Tony Stewart EE since 1975

The two calculators communicated over long distance LD Data sets. (RS-485) and the master to a smart dual page HP terminal to look like a spreadsheet of experiment states or voltages with inverse video cells for tolerance issues. ( Another SCADA project before SCADA was even an acronym) But I know software guys who like you rolled all their own drivers in machine code.

The other used two HP9825 calculators whereI wrote the drivers for DMA with an synchronous frame of 96 channels every second and an asynchronous command/data loop for 96 command channels including remote control of 10 power supplies over long umbilical with remote voltage sensing.

@Lundin I do not ever consider myself a programmer but back in the 70's I had a couple major projects. One include a dozen boards one being a discrete TTL UART before the 1st IC was released. It was FDX and all the error flags, buffers and parity for my 1st SCADA project.

Imagine laying out an SoC or IoT or PIC like chip automatically with full optimization and max utilization with open software. Thanks to Cypress and google its now free. theopenroadproject.org

A floating input might cause interference or get damaged

suppress EMI damage from overvoltage > 5mA or oscillating input from stray feedback. or finger touch . use 10k

@NickAlexeev if you had specs for DCR and RdsOn , and commutation frequency max for eddy current losses, one might be able to estimate for a tested Motor, otherwise, not. DC and low frequency losses are the dominant loss unless operating near max RPM with minimal load. eddy current losses are Vf^2 and not affected by current, so load ratio specs are needed.

@W5VO i have seen many Moderation misunderstandings that are never resolved properly with 2 way communication. It's always 1 way or the highway.

Been there . Done that.

Thus lower Z axis acceleration. Gcode Panel can do that for free.

Then you don't have a chance to meet specs. Use Z axis fractional positioning then with microsteps but lower torque. If you have a spindle head, then use a bigger bearing.

@TQQQ laserfocusworld.com/white-papers/whitepaper/14233425/…

every power up and every change of 5'C a recal was done as it affected overshoot in the servo feedback system

that is why recalibration was done with temperature compensation for Rotary actuator Force constant due to Mu variation

based on tests done with Fujitsu HDD division

but my system would be far more accurate than a magnet based on my SmCo experience with HDD rotary motors

using motion

but for Alum purity affects coupling free of Fe so viscous force is more accurate

to measure 1um flaws inside Monel steel.

Best case 60dB SNR with PLL's

@TQQQ if calibrated accurately, maybe as mu is very temperature dependent. I have used ferrite Eddy Current measurements to detect 1mm with 12 bit accuracy and > 40 dB SNR with sin/cos at 100k/200kHz

@TQQQ FWIW look up laser interferometry

with adjustments to machine .The surface table was used and large so $$=?

I know a friend who used that for measuring the sharpness of a blade sharpness and coplanarity using interferometry for a steel sheer blade

That is the wavelength of 1 cycle of Infrared

That is a 1 micron resolution. Can you guarantee the reference point is that stable? Then I might use interferometry with a Bragg reflector or Fresnel plastic sheet and a laser reflector to count cycles relative to a fixed datum reflector

10cm 10 m?

You still never gave accuracy or range of 10 bits

What's wrong with a depth gauge

alum. is not magnetic when still

Laser deflection is possible from a mirror or repeatable image

@Lundin Umm .. no, That's why you cannot get contacts rated over 2A with gold. They are only all flashed on contacts rated <= 2 A to prevent oxide. So no go even on alibaba

the coil needs a diode for flyback clamp

gold contacts will burn off if >2A, you need a silver alloy @Lundin

Why do you need such a small box? The boards are small enough. encrypted-tbn3.gstatic.com/… but good soldering safe if strong

Since the POR state is undefined and no S/R inputs it should not matter if the output is Q or Q#. It will pull high or low . High turning on NPN and Low turning OFF.

digikey.ca/en/products/filter/flip-flops/…

By positive you mean "Q" Here is an inverted output "Qbar" ti.com/lit/ds/sces221s/sces221s.pdf

Yes 1 T or D FF as I showed

No, They are complementary so they pull both high and low. I also showed one with dual outputs Q, Q#

When I started working in the 70's my musician buddy had a blown synth with 30 CMOS IC's and all the p/n's sanded off. it took me 2 hrs to fix it. So if you want it fixed, give more details.

Thank you. This is important to know if you want accurate answers. Flyback voltages from dry contact disconnection on the positive side, will then produce negative voltage and may damage to any chip here. A series diode can block that. But more info is still needed.

I am wondering why you need this info. Pls Advise.

OK see what I mean about photo quality. yes 5 pin but a trace goes under it probably to Pin 2 on datasheet and looking almost like i.stack.imgur.com/aJWNh.png

If you see a physical lead then show it on logic schematic with no connection. The photo says it has 6 leads which is important info to match part, but is unreadable for surface reflection of numbers which is also important info. The convention for pin numbers, now you know, is left to right and CCW top view from dot for pin 1. Connectors may have different rules than IC's.

@Carl yes but that isn't needed here. SNR is OK just lack of sensitivity

Driven Right Leg (DRL) feedback, which means the common-mode rejection ratio may not be so high... not that is not true and your SNR is good in muscle trace . The INA has a CMRR >> 100 dB

Markup the schematic to show actual results of voltage and values of R

Vref must be near Vcc/2 so check your voltage and values i.stack.imgur.com/Gxugk.png. Like 1.5V for 3.3V is OK. Electrode contact and placement is also important. 50 Hz noise is large when not connected properly

I was looking a similar schematic with different values , sorry