Test Equipment Anonymous (TEA) group therapy thread

[beanflying]

@beanflying, do you think it is the 34401 or the source is the major 'drifter'?

Based on other testing against ovenised or references in my chamber it is the 34401A at 2PPM'ish/5C. When it and my 34461A get their Cal done in a few weeks I will be doing some more careful testing over time/temp. The 335D is by comparison more stable and even the little Fluke 515A holds up well and is better than the Agilent.

When I get my Ender Enclosure/fridge sorted out it will have he ability to be held warm against lower ambients so post Autumn it will be possible to drop entire meters in it and hold them stable, on edge I think it will even take the 335D  There will be some gentle fan extraction/circulation and some low power elements in it for 3DP work with some of the tougher filaments. In theory I could fit up a smaller Peltier Cooler option to it for up or down but I hadn't planned to.

EDIT Checked 335D/34401A after a short 'warm up'  37 C and dropped 5PPM from the 47C.

[tautech]

Star-Delta Starters only reduce startup currents, DOL (Direct online) should be fine for your job but would be different if you were starting it say 10+ times an hour it might help the motor temps. For bigger motors electronic soft starters were taking the place of Star-Delta when I got out of the pump industry.

30+C ambient your motor would be plenty toasty and the internal smoke might see an appearance 

Great thanks.

Yeah, we'll strangle it some to take the load off the motor and get back into its happy place.
ATM, just 1 hr runs with zero restarts.

If it is possible to start up with an open circuit for the water flow, i.e. the pump is able to start up trying to pump air only for the first 2 or 3 seconds and then water is introduced automatically, the start up current would be greatly reduced and thus the temperature will be reduced at the time.

Actually not right no back pressure open flow is far more power required and can also lead to NPSH (inlet) and priming issues. NPSH is an actual technical thing but if you asked about it to most selling Ag pumps the industry joke was 'No Pumps Sold Here'  Single starts like Tautech has heat from starting is minor.

Spec, centrifugal pumps must be fully wet all the times and flow rate determines the load on the motor as Bean says.
We've got a handle on what needs to be done, just need the time and a clear head on how best to do it. 
--------------------
Under the weather after a mates sons wedding.   

[Specmaster]

Star-Delta Starters only reduce startup currents, DOL (Direct online) should be fine for your job but would be different if you were starting it say 10+ times an hour it might help the motor temps. For bigger motors electronic soft starters were taking the place of Star-Delta when I got out of the pump industry.

30+C ambient your motor would be plenty toasty and the internal smoke might see an appearance 

Great thanks.

Yeah, we'll strangle it some to take the load off the motor and get back into its happy place.
ATM, just 1 hr runs with zero restarts.

If it is possible to start up with an open circuit for the water flow, i.e. the pump is able to start up trying to pump air only for the first 2 or 3 seconds and then water is introduced automatically, the start up current would be greatly reduced and thus the temperature will be reduced at the time.

Actually not right no back pressure open flow is far more power required and can also lead to NPSH (inlet) and priming issues. NPSH is an actual technical thing but if you asked about it to most selling Ag pumps the industry joke was 'No Pumps Sold Here'  Single starts like Tautech has heat from starting is minor.

Spec, centrifugal pumps must be fully wet all the times and flow rate determines the load on the motor as Bean says.
We've got a handle on what needs to be done, just need the time and a clear head on how best to do it. 
--------------------
Under the weather after a mates sons wedding.   

Haha been there and got the T shirt[emoji6]

[GreyWoolfe]

Right on brotha and thanks for the shared kindness...I miss the hell out of central Florida. I grew up in Daytona Beach over on the Eastern coast and still dream about getting back to the salty-humid air and occasional fun surf.

You come to the DB area and I will be happy to treat you to a tasty beverage.

[bd139]

Random hack. I HATE arduinos with a passion. They are a stinking turd of a platform which has been poking me in the eye a lot. I've been buying them by the bucket load to use as AVR dev boards because I'm lazy. Bare metal AVR + gcc is good. Thus I threw together a minimal dev board to use with a USBasp programmer and with an optional 5v power supply. Stuff one header and the AVR on and job done.



First LED flash today on first board rev with a mega88p. Kicad FTW 

Currently awaiting some proper Racal OCXO upgrade PCBs from JLC as well. That should tidy up that hack board I built. Making PCBs is perhaps too much fun.

[SilverSolder]

I HATE arduinos with a passion.

Board looks cool!  -  but I don't understand what there is to hate about Arduinos, not much on one of those - and you can't beat buying working microcontroller boards for around a dollar each?

[bd139]

Arduino choice is what shoots me. You get to pay through the nose for an official board, risk it with a shonky one which has a 50/50 of not even working or having driver issues due to some weird serial chip, don't get to choose which oscillator you get to use, no opportunity for cost optimisation. On the pro minis you cant break out the ADC reference so can't optimise that out. Then if you decide to use the toolchain you enter a world of pain. Interrupts - ahhahahahhahahahaha GTFO.

[tggzzz]

Just for our very own Anne McCaffrey fan...
https://newsthump.com/2019/03/01/flags-with-dragons-on-just-cooler-confirms-science/

[mnementh]

Random hack. I HATE arduinos with a passion. They are a stinking turd of a platform which has been poking me in the eye a lot. I've been buying them by the bucket load to use as AVR dev boards because I'm lazy. Bare metal AVR + gcc is good. Thus I threw together a minimal dev board to use with a USBasp programmer and with an optional 5v power supply. Stuff one header and the AVR on and job done.

   First LED flash today on first board rev with a mega88p. Kicad FTW 

Currently awaiting some proper Racal OCXO upgrade PCBs from JLC as well. That should tidy up that hack board I built. Making PCBs is perhaps too much fun.

I have one of these from back in the prehistoric dayz of RC, when ESCs still used Atmega8. They were a godsend back then; but now everything's moved to faster, smarter chips to support telemetry and hardware PWM generation instead of bit-banging.

I keep it around, just in case I need to read the FW off one in situ for some random application.  HobbyKing no longer carries them, but if you like, I can put out a want-ad on RCGroups to see if anybody has one they want to get rid of.

mnem
*Off to meet his doom/dentist*

[mnementh]

Arduino choice is what shoots me. You get to pay through the nose for an official board, risk it with a shonky one which has a 50/50 of not even working or having driver issues due to some weird serial chip, don't get to choose which oscillator you get to use, no opportunity for cost optimisation. On the pro minis you cant break out the ADC reference so can't optimise that out. Then if you decide to use the toolchain you enter a world of pain. Interrupts - ahhahahahhahahahaha GTFO.

I've bought more knockoff Arduino Nanos than I can count. Only ones I EVER had a problem with were ones that  FTDI DELIBERATELY FUCKED the serial with a firmware "update".

First round of "bricking" I replaced about 5 FT232RLs at a cost of ~$10 total. Second round I just bought new knockoff Nanos, lifted the write-enable pin on the FT232RL, then went on about my business and FUCK FTDI with a shovel!

CH340 now has a signed driver... they're cheap as chips, and mostly what the knock-offs are using now.  Just look for that and you'll have no problems.

It's not Rocket Surgery... it's just one of those "joys of globalization" we were talking about earlier. 

mnem

[mnementh]

Just for our very own Anne McCaffrey fan...
https://newsthump.com/2019/03/01/flags-with-dragons-on-just-cooler-confirms-science/

Eeehhh... I wouldn't go that far. I grew up a bit since I chose that avatar; the problem is, mnem has a life of his own. I really loved the first trilogy as a youth... but later stuff of hers devolved into a morass of internecine politics and espionage that just made my brain hurt. We are a proper Welsh Red IRL (Edwards Clan tartan and e'eythang), but online the bronze skin just sort of won't die, without killing everything else "mnem".

I'm down with him having his own life. I'm busy raising our hatchlings kids.

mnem

[bd139]

Arduino choice is what shoots me. You get to pay through the nose for an official board, risk it with a shonky one which has a 50/50 of not even working or having driver issues due to some weird serial chip, don't get to choose which oscillator you get to use, no opportunity for cost optimisation. On the pro minis you cant break out the ADC reference so can't optimise that out. Then if you decide to use the toolchain you enter a world of pain. Interrupts - ahhahahahhahahahaha GTFO.

I've bought more knockoff Arduino Nanos than I can count. Only ones I EVER had a problem with were ones that  FTDI DELIBERATELY FUCKED the serial with a firmware "update".

First round of "bricking" I replaced about 5 FT232RLs at a cost of ~$10 total. Second round I just bought new knockoff Nanos, lifted the write-enable pin on the FT232RL, then went on about my business and FUCK FTDI with a shovel!

CH340 now has a signed driver... they're cheap as chips, and mostly what the knock-offs are using now.  Just look for that and you'll have no problems.

It's not Rocket Surgery... it's just one of those "joys of globalization" we were talking about earlier. 

mnem

I've had some hell.

The worst one was a clone uno I had controlling two 80mm fans to blow some tomato seedlings back and forth to make them stronger (yes I am that lazy). Came back and it had gone phut, both fans on full whack. Tomatoes battered. Thought it was a software problem ie WDT hung it but alas no, no response. Then I found that the cheap ass AMS1117 clone they had put on it had gone in/out short and blown the crap out of the AVR. So I got that swapped out, checked it over, added some zener clamps in case it was a voltage spike. Lasted two days then the AMS1117 blew up again! Fuuu. Then I bought a third one amazon same day and that had a missoldered CH340 on it. Fixed that and it was dead anyway. Got that swapped out next day and that worked (still got that somehwere). Got a cheap Pro mini clone in there from bitsbox.co.uk which lasted for the rest of the season thank feck.

I also lost a USB port on my old desktop to a clone uno 

And the IDE. Kill me with a dull spoon rather than make me use that again. You couldn't add more clunk if you really put your back into it.

My solution - no CH340, no FTDI!

[mnementh]

Arduino choice is what shoots me. You get to pay through the nose for an official board, risk it with a shonky one which has a 50/50 of not even working or having driver issues due to some weird serial chip, don't get to choose which oscillator you get to use, no opportunity for cost optimisation. On the pro minis you cant break out the ADC reference so can't optimise that out. Then if you decide to use the toolchain you enter a world of pain. Interrupts - ahhahahahhahahahaha GTFO.

I've bought more knockoff Arduino Nanos than I can count. Only ones I EVER had a problem with were ones that  FTDI DELIBERATELY FUCKED the serial with a firmware "update".

First round of "bricking" I replaced about 5 FT232RLs at a cost of ~$10 total. Second round I just bought new knockoff Nanos, lifted the write-enable pin on the FT232RL, then went on about my business and FUCK FTDI with a shovel!

CH340 now has a signed driver... they're cheap as chips, and mostly what the knock-offs are using now.  Just look for that and you'll have no problems.

It's not Rocket Surgery... it's just one of those "joys of globalization" we were talking about earlier. 

mnem

I've had some hell.

The worst one was a clone uno I had controlling two 80mm fans to blow some tomato seedlings back and forth to make them stronger (yes I am that lazy). Came back and it had gone phut, both fans on full whack. Tomatoes battered. Thought it was a software problem ie WDT hung it but alas no, no response. Then I found that the cheap ass AMS1117 clone they had put on it had gone in/out short and blown the crap out of the AVR. So I got that swapped out, checked it over, added some zener clamps in case it was a voltage spike. Lasted two days then the AMS1117 blew up again! Fuuu. Then I bought a third one amazon same day and that had a missoldered CH340 on it. Fixed that and it was dead anyway. Got that swapped out next day and that worked (still got that somehwere). Got a cheap Pro mini clone in there from bitsbox.co.uk which lasted for the rest of the season thank feck.

I also lost a USB port on my old desktop to a clone uno 

And the IDE. Kill me with a dull spoon rather than make me use that again. You couldn't add more clunk if you really put your back into it.

My solution - no CH340, no FTDI!

You haven't spent much time working with JTAG serial, have you?    Makes EVERYTHING Ardu feel like silk. 



Hey... I tripped over this today and immediately thought of you and Med's MANY discussions on "bosses" and "employment" in general... 

mnem
https://youtu.be/K1BHuYOb8fM

[bd139]

I did Xilinx FPGA stuff in the distant past. I know about JTAG unfortunately. That’s one thing that put me off STM32.

As for bosses. I disagree with all of them. No one is my boss, no one is my leader. I let them think they are when it suits my end game

[mnementh]

 All the little fiddly bits...

         

So... one of the things none of the "UFixit" articles and videos tells you about is the BS involved in moving your HOME button to the new screen; they just casually scrape the old one off and plop it down on the new glass. Well, of course, if you want the damned thing to work RIGHT, it's never that easy.

On the current models and the iPad Air 2, things are a bit more complicated.

First; if you look immediately to the left of the button, thee is a little bit of black tape. Under that, there is a bit of FPC with a sensor chip on it; this detects the smart cover and must be transferred over. It is a soldered connection, with fiddly little location windows approx 0.5mm square you have to align just right so you get the tiny little solder pads soldered to each other and not their neighbor. 

Next, if you look on top of the button itself, there is a little metal bridge that actually is both a stop, and what the tactile button actuates against. This has NO SUPPORT under it from the body of the iPad like earlier models; it is held to the glass with hot glue and has to be able to withstand the full force of every 9-year-old and her gorilla brother jabbing their thumbs into it with all their might.  Just "sticking it down" is NOT gonna work; you need to use hot-glue or epoxy.   

To their credit, iFixIt's article DOES warn you about this one... but what they don't warn you about is the button itself. It has a spacer integrated into it, and if the adhesive doesn't come away perfectly (or in my case, at all) you need to glue it back down and seal it some other way or you'll have dust ingress. You can buy the gasket with new adhesive; but that doesn't do you any good for the spacer.

I spent some time trying to make this all work with some of the replacement screen sealing tape I got with my repair kit... but after fiddling around with it for over an hour, once assembled the spacing was wrong and the home button was depressed all the time.

I then contrived to glue the spacer down the hard way; with a tiny bit of silicone RTV sealant spread around using a needle. So here comes the next fiddly bit: I damaged the spacer a bit getting it off, and it's no longer flat. Silicone RTV has no glue strength until it is fully cured; even then, gaps make it weak. It really only works right when things are perfectly flat surface against perfectly flat surface.

So I thought long & hard, tried lots of massaging with rolling and flat-billed pliers; no joy. Then, when I was watching an ep of "Clone Wars" with my son, it struck me: I need to sandwich it between two perfectly flat plates of some sort, and apply moderate heat. While I was rummaging around the back room for bits of metal to do this with, I turned around and saw my Tornado and it clicked. Everything I needed was right there, already set up for me! That little spacer is under there, right in the middle. I put the clips back on the plate, ran the bed up to 70°C for a couple episodes, then let it cool completely. Voila! Perfectly flat again!

Just before bedtime I cleaned and glued the spacer down. This morning, I did the same silicone fiddly-bit with the rubber gasket, gluing it to the spacer; next will come hot-gluing the metal bridge down, and hopefully I can get on with actually installing the new screen. 

So; just goes to show you: you CAN do something USEFUL with a 3D Printer; it's not just about making little obscene gestures and things with boobies out of plastic! 

mnem
"A true mechanic uses all tools at his disposal." ~ grand-dad

[mnementh]

I did Xilinx FPGA stuff in the distant past. I know about JTAG unfortunately. That’s one thing that put me off STM32.

As for bosses. I disagree with all of them. No one is my boss, no one is my leader. I let them think they are when it suits my end game

The STM32F family all have an embedded ST Link-USB controller; the ST-Link Debugger software suite installs a signed driver and connects directly to it. From there it's the STM ODE, which should be pretty familiar.

There are also a number of bits of software that will talk directly to it for multirotor model aircraft; and since the bootloader is stored in protected space, you don't have to worry about wiping out your connectivity to the thing by accident. You could try reverse-engineering some of them; the UI is well-developed and pretty slick for most of them at this point. Some even leverage the MS HID connectivity API.

Older STM32-based flight controllers are cheap; giveaway cheap. They'll come with a built-in 5V regulator, a number of pins broken out to be used as PWM outputs, as well as preinstalled connectivity to several UARTs and ADC or multifunction pins, plus will have gyro/accelerometer and sometimes GPS/Magnetometer/baro sensors as well. I'll see if I can find some of my older FCs I can send you to tinker with. It's not like any of them will ever fly again.

mnem
*Time to get the kiddles*

[bd139]

Gah but then you have to bugger around with complex toolchains, IDEs, ST's HID thing, all that stuff and then spend ages reading about it and working it all out. That is waaaaaay too close to the day job.

My entire toolchain for AVR is stolen from the ass of Arduino package as it's nicely compiled in there and dumped unceremoniously in c:\dev\avr and added to path.

Then the build script is (sod makefiles for this):

Code: [Select]

@echo off
avr-gcc -c main.c -Os -mmcu=atmega88p -DF_CPU=1000000UL
avr-gcc -mmcu=atmega88p -o main.elf main.o
avr-objcopy -j .text -j .data -O ihex main.elf main.hex

Program

Code: [Select]

@echo off
avrdude -c usbasp -p m88p -C \dev\avr\etc\avrdude.conf -u -U flash:w:main.hex

Flash a damn LED:

Code: [Select]

#include <avr/io.h>
#include <util/delay.h>

int main()
{
DDRC = 0xFF;
while (1)
{
PORTC |= (1 << PC0);
_delay_ms(500);
PORTC &= ~(1 << PC0);
_delay_ms(500);
}
}

And that's it. Hardly any work for me. Which is how I want it. Debugger? Got an LED - that will do!

[beanflying]

So; just goes to show you: you CAN do something USEFUL with a 3D Printer; it's not just about making little obscene gestures and things with boobies out of plastic! 

It's all about the electronics.

https://youtu.be/UJGe3Onw5Fo

Edit  - No Micros, Code or other such junk was used in the tronics - pure 4017 driven by a 555 

[med6753]

Hey... I tripped over this today and immediately thought of you and Med's MANY discussions on "bosses" and "employment" in general... 

mnem

What is this "bosses" and "employment" that you speak of? I have no idea what you are talking about. 

[mnementh]

@bean, @med: 

mnem
"Fair dinkum..." I think is the term here... 

[mnementh]

Gah but then you have to bugger around with complex toolchains, IDEs, ST's HID thing, all that stuff and then spend ages reading about it and working it all out. That is waaaaaay too close to the day job.

My entire toolchain for AVR is stolen from the ass of Arduino package as it's nicely compiled in there and dumped unceremoniously in c:\dev\avr and added to path.

Then the build script is (sod makefiles for this):
(SNIP)
And that's it. Hardly any work for me. Which is how I want it. Debugger? Got an LED - that will do!

So, then there ARE things you hate more than Ardu... and we've named two of them. You just don't know good when you've got it!!! 

mnem
Yeah, most of Ardu is still pants... but some parts are at least a nice, well-worn pair of blue-jeans. 

[beanflying]

I swapped to using the 32U4 based boards a while ago when I needed a small form factor. No external USB chip needed and Windoze 10 auto installs it. Yes I have blown up a VReg on one too  Not the cheapest option but it gets the parts count down.

Given I go far enough back to remember punching a hex keypad on a 6800 micro Arduinos Rock by comparison 

Pushing 30C and it's not 10am yet 

[tggzzz]

Given I go far enough back to remember punching a hex keypad on a 6800 micro Arduinos Rock by comparison 

The first computer I bought for an employer was a https://en.wikipedia.org/wiki/Acorn_System_1 which enabled a proof-of-concept demo in 3 weeks rather than the expected 6 months.

The first computer I used had 39-bit words, and a working example is now to be found in The National Museum of Computing, along with the world's oldest operating computer. Memo to self: get some test equipment with dekatrons in it.

[mnementh]

Do they have all the mainstream libraries ported over yet? When I last looked into them, they were new and half the libraries were still on the "to do" list.

Alternately, have y'all seen this: http://www.stm32duino.com/

https://www.banggood.com/STM32F103C8T6-Small-System-Board-Microcontroller-STM32-ARM-Core-Board-For-Arduino-p-1058299.html

https://youtu.be/EaZuKRSvwdo

And here's good ol' GS proselytizing the virtues thereof.

mnem
I'm going to feed the children now... not sure who I'm going to feed them to.

[malagas_on_fire]

And here is the NXP LPC2103 Zero Board alternative that stumbled some years ago, with JTAG normal and mini :

https://malagas.wordpress.com/2011/12/30/zero-lpc2103-board-exploration/