Activity for TonyStewartâ€
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Edit | Post #289547 |
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— | 8 months ago |
| Edit | Post #289547 |
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— | 8 months ago |
| Edit | Post #289547 |
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— | 8 months ago |
| Edit | Post #289547 | Initial revision | — | 8 months ago |
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A: Can the corner frequency of thermal noise change with change in source impedance? Any time you have a dielectric interface ( pF ) source resistance will always have an error in signal response until the electrode impedance is eqal or less than the sub-cutaneous impedance. This will affect the expected 1/f noise response. Your goal is to reduce Rs and increase Cs with gel and ... (more) |
— | 8 months ago |
| Comment | Post #287302 |
If "base voltage isn't applied" then Ib=0 & dIb=0 then the proposed formula with Ib is not logical. (more) |
— | 9 months ago |
| Comment | Post #288260 |
The slip is necessary for the rotor to generate the torque required for rotation. This force also draws more current. (more) |
— | 11 months ago |
| Comment | Post #288195 |
Otherwise using PWM pulsed energy to store power into a suitable inductor with CCM continuous drain you can match the average impedance with a circuit that does this with clamp protection where the % of drained current determines the reactive impedance as a voltage booster to a small stored capacito... (more) |
— | 11 months ago |
| Comment | Post #288195 |
Yes If 6V exceeds the reverse voltage rating on the PV then a diode is needed. When the voltage drops below 6V the energy is getting quite small % so harvesting under these conditions requires high impedance loads and there are custom IC's to do this with great effort for small reward.
Perhaps yo... (more) |
— | 11 months ago |
| Comment | Post #288225 |
Note: I just chose a small voltage with gain of -10 (more) |
— | 11 months ago |
| Edit | Post #288225 |
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— | 11 months ago |
| Comment | Post #288225 |
no. but you may want to define the purpose of the attenuator with a equation or function (more) |
— | 11 months ago |
| Edit | Post #288225 |
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— | 11 months ago |
| Edit | Post #288225 |
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— | 11 months ago |
| Edit | Post #288225 |
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— | 11 months ago |
| Edit | Post #288225 |
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— | 11 months ago |
| Edit | Post #288225 | Initial revision | — | 11 months ago |
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A: Confusion in operation of analog computer The two-terminal symbol for the attenuator comes from 3 pin potentiometer (pot.) referenced to 0V = "GND" Image alt text The summing amplifier is always inverting and gives you 3 options for gain which means internally it uses a 3 pin pot. to choose the gain for you based on the ratio of resist... (more) |
— | 11 months ago |
| Comment | Post #288010 |
@Carl That's good. It doesn't have to be the right leg either. It could be the hip or some other body part that doesn't move much. Then you can see what you are doing
with the lights on ;) (more) |
— | 11 months ago |
| Comment | Post #287952 |
Low impedances suppress high impedance E fields so very high impedance inputs do not easily attenuate. Also very low magnetic B fields can induce low current which as you know if you have a nano-amp per meter induced on a one megohm R you get a 1mV signal which is a 1000 times bigger than a microv... (more) |
— | 11 months ago |
| Comment | Post #288184 |
@#60854 SInce "no-load= open circuit" test, we are talking about mechanical load to a motor with zero torque load or electrical - no load when power is cut off to measure back EMF. (more) |
— | 11 months ago |
| Comment | Post #288183 |
Ensure there are no stored voltages on any pin when power is applied, including avoiding switch bounce.
To test an IC with power off one can apply 2Vac with a 10k to 100k series resistor to each pin to check for short circuits or ESD damage. The V-I plots may be shown in XY mode on any scope an... (more) |
— | 11 months ago |
| Edit | Post #288195 |
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— | 11 months ago |
| Edit | Post #288195 |
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— | 11 months ago |
| Edit | Post #288195 |
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— | 11 months ago |
| Edit | Post #288195 | Initial revision | — | 11 months ago |
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A: Over-voltage protection for device with photovoltaic cell source This IC is not well suited for the task. MPPT (Maximum Power Point Tracking) relies on matching impedance according to the maximum power transfer theorem. However, in the case of a photovoltaic array (PV), it functions as a current source with a voltage limit (Voc) and a short circuit limit (Isc).... (more) |
— | 11 months ago |
| Edit | Post #288185 | Initial revision | — | 11 months ago |
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A: What are these transformer graphs about? For R loads I is in phase with V. For L loads , V lags I up to 90 deg. For C loads, I lags V up to 90 deg. The trigonometric tangent angle is the ratio of impedance: Real to reactive. Your lectures or ref. book will give all the details. (more) |
— | 11 months ago |
| Edit | Post #288184 |
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— | 11 months ago |
| Edit | Post #288184 | Initial revision | — | 11 months ago |
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A: How is it possible to perform a open circuit test on a induction motor? In an open circuit test, also known as a no-load test, an induction motor is operated without any mechanical load connected to its shaft. The purpose of this test is to determine the no-load losses, core losses, and magnetizing current of the motor. General Purpose: efficiency and performance ... (more) |
— | 11 months ago |
| Edit | Post #288183 |
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— | 11 months ago |
| Edit | Post #288183 | Initial revision | — | 11 months ago |
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A: what should the output be for this use case of the CD4047 chip? Possibly it is damaged. Be ESD aware and do not power up with any voltage on any pins > 0.5V (Latchup failure) If raising p9 (reset) does not lower Q to logic "0"=<20% Vdd) replace the IC. No sweat, be more careful next time for handling failures of ESD etc. Most new IC failures are hand... (more) |
— | 11 months ago |
| Edit | Post #288036 | Initial revision | — | about 1 year ago |
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A: Why arc welding does not require high voltage to arc? - gas tubes, SCRs, and welder arcs all have negative incremental resistance. This means when conduction begins, the resistance drops like a crowbar and is sustained until the current drops below the holding current. - thus a typical ambient breakdown voltage for a sharp point of 1kV/mm is the sa... (more) |
— | about 1 year ago |
| Edit | Post #287969 |
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— | about 1 year ago |
| Comment | Post #288010 |
A good layout is one that meets or exceeds your expectations (or design specs). These specs form what is called Design for Manufacturability (DFM) for Testability (DFT) for cost (DFC) and for performance of accepting signal inputs by quick connection, signal conditioning for gain, bandwidth and CMRR... (more) |
— | about 1 year ago |
| Edit | Post #287969 |
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— | about 1 year ago |
| Edit | Post #287969 |
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— | about 1 year ago |
| Edit | Post #287969 |
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— | about 1 year ago |
| Edit | Post #287969 | Initial revision | — | about 1 year ago |
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A: What does it mean for a signal to have impedance? $$Z = R + jX $$ R is a real resistance that stores energy as heat and temperature rise which depends on the thermodynamic property of thermal resistance which is impacted by an enclosure to get hotter or cooler by forced airflow. Everything has some real resistance, even insulators with an elec... (more) |
— | about 1 year ago |
| Edit | Post #287952 | Initial revision | — | about 1 year ago |
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A: Testing instrumentation amplifier with differential signal It is important to realize that an ECG signal is high impedance and this easily picks up line voltage E-fields. Using a 50 Ohm sig.gen. is a poor simulation of the use of this circuit and also negates any common mode rejection using it as a single-ended amplifier with one input grounded. Ground by ... (more) |
— | about 1 year ago |
| Edit | Post #287524 |
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— | over 1 year ago |
| Edit | Post #287524 | Initial revision | — | over 1 year ago |
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A: What is the difference between rise/fall time and Turn-On/off Delay Time? To understand the timing, you must understand the cause. Delay is the time from input to output It is measured from +10% of input to 90% of output ( or a 10% change in output), unlike logic chips where the same voltage is used for input and output so delay is measured at Vdd/2 or 50% from input to... (more) |
— | over 1 year ago |
| Edit | Post #287523 | Initial revision | — | over 1 year ago |