. Could be fun. > I just got DAQFactory back to work. Was like pulling teeth. Almost like an old engine that hadn't been started up in years. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM. |