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More Electronics, Projects And Tech Chat with Rich &
More Electronics, Projects And Tech Chat with Rich & Detlef
#Electronics #Projects #Tech #Chat #Rich
“Learn Electronics Repair”
It’s great to sit down with friends and talk Electronics. In this video Det and myself do just that once again. This is unedited video, almost like a live stream. Let us know what you think.
This video is sponsored by PCBWay For All Your PCB needs: free $5 discount…
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I was curious about the "SMT VERO" board in the thumbnail picture. I searched on PCBWAY website to no avail. Any info would be appreciated.
The milliohm meter is quite classy (scullcom hobby project) The INA106 Differential amp is a solid piece of kit probably expensive because Burr Brown semiconductors just are the OLED is almost optional because its just serial data. The LTC2400 chip is a 24 bit ADC and the ADR4550 is Ultra-Low-Noise, High-Accuracy 4.096V Voltage Reference. With these parts and a good design It will perform !! I hope you do build it because if two 741 opamp's can outperform it then I'll eat my hat. The second one looks fine too but its not in the same league as the first, and you say well they both work the same way but the first one is scary, …of course they do !! they work the same because you can't change OHM's Law and they both use it !!!!. The last bit of software is for Det and good luck debugging that 'IF' riddled malarky buddy LOL!……… you two are great !! and you did ask for opinions LOL!!! one last thing if you want an absolute definition of " Heath Robinson" its that project in the white box, veroboard and a transformer rattling about with hot glue holding it all together. LOL !…Must admit I loved this……..cheers boys !!!!!!!!!
I looked on pcbway and the guy does give you a .HEX file….cheers.
It's not a PTC guys it's an RTD. RTD (Resistance Temperature Detector) There is a lot of science inside hence the price. While both RTDs and PTC materials have a positive temperature coefficient, their roles and applications in a soldering iron are different. An iron with a C245 tip using an RTD sensor is primarily focused on accurate temperature measurement and controlled heating via a separate heating element and a controller. On the other hand, a soldering iron described as "PTC" would imply it uses a PTC heater for self-regulating heating, which is not the case with RTD-based systems.
Richard, do you think the sluggishness of the Electrolab meter would be improved by reducing the values of R14 and C8, perhaps by a factor of 10 on each? How would you feel about trying that out for us and seeing if you can speed up its settling time? I'm tempted to build one of these myself so perhaps I could tinker with those values and eventually report back.
The curious scientist milliohm meter is based on a design by Louis Scully on his skullcom website, that design is actually very well explained on some YT videos, some of the parts look expensive though.
Hi Richard.
Heath Robinson was a cartoonist and illustrator famous for drawings of impossibly complicated and humorous machines, made from unlikely materials. String was very popular, usually knotted.
The machines do look as though they would work, and have good engineering principles, although I believe HR was never trained as an engineer.
I built the milliohm meter project that you linked, it works very well.
Those 5-digit volt meters are extremely accurate, but are often delivered with a zero offset. In order to correct that offset, you need to connect the black and yellow wires together (so the terminals aren't floating) then apply power while shunting the two open vias on the board beside "I_ADJ_Z". The digits will spin then stop, you remove the shunt, and then have a perfect zero. Proceed to calibrate the voltage if necessary.
good tip with the kelvin probes i needed some for my Fluke 8520A
edit: at the 5 ohms max maybe you could add a zener diode on the input?
And now for something completely different…
ChatGPT had the latest iteration released (4o). Upload an image of the schematic and ask “ Chat” to give you an analysis of the circuit. Ask for input on errors and how to optimize .
If that’s not crazy enough, ask “Chat” to write code ( I asked for C-code) to make it function as it currently sits.
I just did it and was blow away that I received a response at all let alone the level of information I received.
I’m still learning so it could all be gibberish or somewhat viable info.
Thanks for the videos!!!
Also, you guys should make this a permanent setup. There is definite chemistry while bouncing ideas off each other, it’s highly entertaining. I hope Carlos gets back into the mix. The three of you were well on your way rivaling Monty Python!!
Thx,Guys!
I suppose one advantage the digital milliohm meter would have is easy addition of more features. Like beeping (with frequency determined by resistance), or data logging/exporting (e.g. putting the value on screen for YouTubers).
If you really wanted to build (and fix) the other meter (that blows its ADC), maybe some auto-ranging function could mitigate the problem. Start with a high potential divider, then have the MCU gradually switch to lower sensitivities once it has determined the resistance is within an acceptable range. But that would make the circuit even more complex, so I also favor the Ukranian meter.
It would be worth Det Googling(other search engines are available 😃) 'heath robinson pictures'
For the schematic 6:15 please read thread AxxSolder – JBC soldering controller on EEVblog's forum. Nowadays tips use series connected thermocouples embedded in the tip end for fast control loop response. LM358 ohms/temp readings are only valid at certain points on the chopped DC waveform.
RE: ATMega8
Pin 1 • INT1 – Port D, Bit 3
INT1, External Interrupt source 1: The PD3 pin can serve as an external interrupt source.
PC0 is an ADC pin. The opamp is an ohm meter. The pin 3 in the connector links the temp sensor of a wire heaater. The other irons are ptc. They are all controlled by on-off switching, basically PWM. The resistance is measired during the off time.
for the soldering controler project… why not add a switch for earth on / off ??? that is just a few cents
how about a butt warmer for the winter days ?? !!!
Great stuff guys.
My thought's about the soldering iron circuit. (take with a pinch of salt)
Perhaps the two/three types of tip are not the same, one could be PTC (The one you have) and the other could be just a resistive wound wire type.
As I mentioned you cant use PWM (Alter the voltage) on a PTC, it's happy temperature is set in the factory (set in stone to to speak) to regulate it you switch it off at the temperature you want it. (the circuit can do this) and it could be the one linked to pin 3 which it can read the feedback through the op-amp.
The circuit says PWM to drive the power, BUT PWM only if a resistive wound wire type is plugged in. You can control a resistive wound wire type with PWM.
Love the interactions between you two and the ideas and circuit descriptions – great learning info for hobbyist newbies like myself !
Heya, 😉 to master minds at work lol