low MHz connector design consultant
in [Design]
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From: mpm on 1 May 2010 03:34 On Apr 30, 10:58 pm, "k...(a)att.bizzzzzzzzzzzz" <k...(a)att.bizzzzzzzzzzzz> wrote: > On Fri, 30 Apr 2010 18:39:21 -0700 (PDT), mpm <mpmill...(a)aol.com> wrote: > >On Apr 30, 4:31 pm, Wimpie <wimabc...(a)tetech.nl> wrote: > >> On 30 abr, 13:54, "mook johnson" <m...(a)mook.net> wrote: > > >> > "John Larkin" <jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote in message > > >> >news:ql9kt5tg7s7e5q7pb460gcdig4r00jjmrj(a)4ax.com... > > >> > > On Thu, 29 Apr 2010 18:30:41 -0500, "mook johnson" <m...(a)mook.net> > >> > > wrote: > > >> > >>Gents, > > >> > >>I looking for a consultant that can assist in the design of a custom > >> > >>military style connector with controlled characteristic impedance and > >> > >>insertion loss between two terminals in the 1MHz - 20MHz frequency range. > > >> > >>This connector is special because is the application so an off the shelf > >> > >>component will not work. > > >> > >>Any leads where I can start looking for such a consultant? > > >> > >>thanks > > >> > > There are so many military connectors, including ones for wild > >> > > environments, hermetic, etc, some standard part might work. > > >> > > 20 MHz isn't very demanding. Most any mil connector will be "matched" > >> > > to any impedance at 20 MHz. Wavelength is 15 meters! > > >> > > John > > >> > The connector I need goes into environments that far exceed military > >> > applications but the physical concept is similar. We have an in-house > >> > connector company that makes these connectors for us but they have never had > >> > to deal with never greater than >200KHz signals before. We tried using our > >> > regular connectors for this application and the impedance mismatch and > >> > insertion loss were extreme at 5 - 20MHz. The Zo mismatched by 50% and was > >> > not stable above 1MHz and had several resonant modes. Insertion loss > >> > something on the order is 6dB/connector and we'll have a couple dozen in > >> > series on this line. The number of series connection is the is the rub and > >> > it is unavoidable, non negotiable. > > >> > There are some commercial plastic connectors that tested very well (just to > >> > validate our test setup) with good impedance match/stability (+/- 5%) and > >> > low insertion loss (.1dB/connector) but they won't take the environment. > > >> > I'm looking for a consultant that can provide either of the following > > >> > 1) model a connector that is already designed but not made (basically review > >> > the in-house company proposed design) and simulate the high frequency > >> > response of the design. > > >> > 2) Give direction for the connector design based on constraints of material > >> > choices, physical size and geometry to meet the desired electrical signal > >> > characteristics while withstanding the environmental conditions. > > >> > The cut and try approach based on simple equations has a long cycle time. > >> > I'm looking to improve my chances of getting it right the first time.. > > >> Hello Mook, > > >> When you have already a company that knows mechanical design and > >> reliability issues, you only need the EM-field guy. When you can > >> keep the mechanical guys and the EM-field guy in one room, this should > >> converge to a solution fast. > > >> One familiar with the concept of characteristic impedance, complex > >> propagation constant (contains both complex epsilon and permeability) > >> and know how to measure the material constants can do the job. > > >> What about: required Return Loss, characteristic impedance, Insertion > >> loss, propagation delay, size, cross section, (coaxial, square, > >> symmetrical, etc), peak and average power, etc? > > >> Kind regards, > > >> Wim > >> PA3DJSwww.tetech.nl > >> when you delete abc first, PM will reach me- Hide quoted text - > > >> - Show quoted text - > > >I have a question for you: > > >Do you believe that the characteristic impedance is dependent on the > >length of the coax? > >(For the ratio of transverse electric field to transverse magnetic > >field launched on a transmission line of infinite length.) > > "infinite length" <> "independent of length"- Hide quoted text - > > - Show quoted text - Not sure I understand your cryptic post. That is how characteristic impedance is classically defined, and I'm asking him if he believes that characteristic impedance is dependent on length?
From: Wimpie on 1 May 2010 07:08 On 1 mayo, 03:39, mpm <mpmill...(a)aol.com> wrote: > On Apr 30, 4:31 pm, Wimpie <wimabc...(a)tetech.nl> wrote: > > > > > On 30 abr, 13:54, "mook johnson" <m...(a)mook.net> wrote: > > > > "John Larkin" <jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote in message > > > >news:ql9kt5tg7s7e5q7pb460gcdig4r00jjmrj(a)4ax.com... > > > > > On Thu, 29 Apr 2010 18:30:41 -0500, "mook johnson" <m...(a)mook.net> > > > > wrote: > > > > >>Gents, > > > > >>I looking for a consultant that can assist in the design of a custom > > > >>military style connector with controlled characteristic impedance and > > > >>insertion loss between two terminals in the 1MHz - 20MHz frequency range. > > > > >>This connector is special because is the application so an off the shelf > > > >>component will not work. > > > > >>Any leads where I can start looking for such a consultant? > > > > >>thanks > > > > > There are so many military connectors, including ones for wild > > > > environments, hermetic, etc, some standard part might work. > > > > > 20 MHz isn't very demanding. Most any mil connector will be "matched" > > > > to any impedance at 20 MHz. Wavelength is 15 meters! > > > > > John > > > > The connector I need goes into environments that far exceed military > > > applications but the physical concept is similar. We have an in-house > > > connector company that makes these connectors for us but they have never had > > > to deal with never greater than >200KHz signals before. We tried using our > > > regular connectors for this application and the impedance mismatch and > > > insertion loss were extreme at 5 - 20MHz. The Zo mismatched by 50% and was > > > not stable above 1MHz and had several resonant modes. Insertion loss > > > something on the order is 6dB/connector and we'll have a couple dozen in > > > series on this line. The number of series connection is the is the rub and > > > it is unavoidable, non negotiable. > > > > There are some commercial plastic connectors that tested very well (just to > > > validate our test setup) with good impedance match/stability (+/- 5%) and > > > low insertion loss (.1dB/connector) but they won't take the environment. > > > > I'm looking for a consultant that can provide either of the following > > > > 1) model a connector that is already designed but not made (basically review > > > the in-house company proposed design) and simulate the high frequency > > > response of the design. > > > > 2) Give direction for the connector design based on constraints of material > > > choices, physical size and geometry to meet the desired electrical signal > > > characteristics while withstanding the environmental conditions. > > > > The cut and try approach based on simple equations has a long cycle time. > > > I'm looking to improve my chances of getting it right the first time. > > > Hello Mook, > > > When you have already a company that knows mechanical design and > > reliability issues, you only need the EM-field guy. When you can > > keep the mechanical guys and the EM-field guy in one room, this should > > converge to a solution fast. > > > One familiar with the concept of characteristic impedance, complex > > propagation constant (contains both complex epsilon and permeability) > > and know how to measure the material constants can do the job. > > > What about: required Return Loss, characteristic impedance, Insertion > > loss, propagation delay, size, cross section, (coaxial, square, > > symmetrical, etc), peak and average power, etc? > > > Kind regards, > > > Wim > > PA3DJSwww.tetech.nl > > when you delete abc first, PM will reach me- Hide quoted text - > > > - Show quoted text - > > I have a question for you: > > Do you believe that the characteristic impedance is dependent on the > length of the coax? No, but why this question? > (For the ratio of transverse electric field to transverse magnetic > field launched on a transmission line of infinite length.) > > -mpm Best regards, Wim PA3DJS www.tetech.nl remove abc first in case of PM
From: mook johnson on 1 May 2010 07:41 "tm" <noone(a)msc.com> wrote in message news:hrejfa$jc3$1(a)speranza.aioe.org... > > "tm" <noone(a)msc.com> wrote in message > news:hrejb7$j6e$1(a)speranza.aioe.org... >> >> "mook johnson" <mook(a)mook.net> wrote in message >> news:CEoCn.150671$gF5.132244(a)newsfe13.iad... >>> Gents, >>> >>> I looking for a consultant that can assist in the design of a custom >>> military style connector with controlled characteristic impedance and >>> insertion loss between two terminals in the 1MHz - 20MHz frequency >>> range. >>> >>> This connector is special because is the application so an off the shelf >>> component will not work. >>> >>> Any leads where I can start looking for such a consultant? >>> >>> thanks >>> >>> >>> >> Go you have a valid email address? >> >> Tom >> > That should be "do you have an email address?" The one above bounces. intentionally scrambled to slow down the spambots. "yahoo inbox is jmook60"
From: krw on 1 May 2010 10:17 On Sat, 1 May 2010 00:34:48 -0700 (PDT), mpm <mpmillard(a)aol.com> wrote: >On Apr 30, 10:58�pm, "k...(a)att.bizzzzzzzzzzzz" ><k...(a)att.bizzzzzzzzzzzz> wrote: >> On Fri, 30 Apr 2010 18:39:21 -0700 (PDT), mpm <mpmill...(a)aol.com> wrote: >> >On Apr 30, 4:31�pm, Wimpie <wimabc...(a)tetech.nl> wrote: >> >> On 30 abr, 13:54, "mook johnson" <m...(a)mook.net> wrote: >> >> >> > "John Larkin" <jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote in message >> >> >> >news:ql9kt5tg7s7e5q7pb460gcdig4r00jjmrj(a)4ax.com... >> >> >> > > On Thu, 29 Apr 2010 18:30:41 -0500, "mook johnson" <m...(a)mook.net> >> >> > > wrote: >> >> >> > >>Gents, >> >> >> > >>I looking for a consultant that can assist in the design of a custom >> >> > >>military style connector with controlled characteristic impedance and >> >> > >>insertion loss between two terminals in the 1MHz - 20MHz frequency range. >> >> >> > >>This connector is special because is the application so an off the shelf >> >> > >>component will not work. >> >> >> > >>Any leads where I can start looking for such a consultant? >> >> >> > >>thanks >> >> >> > > There are so many military connectors, including ones for wild >> >> > > environments, hermetic, etc, some standard part might work. >> >> >> > > 20 MHz isn't very demanding. Most any mil connector will be "matched" >> >> > > to any impedance at 20 MHz. Wavelength is 15 meters! >> >> >> > > John >> >> >> > The connector I need goes into environments that far exceed military >> >> > applications but the physical concept is similar. �We have an in-house >> >> > connector company that makes these connectors for us but they have never had >> >> > to deal with never greater than >200KHz signals before. �We tried using our >> >> > regular connectors for this application and the impedance mismatch and >> >> > insertion loss were extreme at 5 - 20MHz. �The Zo mismatched by 50% and was >> >> > not stable above 1MHz and had several resonant modes. Insertion loss >> >> > something on the order is 6dB/connector and we'll have a couple dozen in >> >> > series on this line. �The number of series connection is the is the rub and >> >> > it is unavoidable, non negotiable. >> >> >> > There are some commercial plastic connectors that tested very well (just to >> >> > validate our test setup) with good impedance match/stability (+/- 5%) and >> >> > low insertion loss (.1dB/connector) but they won't take the environment. >> >> >> > I'm looking for a consultant that can provide either of the following >> >> >> > 1) model a connector that is already designed but not made (basically review >> >> > the in-house company proposed design) and simulate the high frequency >> >> > response of the design. >> >> >> > 2) Give direction for the connector design based on constraints of material >> >> > choices, physical size and geometry to meet the desired electrical signal >> >> > characteristics while withstanding the environmental conditions. >> >> >> > The cut and try approach based on simple equations has a long cycle time. >> >> > I'm looking to improve my chances of getting it right the first time. >> >> >> Hello Mook, >> >> >> When you have already a company that knows mechanical design and >> >> reliability issues, you only need the EM-field guy. � When you can >> >> keep the mechanical guys and the EM-field guy in one room, this should >> >> converge to a solution fast. >> >> >> One familiar with the concept of characteristic impedance, complex >> >> propagation constant (contains both complex epsilon and permeability) >> >> and know how to measure the material constants can do the job. >> >> >> What about: required Return Loss, characteristic impedance, Insertion >> >> loss, propagation delay, size, �cross section, (coaxial, square, >> >> symmetrical, etc), peak and average power, etc? >> >> >> Kind regards, >> >> >> Wim >> >> PA3DJSwww.tetech.nl >> >> when you delete abc first, PM will reach me- Hide quoted text - >> >> >> - Show quoted text - >> >> >I have a question for you: >> >> >Do you believe that the characteristic impedance is dependent on the >> >length of the coax? >> >(For the ratio of transverse electric field to transverse magnetic >> >field launched on a transmission line of infinite length.) >> >> "infinite length" <> "independent of length"- Hide quoted text - >> >> - Show quoted text - > >Not sure I understand your cryptic post. > >That is how characteristic impedance is classically defined, and I'm >asking him if he believes that characteristic impedance is dependent >on length? But you talk about dependency on length and "infinite" length in the same paragraph. You can't have both variable length (which would include short) and a dependency on being "infinite".
From: mpm on 1 May 2010 15:00
On May 1, 9:17 am, "k...(a)att.bizzzzzzzzzzzz" <k...(a)att.bizzzzzzzzzzzz> wrote: > On Sat, 1 May 2010 00:34:48 -0700 (PDT), mpm <mpmill...(a)aol.com> wrote: > >On Apr 30, 10:58 pm, "k...(a)att.bizzzzzzzzzzzz" > ><k...(a)att.bizzzzzzzzzzzz> wrote: > >> On Fri, 30 Apr 2010 18:39:21 -0700 (PDT), mpm <mpmill...(a)aol.com> wrote: > >> >On Apr 30, 4:31 pm, Wimpie <wimabc...(a)tetech.nl> wrote: > >> >> On 30 abr, 13:54, "mook johnson" <m...(a)mook.net> wrote: > > >> >> > "John Larkin" <jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote in message > > >> >> >news:ql9kt5tg7s7e5q7pb460gcdig4r00jjmrj(a)4ax.com... > > >> >> > > On Thu, 29 Apr 2010 18:30:41 -0500, "mook johnson" <m...(a)mook.net> > >> >> > > wrote: > > >> >> > >>Gents, > > >> >> > >>I looking for a consultant that can assist in the design of a custom > >> >> > >>military style connector with controlled characteristic impedance and > >> >> > >>insertion loss between two terminals in the 1MHz - 20MHz frequency range. > > >> >> > >>This connector is special because is the application so an off the shelf > >> >> > >>component will not work. > > >> >> > >>Any leads where I can start looking for such a consultant? > > >> >> > >>thanks > > >> >> > > There are so many military connectors, including ones for wild > >> >> > > environments, hermetic, etc, some standard part might work. > > >> >> > > 20 MHz isn't very demanding. Most any mil connector will be "matched" > >> >> > > to any impedance at 20 MHz. Wavelength is 15 meters! > > >> >> > > John > > >> >> > The connector I need goes into environments that far exceed military > >> >> > applications but the physical concept is similar. We have an in-house > >> >> > connector company that makes these connectors for us but they have never had > >> >> > to deal with never greater than >200KHz signals before. We tried using our > >> >> > regular connectors for this application and the impedance mismatch and > >> >> > insertion loss were extreme at 5 - 20MHz. The Zo mismatched by 50% and was > >> >> > not stable above 1MHz and had several resonant modes. Insertion loss > >> >> > something on the order is 6dB/connector and we'll have a couple dozen in > >> >> > series on this line. The number of series connection is the is the rub and > >> >> > it is unavoidable, non negotiable. > > >> >> > There are some commercial plastic connectors that tested very well (just to > >> >> > validate our test setup) with good impedance match/stability (+/- 5%) and > >> >> > low insertion loss (.1dB/connector) but they won't take the environment. > > >> >> > I'm looking for a consultant that can provide either of the following > > >> >> > 1) model a connector that is already designed but not made (basically review > >> >> > the in-house company proposed design) and simulate the high frequency > >> >> > response of the design. > > >> >> > 2) Give direction for the connector design based on constraints of material > >> >> > choices, physical size and geometry to meet the desired electrical signal > >> >> > characteristics while withstanding the environmental conditions. > > >> >> > The cut and try approach based on simple equations has a long cycle time. > >> >> > I'm looking to improve my chances of getting it right the first time. > > >> >> Hello Mook, > > >> >> When you have already a company that knows mechanical design and > >> >> reliability issues, you only need the EM-field guy. When you can > >> >> keep the mechanical guys and the EM-field guy in one room, this should > >> >> converge to a solution fast. > > >> >> One familiar with the concept of characteristic impedance, complex > >> >> propagation constant (contains both complex epsilon and permeability) > >> >> and know how to measure the material constants can do the job. > > >> >> What about: required Return Loss, characteristic impedance, Insertion > >> >> loss, propagation delay, size, cross section, (coaxial, square, > >> >> symmetrical, etc), peak and average power, etc? > > >> >> Kind regards, > > >> >> Wim > >> >> PA3DJSwww.tetech.nl > >> >> when you delete abc first, PM will reach me- Hide quoted text - > > >> >> - Show quoted text - > > >> >I have a question for you: > > >> >Do you believe that the characteristic impedance is dependent on the > >> >length of the coax? > >> >(For the ratio of transverse electric field to transverse magnetic > >> >field launched on a transmission line of infinite length.) > > >> "infinite length" <> "independent of length"- Hide quoted text - > > >> - Show quoted text - > > >Not sure I understand your cryptic post. > > >That is how characteristic impedance is classically defined, and I'm > >asking him if he believes that characteristic impedance is dependent > >on length? > > But you talk about dependency on length and "infinite" length in the same > paragraph. You can't have both variable length (which would include short) > and a dependency on being "infinite".- Hide quoted text - > > - Show quoted text - OK - Maybe I could have stated that a little better.... (?) My point: Does the length of the coax (or connector - since that's the topic of this post) have anything to do with characteristic impedance? And NOTE THAT THE DEFINITION OF CHARACTERISTIC IMPEDANCE ITSELF INCLUDES AN INFINITE LENGTH. (Which a connector DOES NOT have.) If I ask that question without mentioning that the various equations for characteristic impedance are derived from terms that include inductance per unit length (even if they later cancel out), then the question is absolutely meaningless. So, I am PURPOSELY avoiding any possibility of a circular definition when I ask this question. Do you understand now? Once you understand the question, we will look at whether or not the traditional equations for characteristic impedance are even valid (hint: I don't think they are!), given that they do not agree when applied to antennas, (which certainly have a length component). And, since they depend on antenna length, it contradicts the fundamental definitions. Even more interesting, the various calculations do not yield identical results, particularly if you consider an antenna to be a transmission line immersed in three-dimensional space. |