diff --git a/content/book/morrison16_groun_shiel.md b/content/book/morrison16_groun_shiel.md index 8fe89a1..148b588 100644 --- a/content/book/morrison16_groun_shiel.md +++ b/content/book/morrison16_groun_shiel.md @@ -8,7 +8,7 @@ Tags : [Electronics]({{< relref "electronics" >}}) Reference -: ([Morrison 2016](#orgdb34704)) +: ([Morrison 2016](#orgc3a94fb)) Author(s) : Morrison, R. @@ -51,7 +51,7 @@ This displacement current flows when charges are added or removed from the plate ### Field representation {#field-representation} - + {{< figure src="/ox-hugo/morrison16_E_field_charge.svg" caption="Figure 1: The force field lines around a positively chaged conducting sphere" >}} @@ -64,18 +64,18 @@ This displacement current flows when charges are added or removed from the plate ### The force field or \\(E\\) field between two conducting plates {#the-force-field-or--e--field-between-two-conducting-plates} - + {{< figure src="/ox-hugo/morrison16_force_field_plates.svg" caption="Figure 2: The force field between two conducting plates with equal and opposite charges and spacing distance \\(h\\)" >}} ### Electric field patterns {#electric-field-patterns} - + {{< figure src="/ox-hugo/morrison16_electric_field_ground_plane.svg" caption="Figure 3: The electric field pattern of one circuit trace and two circuit traces over a ground plane" >}} - + {{< figure src="/ox-hugo/morrison16_electric_field_shielded_conductor.svg" caption="Figure 4: Field configuration around a shielded conductor" >}} @@ -88,7 +88,7 @@ This displacement current flows when charges are added or removed from the plate ### The \\(D\\) field {#the--d--field} - + {{< figure src="/ox-hugo/morrison16_E_D_fields.svg" caption="Figure 5: The electric field pattern in the presence of a dielectric" >}} @@ -148,9 +148,9 @@ In a few elements, the atomic structure is such that atoms align to generate a n The flow of electrons is another way to generate a magnetic field. The letter \\(H\\) is reserved for the magnetic field generated by a current. -Figure [6](#org4c94f50) shows the shape of the \\(H\\) field around a long, straight conductor carrying a direct current \\(I\\). +Figure [6](#org198efb1) shows the shape of the \\(H\\) field around a long, straight conductor carrying a direct current \\(I\\). - + {{< figure src="/ox-hugo/morrison16_H_field.svg" caption="Figure 6: The \\(H\\) field around a current-carrying conductor" >}} @@ -167,7 +167,7 @@ Ampere's law states that the integral of the \\(H\\) field intensity in a closed \boxed{\oint H dl = I} \end{equation} -The simplest path to use for this integration is the one of the concentric circles in Figure [6](#org4c94f50), where \\(H\\) is constant and \\(r\\) is the distance from the conductor. +The simplest path to use for this integration is the one of the concentric circles in Figure [6](#org198efb1), where \\(H\\) is constant and \\(r\\) is the distance from the conductor. Solving for \\(H\\), we obtain \begin{equation} @@ -179,7 +179,7 @@ And we see that \\(H\\) has units of amperes per meter. ### The solenoid {#the-solenoid} -The magnetic field of a solenoid is shown in Figure [7](#org7682896). +The magnetic field of a solenoid is shown in Figure [7](#org7535570). The field intensity inside the solenoid is nearly constant, while outside its intensity falls of rapidly. Using Ampere's law \eqref{eq:ampere_law}: @@ -188,7 +188,7 @@ Using Ampere's law \eqref{eq:ampere_law}: \oint H dl \approx n I l \end{equation} - + {{< figure src="/ox-hugo/morrison16_solenoid.svg" caption="Figure 7: The \\(H\\) field around a solenoid" >}} @@ -196,10 +196,10 @@ Using Ampere's law \eqref{eq:ampere_law}: ### Faraday's law and the induction field {#faraday-s-law-and-the-induction-field} When a conducting coil is moved through a magnetic field, a voltage appears at the open ends of the coil. -This is illustrated in Figure [8](#org431ab1d). +This is illustrated in Figure [8](#orgd2dee77). The voltage depends on the number of turns in the coil and the rate at which the flux is changing. - + {{< figure src="/ox-hugo/morrison16_voltage_moving_coil.svg" caption="Figure 8: A voltage induced into a moving coil" >}} @@ -237,7 +237,7 @@ The unit of inductance if the henry. -For the coil in Figure [7](#org7682896): +For the coil in Figure [7](#org7535570): \begin{equation} \label{eq:inductance\_coil} V = n^2 A k \mu\_0 \frac{dI}{dt} = L \frac{dI}{dt} @@ -432,24 +432,142 @@ Strain-gauge configuration, thermocouple grounding, and charge amplifiers are di ### Introduction {#introduction} +This chapter is devoted to analog circuits that operate below 100kHz. +The techniques that are described can be applied to audio amplifiers, power supplies as well as instrumentation. + +The availability of integrated circuits has simplified many aspects of analog circuit design. +Instrumentation must often handle long signal lines, reject ground potential differences, and maintain circuit stability. + +The general problem of analog design is called signal conditioning, which includes gain, filtering, offsets, bridge balancing, common-mode rejection, transducer excitation and calibration. +Once a signal has sufficient resolution and the bandwidth has been controlled, the signal can be digitized and transmitted over a digital link to a computer. +This chapter treats the problems of conditioning signals before they are sampled and recorded. + ### Instrumentation {#instrumentation} +There are many transducers that can measure temperature, strain, stress, position and vibration. +The signals generated are usually in the milli-volt range and must be amplified, conditioned, and then recorded for later analysis. -### History {#history} +
+
+ +It can be very difficult to verify that the measurement is valid. +For example, signals that overload an input stage can produce noise that may look like signal. + +
+ +
+
+ +1. **Reference Conductor**. + Any conductor used as the zero of voltage. + If a signal is measured with respect to a conductor called ground, it becomes the reference signal conductor. + In an analog circuit, there may be several reference conductors. +2. **Signal common / Signal ground** + A signal reference conductor. +3. **Balance signal(s)**. + Two signals measured with respect to a reference conductor whose sum is always zero. +4. **An unbalanced signal / A single-ended signal**. + A single voltage measured with respect to a reference conductor. +5. **Common-mode voltage**. + The average interfering voltage on a group of signal conductors measured with respect to a reference conductor. +6. **Normal-mode signal**. + The signal of interest. +7. **Differential signal / Difference signal**. + The voltage difference of interest. +8. **Instrumentation amplifier**. + A general-purpose differential amplifier with bandwidth from DC to perhaps 100kHz and variable gains from 1 to 5000. + +
### The basic shield enclosure {#the-basic-shield-enclosure} +Consider the simple amplifier circuit shown in Figure [9](#orgd60f7ec) with: + +- \\(V\_1\\) the input lead +- \\(V\_2\\) the output lead +- \\(V\_3\\) the conducting enclosure which is floating and taken as the reference conductor +- \\(V\_4\\) a signal common or reference conductor + +Every conductor pair has a mutual capacitance, which are shown in Figure [9](#orgd60f7ec) (b). +The equivalent circuit is shown in Figure [9](#orgd60f7ec) (c) and it is apparent that there is some feedback from the output to the input or the amplifier. + + + +{{< figure src="/ox-hugo/morrison16_parasitic_capacitance_amp.svg" caption="Figure 9: Parasitic capacitances in a simple circuit. (a) Field lines in a circuit. (b) Mutual capacitance diagram. (b) Circuit representation" >}} + +It is common practice in analog design to connect the enclosure to circuit common (Figure [10](#org412bfcb)). +When this connection is made, the feedback is removed and the enclosure no longer couples signals into the feedback structure. +The conductive enclosure is called a **shield**. +Connecting the signal common to the conductive enclosure is called "**grounding the shield**". +This "grounding" usually removed "hum" from the circuit. + + + +{{< figure src="/ox-hugo/morrison16_grounding_shield_amp.svg" caption="Figure 10: Grounding the shield to limit feedback" >}} + +Most practical circuits provide connections to external points. +To see the effect of making a _single_ external connection, open the conductive enclosure and connect the input circuit common to an external ground. +Figure [11](#org5d67d92) (a) shows this grounded connection surrounded by an extension of the enclosure called the _cable shield_. +A problem can be caused by an incorrect location of the connection between the cable shield and the enclosure. +In Figure [11](#org5d67d92) (a), the electromagnetic field in the area induces a voltage in the loop and a resulting current to flow in conductor (1)-(2). +This conductor being the common ground that might have a resistance \\(R\\) or \\(1\,\Omega\\), this current induced voltage that it added to the transmitted signal. +Our goal in this chapter is to find ways of keeping interference currents from flowing in any input signal conductor. +To remove this coupling, the shield connection to circuit common must be made at the point, where the circuit common connects to the external ground. +This connection is shown in Figure [11](#org5d67d92) (b). +This connection keeps the circulation of interference current on the outside of the shield. + +There is only one point of zero signal potential external to the enclosure and that is where the signal common connects to an external hardware ground. +The input shield should not be connected to any other ground point. +The reason is simple. +If there is an external electromagnetic field, there will be current flow in the shield and a resulting voltage gradient. +A voltage gradient will couple interference capacitively to the signal conductors. + +
+
+ +An input circuit shield should connect to the circuit common, where the signal common makes its connection to the source of signal. +Any other shield connection will introduce interference. + +
+ +
+
+ +Shielding is not an issue of finding a "really good ground". +It is an issue of using the _right_ ground. + +
+ + + +{{< figure src="/ox-hugo/morrison16_enclosure_shield_1_2_leads.png" caption="Figure 11: (a) The problem of bringing one lead out of a shielded region. Unwanted current circulates in the signal lead 2. (b) The \\(E\\) field circulate current in the shield, not in the signal conductor." >}} + ### The enclosure and utility power {#the-enclosure-and-utility-power} +When utility power is introduced into an enclosure, a new set of problems results. +The power transformer couples fields from the external environment into the enclosure. +The obvious coupling results from capacitance between the primary coil and the secondary coil. +Note that the secondary coil is connected to the circuit common conductor. + + + +{{< figure src="/ox-hugo/morrison16_power_transformer_enclosure.png" caption="Figure 12: A power transformer added to the circuit enclosure" >}} + ### The two-ground problem {#the-two-ground-problem} ### Instrumentation and the two-ground problem {#instrumentation-and-the-two-ground-problem} +The basic analog problem is to condition a signal associated with one ground reference potential and transport this signal to a second ground reference potential without adding interference. + + + +{{< figure src="/ox-hugo/morrison16_two_ground_problem.svg" caption="Figure 13: The two-circuit enclosures used to transport signals between grounds" >}} + ### Strain-gauge instrumentation {#strain-gauge-instrumentation} @@ -462,6 +580,10 @@ Strain-gauge configuration, thermocouple grounding, and charge amplifiers are di ### The basic low-gain differential amplifier (forward referencing amplifier) {#the-basic-low-gain-differential-amplifier--forward-referencing-amplifier} + + +{{< figure src="/ox-hugo/morrison16_low_gain_diff_amp.svg" caption="Figure 14: The low-gain differential amplifier applied to the two-ground problem" >}} + ### Shielding in power transformers {#shielding-in-power-transformers} @@ -474,6 +596,24 @@ Strain-gauge configuration, thermocouple grounding, and charge amplifiers are di ### Signal flow paths in analog circuits {#signal-flow-paths-in-analog-circuits} +
+
+ +Here are a few rule that will help in analog board layout: + +1. Maintain a flow of signal and signal common from input to output. + The area between the signal path and the signal reference conductor should be kept small. +2. Components associated with the input should not be near output circuit components. +3. Power supply connections (DC voltages) should enter at the output and thread back toward the input. + This avoids common-impedance coupling (parasitic feedback). +4. The greatest attention should be paid to the input circuit geometry. + Lead length for components connecting to the input path should be kept short. + Another way of describing this requirements is to interconnect the components to minimize the amount of bare copper connected to the input signal path. +5. Feedback summing points are critical. + Keep lead lengths short at these nodes. + +
+ ### Parallel active components {#parallel-active-components} @@ -483,6 +623,14 @@ Strain-gauge configuration, thermocouple grounding, and charge amplifiers are di ### Feedback theory {#feedback-theory} + + +{{< figure src="/ox-hugo/morrison16_basic_feedback_circuit.svg" caption="Figure 15: The basic feedback circuit" >}} + + + +{{< figure src="/ox-hugo/morrison16_LR_stabilizing_network.svg" caption="Figure 16: An LR-stabilizing network" >}} + ### Output loads and circuit stability {#output-loads-and-circuit-stability} @@ -501,6 +649,44 @@ Strain-gauge configuration, thermocouple grounding, and charge amplifiers are di ### Charge converter basics {#charge-converter-basics} +In vibration analysis, piezoelectric sensors are used which are electrically equivalent to a capacitor. +When a force is exerted to the piezoelectric material, charges or voltage are generated. +The relationship between charge and voltage is \\(V = Q/C\\) where \\(C\\) is the transducer capacitance. + +The voltage on the transducer can be amplifier by a high-impedance amplifier. +The input cable capacitance attenuates the input signal and this makes calibration a function of cable length. +The preferred method of amplifying signals from piezoelectric transducers is to measure charge generation and not voltage generation. +The charge is first converted to a voltage and the voltage is then amplified. +This type of instrument is called a **charge amplifier**. + +The basic feedback around an operational amplifier usually involves two resistors. +The voltage gain is simply the ratio of the two resistors. +If the resistors are replaced by capacitors, the gain is the ratio of reactances. +This feedback circuit is called a **charge converter**. +The charge on the input capacitor is transferred to the feedback capacitor. +If the feedback capacitor is smaller than the transducer capacitance by a factor of 100, then the voltage across the feedback capacitor will be 100 times greater than the open-circuit transducer voltage. +This feedback arrangement is shown in Figure [17](#org964dc8b). +The open-circuit input signal voltage is \\(Q/C\_T\\). +The output voltage is \\(Q/C\_{FB}\\). +The voltage gain is therefore \\(C\_T/C\_{FB}\\). +Note that there is essentially no voltage at the summing node \\(s\_p\\). + +
+
+ +A charge converter does not amplifier charge. +It converts a charge signal to a voltage. + +
+ + + +{{< figure src="/ox-hugo/morrison16_charge_amplifier.svg" caption="Figure 17: A basic charge amplifier" >}} + + + +{{< figure src="/ox-hugo/morrison16_charge_amplifier_feedback_resistor.svg" caption="Figure 18: The resistor feedback arrangement to control the low-frequency response" >}} + ### DC power supplies {#dc-power-supplies} @@ -542,6 +728,55 @@ Solar winds can disrupt power distribution and damage oil pipelines. ### Semantics {#semantics} +Here are the key words used by a power engineer as defined by the NEC: + +Ground +: + + +Equipment ground +: + + +The grounded conductor +: + + +The ungrounded conductor +: + + +Neutral +: + + +Isolated ground +: + + +Service entrance +: + + +Grounding electrode system +: + + +Feeder circuit +: + + +Branch circuit +: + + +Separately derived power +: + + +Listed equipment +: + ### Utility power {#utility-power} @@ -699,6 +934,36 @@ Methods for limiting field penetration into and out of a screen are offered. ### Cables with shields {#cables-with-shields} +In analog work, an aluminum foil is often used as a shield around a cable. +The inside of the aluminum foil is anodized to provide protection against corrosion. +Because it is difficult to terminate the foil at the cable ends, a drain wire is provided on the outside of the cable foil. +This drain wire is made of multistranded tinned copper wires that make contact with the foil along the length of the cable. +If the foil should break, the drain wire connects the segments together. + +In audio work, where a cable carries a microphone signal, the cable can be a shielded single conductor. +In instrumentation, best practice requires that the signal common and the shield be separate conductors. + +An aluminum foil over a group of conductors provides an **excellent electrostatic shield at low frequencies**. +In analog work, the shield should be connected at one end to the reference conductor preferable where it connects to a ground. +If the drain wire is connected to grounded hardware at both ends, then interference can result. +Electromagnetic fields in the area will cause current flow in the resulting loop. + +A foil seam does not allow current to flow freely around the cable. +Also the foil doesn't form a very stable geometry. +For these reasons, foil shields should not be used where the characteristic impedance of the cable needs to be controlled. +The termination of shields at a hardware interface can be critical. +A cable terminated by a drain wire allows field energy to penetrate the hardware at the hardware at the connector. +A woven braid can provide 360 degree termination. + +The term coax is generally applied to cable where the characteristic impedance is controller. +A typical coax is a single conductor surrounded by a shield with a controlled geometry. +For applications from DC to about 1MHz, the characteristic impedance may not be important. +Above this frequency, coaxial cables is preferred. +The manufacturer supplies specifications relating to signal loss at high frequencies. + +The characteristic impedance of a transmission line is a function of the conductor geometry and of the dielectric constant. +To transport RF power without reflections, the source impedance and the terminating impedance must match the line impedance. + ### Low-noise cables {#low-noise-cables} @@ -768,4 +1033,4 @@ Methods for limiting field penetration into and out of a screen are offered. ## Bibliography {#bibliography} -Morrison, Ralph. 2016. _Grounding and Shielding: Circuits and Interference_. John Wiley & Sons. +Morrison, Ralph. 2016. _Grounding and Shielding: Circuits and Interference_. John Wiley & Sons. diff --git a/static/ox-hugo/morrison16_LR_stabilizing_network.svg b/static/ox-hugo/morrison16_LR_stabilizing_network.svg new file mode 100644 index 0000000..3841df1 --- /dev/null +++ b/static/ox-hugo/morrison16_LR_stabilizing_network.svg @@ -0,0 +1,1318 @@ + + + + + + image/svg+xml + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + diff --git a/static/ox-hugo/morrison16_basic_feedback_circuit.svg b/static/ox-hugo/morrison16_basic_feedback_circuit.svg new file mode 100644 index 0000000..d788384 --- /dev/null +++ b/static/ox-hugo/morrison16_basic_feedback_circuit.svg @@ -0,0 +1,1736 @@ + + + + + + image/svg+xml + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + diff --git a/static/ox-hugo/morrison16_charge_amplifier.svg b/static/ox-hugo/morrison16_charge_amplifier.svg new file mode 100644 index 0000000..6bbd535 --- /dev/null +++ b/static/ox-hugo/morrison16_charge_amplifier.svg @@ -0,0 +1,5311 @@ + + + + + + image/svg+xml + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + diff --git a/static/ox-hugo/morrison16_charge_amplifier_feedback_resistor.svg b/static/ox-hugo/morrison16_charge_amplifier_feedback_resistor.svg new file mode 100644 index 0000000..de77d8b --- /dev/null +++ b/static/ox-hugo/morrison16_charge_amplifier_feedback_resistor.svg @@ -0,0 +1,1404 @@ + + + + + + image/svg+xml + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + diff --git a/static/ox-hugo/morrison16_enclosure_shield_1_2_leads.png b/static/ox-hugo/morrison16_enclosure_shield_1_2_leads.png new file mode 100644 index 0000000..5389102 Binary files /dev/null and b/static/ox-hugo/morrison16_enclosure_shield_1_2_leads.png differ diff --git a/static/ox-hugo/morrison16_grounding_shield_amp.svg b/static/ox-hugo/morrison16_grounding_shield_amp.svg new file mode 100644 index 0000000..43749d4 --- /dev/null +++ b/static/ox-hugo/morrison16_grounding_shield_amp.svg @@ -0,0 +1,1513 @@ + + + + + + image/svg+xml + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + diff --git a/static/ox-hugo/morrison16_low_gain_diff_amp.svg b/static/ox-hugo/morrison16_low_gain_diff_amp.svg new file mode 100644 index 0000000..8fa50e4 --- /dev/null +++ b/static/ox-hugo/morrison16_low_gain_diff_amp.svg @@ -0,0 +1,1684 @@ + + + + + + image/svg+xml + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + diff --git a/static/ox-hugo/morrison16_parasitic_capacitance_amp.svg b/static/ox-hugo/morrison16_parasitic_capacitance_amp.svg new file mode 100644 index 0000000..fd6ff0c --- /dev/null +++ b/static/ox-hugo/morrison16_parasitic_capacitance_amp.svg @@ -0,0 +1,2035 @@ + + + + + + image/svg+xml + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + diff --git a/static/ox-hugo/morrison16_power_transformer_enclosure.png b/static/ox-hugo/morrison16_power_transformer_enclosure.png new file mode 100644 index 0000000..5dd122c Binary files /dev/null and b/static/ox-hugo/morrison16_power_transformer_enclosure.png differ diff --git a/static/ox-hugo/morrison16_two_ground_problem.svg b/static/ox-hugo/morrison16_two_ground_problem.svg new file mode 100644 index 0000000..f089fdc --- /dev/null +++ b/static/ox-hugo/morrison16_two_ground_problem.svg @@ -0,0 +1,2280 @@ + + + + + + image/svg+xml + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +