This was another great project from you, very much appreciated, many thanks!

Hello Louis, thank you for making the boards available , I have put my order in on e-Bay,I didn't fancy going out in the cold workshop to make them. 73 Paul M0BSW

As always a pleasure to follow you because I'm learning something new in every video

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks for the comment. Regards, Louis

Thanks Louis for your generous help. I have added an LED to indicate the output is on.

Great channel and like the flow from idea stage to build to mods :)

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks for your comment.

Fantastic update! This looks to be a great bit of kit to add to the bench.

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks for the comment. Regards, Louis

The PCB's are first class, Saved me a lot of time and way better than I could produce in my humble workshop lol

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks Brian.

Another great electronic, project...great DMM (Fluke 87V) too.

Hello Louis hope you are well, I've had a bit of success with programming arduino's, I took one of my blank nano's put the calibrator program on and one library file at a time checking for any errors at every stage, my god it worked first time, now the door has unlocked I'm going back to revisit all of your other projects , I always get there in the end, life in the old 64 Year old yet, it's opens the door for the Electronic load is definitely on the table now.

Thanks, specially for the li-ion battery solution. I saved me a lot of time searching for a solution that I could understand.

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks for your comment. Regards, Louis

Thanks for your work and sharing it.

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks.

Hi Louis, I really like the projects you've explained on your channel. It's great to be able to build useful tools while learning some electronics. And you do such a good job of explaining the design and operation. I hope you will be "back on the air" sometime. About this project: At about 6:42 in the video, you explain that the resolution above 4V is only 2mV and above 8V it drops to 4mV. Correct me if I'm wrong, but doesn't that mean that you cannot set a voltage down to 1mV accuracy for these ranges (although the UI allows you to do so)? For example, if you request 4.001V, the calibrator will actually try to generate 4.000V, due to rounding. That might lead a beginner to think they have a calibration error. Maybe it would be a good idea to show the actual (rounded) voltage that the calibrator is trying to output in these cases. Thanks for sharing your knowledge and love of electronics.

What a big contribution to Arduino hobbists, cheers from Colombia, hope you´ll continue doing so. Gustavo

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks Gustavo.

Very nice job Louis. Thanks for all your hard work.............................................Berni

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks Berni.

Surprised how well homemade device works... Nice project..

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks for the comment.

As always a great explanation and fun project.

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks for the comment.

A really great idea to sell the PCB's on ebay. That makes it very easy for us who are not custom to make PCB's.

@scullcomhobbyelectronics1702

6 жыл бұрын

This is the first time I have sold anything on eBay so was not sure just how it all works, but hopefully I got it correct. If my viewers on You Tube find this idea of making PCB's available on eBay then I will do it for some of my other projects. I had these PCB's made in China but used DHL for fast track delivery which only took 3 days (if you use normal post delivery from China it takes a several months to arrive) but I also had to pay custom duties and DHL Admin fees on the total value including delivery costs, which added to the final cost, but they were still cheaper than getting them made in the UK. Regards, Louis

I like Kicad, I guess you do to, its improved a lot since you made this great vid...cheers.

Excellent explanation. Thanks.

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks Paul. Regards, Louis

Power supply circuit is finished, I hope I get the last missing parts on Monday :) Great design, love the battery power supply circuit which is very universal.

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks Michael.

Hi All, Thanks Louis for another Great project. Just finished putting mine together and all works great up to 8v, however anything over 8v and up to 10v only gives me around 8v . Im using a Keysight U1272A auto ranging DMM. I did use 16v Tantalum Caps for C2 and C14 but have since changed those to the Required 25V tantalum Caps. after I changed these I got 10V but then it collapsed back to the 8V. Any Suggestions would be greatly appreciated from anyone. Thanks for all your great Projects

Great project; Thumbs up. The only complaint is the slow refresh on the display. Waiting for the switch from one screen to the next is painful. Suggest a different screen -faster refresh, or larger so that all functions are displayed on one screen.

thanks for the good stuff man

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks Lord.

Just Received my Voltage Calibrator PCB´s. Very good quality indeed!!. If you find the time to get PCB´s produced for some of your other great projects, I will certainly be interested. And seeing how many subscribers you have and how fast your first batch of PCB´s were sold on Ebay, I think it is safe to say that you will be selling :-) And as an added bonus, your PCB´s are cheaper and ships way faster than OSH Park.

@scullcomhobbyelectronics1702

6 жыл бұрын

Glad to hear. Yes I will look at making some PCB's available for some of my earlier projects. I am currently working on a single double sided PCB for the Electronic DC Load and testing a proto type of this PCB at the moment. I will put some on eBay once they are fully tested. If there is an interest I will also make PCB's for some of my earlier projects. Maybe do a video update on PCB's when available. Regards, Louis

you sold out of boards in three days?! very good! gonna have to make one! Thanks for all your hard work!

@scullcomhobbyelectronics1702

6 жыл бұрын

I have some more on order and should have them in about 4 days as I have paid for DHL delivery. I will put them on eBay again when available and give the new eBay link in my comments under the video. Regards, Louis

Thank you for a great project. I got the screen in today, and it all works perfectly, I have not calibrated it yet but will be doing it soon. The idea of software calibrating it really intrigues me. So I hope you will find the time to do a follow up video? Thank you again from Norway.

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks martin for your comment. Glad to hear it all worked OK. I may do a followup later. I am just working on a new PCB for the DC Load project at the moment. Regards, Louis

Thanks again for posting. As usual a great video. I have ordered some PCB's from ebay.

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks Christian. I thought I recognized your name on the order for the PCB's. I posted them earlier today. As you placed two separate orders you paid a little to much for the standard postage. So I used the extra money to send your package special delivery with tracking, so hopefully you should get it quicker. Regards, Louis

@cccyberfamilydk

6 жыл бұрын

I am looking forward to receive my package. :)

@cccyberfamilydk

6 жыл бұрын

Hi Louis. The package arrived today. Just in time for the weekend. :)

@scullcomhobbyelectronics1702

6 жыл бұрын

Glad to hear that was quick you must have a good postal service in Denmark. Regards, Louis

Nice project just ordered the pcbs cheers OE1MIS thank you for sharing

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks. I sent out some PCB's today.

@TheRcEngineer

6 жыл бұрын

Scullcom Hobby Electronics Thank you but here was no need to hurry. I am an embedded systems developer if in future you need some coding help count me in. Cheers Michael

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks Michael for the offer. Just to be clear are you in Austria if so I have just sent you a message in eBay with my email address. Regards, Louis

@TheRcEngineer

6 жыл бұрын

Scullcom Hobby Electronics yeah that’s me for Vienna/Austria :)

Thanks to Louis for the caps i needed ive now just finished assembling my boards, No case yet but ive got one on the way. I do have an issue with my display in that the touch does not work, Made all the usual checks and thinking i may have the wrong display marked KMRTM28028-SPI . its the 2.8" touch screen

@scullcomhobbyelectronics1702

6 жыл бұрын

Hi Brian, The correct type of display should be a TJCTM24028-SPI which is the one I used. www.ebay.co.uk/itm/2-8-240x320-SPI-TFT-LCD-Touch-Panel-Serial-Port-Module-PCB-ILI9341-5V-3-3V-Red/401332638377?epid=908253714&hash=item5d714a12a9:g:2GkAAOSwurZZI8~9 Make sure you look at the photos to check the number printed on the PCB before buying. The KMRTM28028-SPI which you have is know to have a bad touchscreen. If you email me I will try and help you. Regards, Louis

@G0WZB

6 жыл бұрын

Thanks Louis The one i ordered from ebay has the correct number in listing but what i received has a different one....look same but not. I've ordered another from the same supplier as yours and emailed them to double check im getting the same one and they said yes. Hopefully get that in a few days. Thanks so much for your help.

@scullcomhobbyelectronics1702

6 жыл бұрын

Hi Brian, The one they sent you was from an old batch with known issues. Let me know how you get on or if you need more help. Regards, Louis

@G0WZB

6 жыл бұрын

Correct screen arrived today and works as it should. Anyone else building this make sure you get the exact screen Louis used, My original one was listed with same part number but what i received looked the same but had differet part number and did not work, Easy mistake to make with some ebay sellers.

Good video.

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks Steven.

i love these improvements 🥳 and the new chips 🥰 also a great lecture voice 🐬🦚🍞🫖 is it possible to take two DACs and use one just for the unit values and the other DAC dedicated for only for the decimal numbers and control the output signal? 🤔 Errr...🤥 o my where is my bread-board? 😳

At 12:40 u11 looks like it has a slider bridge across pins 5 and 6, it might just be flux but you may want to check it.

@scullcomhobbyelectronics1702

6 жыл бұрын

Pins 5 and 6 of U11 are connected together and both go to ground, so this is OK. Regards, Louis

if you were using a mega arduino, with additional INA105 and DG303B it would be possible to increase the output voltage for example up to 100v DC ? , perhaps using an AD2712K to have a high precision reference of 10.0000 vDC?

Isn't all the circuitry for disconnecting the ground in the battery charging circuit kinda pointless since that battery module can charge while supplying power at the same time? We could use a 5V 2A direct to the battery protection module and power entire circuit through the boost converter all the time which would eliminate the need for the 7805, the cutout circuitry and the buck converter. The only catch might be the current supplied from the battery protection module may not be enough while dropping up to 1A for the battery I guess (assuming the battery is fully dead)

I've just about finished the DC voltage calibrator,the only difficulty I have had was those blasted leads,I bought the crimper had ago,but finally gave up fine tip on the iron and soldered the wires in the connectors all working fine , a blind man would never noticed that there soldered in instead of crimped, although I will have to learn the crimping process,I have used all vishay, Texas chips military grade resistors,1 vishay resistor ,rubycon capacitors,and the ceramic I forgotten who makes them, so it has cost me more than if I made it normally The reason for using expensive components,is I want to see how it works out on the final calibration & results

@scullcomhobbyelectronics1702

6 жыл бұрын

Hi Paul, Yes agree those small JST-XH connectors can be a pain to grimp the leads, the connector lugs are so small. Using a crimping tool is also not that easy and takes a lot of practice. So like you at times I also end up soldering them to ensure I have a good connection. Looks like you have gone to town with ordering good quality components, which are always more expensive. Hope the results of your efforts work out well. Regards, Louis

@paulcollins664

6 жыл бұрын

Hi Louis , I hope so to, I've been giving the idea of using good components for some time, Your DC voltage calibrator was the chosen project, it will be of great use to me, so she got the treatment, I hope TFT colour screens will feature again in future projects you have in mind. Regards, Paul

does the 1uF 25v tant matter if it is a 35v item, thanks Louis

excellent

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks. Regards, Louis

ur welcome man

Beware of the XL6009 modules - they are only specified for 5v minimum input - I built my version of your voltage source (but with an oled 128x32 display and numeric keypad) and have bene having issues with the battery module. I've pulled out the up converter and run it through on my bench suppy with a load and discovered below 5v expect output voltage to be all over the place. On power up theres an inrush of about 1.5A! and at voltages below 4.2/4.3 the output voltage is around 12v which of course messes up the 15v and -15v supply for the op amps and in turn means the 5v supply is also problematic. Trying to source an LM2577 based module as they at least are rated for 3.5V and up.

Hi nice video and project. 2 comments Why did you not do the PCB layout to take advantage of the standoffs in the case bottom. I personally would have had a battery disconnect operation either by using another switch or a DPDT centre off power switch for power on + charge, off, charge only. So that the the battery is not being permanantly discharged by the 19V up converter when the DC input plug is not connected.

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks for the comments. The reason I did not take advantage of the case standoffs on the PCB is that I did not want a PCB design suitable for one type of case. So I kept the fixing at the edges of the PCB and used nylon standoffs. If also made the PCB layout easier to do. I take your point about using a DPDT that is an option. The drain of the battery by the DC-DC converting is quite low. Regards, Louis

The Ebay page is missing!

Mines built now bar the charger unit and battery. However i have an odd problem with the touch screen. display is all fine but the button presses are diagonally mirrored? ie set voltage bottom left button touch position is upper right corner help

I have the unit all built now a software program problem,having never anything to do with arduino, I'm stuck good and proper,this is the problem all the buttons come up on the screen, but none of them work,

Hello.The screen update is a Little slow. May I suggest to use an ARM M3 core that run at ~ 70MHz or better.Test the display with the Cypress Pioneer kit or similar first. Or maybe use ARM cpu in the next project with TFT-Display.Anyway. Great project.

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks for your comment. Yes agree it is a little slow but that is due to the Arduino library for this type of display. I understand that there may be some faster Arduino libraries for this type of display and that may be worth trying. I agree with you an ARM M3 would be faster and may also be another option. Regards, Louis

I see a capacitor across the output leads. Unless I missed it somewhere, I see no mention of it. Can you provide the value please? Great project BTW! Mine turned out great.

@ivolol

3 жыл бұрын

Near the end of the 2nd video, talking about output noise

@ChartRecordsFan

3 жыл бұрын

@@ivolol I found it, thanks! It's .22 uf cap.

It seems that with your KiCad files you may have created custom component outlines for your modules etc, so when attempting to open these files one gets an error message and the .sch files have blank spaces filled with ”?” Please, Are you able to include these component outlines as shared components so that they may be “imported” into the local library and the .sch to display correctly?

@scullcomhobbyelectronics1702

6 жыл бұрын

Hi Bruce, When I checked them they did seem to work OK. In the KiCad zip files I provided, I did include my library file for each board (for the main PCB there were 2 library files) - look for the ".............cache.lib" files for each board in the zip files. When you open the main PCB KiCad file, if a box pops up saying "The following libraries were not found" just click on "Close" on that box and it should work OK. If you have problems you may have to add these ".............cache.lib" manually. The 4 library files in question are listed below: TFT_selectable_voltage_Ref-cashe.lib TFT_selectable_voltage_Ref-rescue.lib DC_Cal_TFT_Arduino_Module-cache.lib DC_Calibrator_Battery_Module-cashe.lib Let me know how you get on and if this sorts out your issue. By the way I am using Version 4.0.7 of KiCad. Regards, Louis

Why didn't you also replace the 4.096v regulator with one of the self regulating ones? It looks like the MCP1501 does come in a 4.096v version.

@scullcomhobbyelectronics1702

6 жыл бұрын

The MAX6241 or MAX6341 already has excellent ±0.02% initial accuracy without the trim pot. So the variation would only be from 4.0968V to 4.0952V. In practice I have found it better than this. If you wish you can leave the trim pot out. On the schematic I mark it as "optional". Regards, Louis

Hi, Nice work. However I always feel an itch when I see a reference pin left floating..... in the battery option, I would suggest you connect the switch ground (IN -) of your DC-DC converter to its IN+ through a high value resistor (let's say 100 K or more). What do you think ?

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks David for your comments. The pin I used to test the reference volts is really meant for supplying the second DAC in the IC with the reference voltage so after you carried out the check you can simply plug a little shorting link across the two pins (of J3). In that way it is no longer left floating. The choice is yours. With regards your suggestion of a resistor across the output of the DC to DC converter. This should not be necessary as there is already a resistance across the output made up of the full resistance of the trimpot and a resistor going from its bottom end to ground. One possible enhancement could be to replace the output electrolytic with one with a lower ESR. Regards, Louis

@davidvb3754

6 жыл бұрын

Sorry, I didn't explain myself correctly. I was referring on the DC-DC up converter labelled M3 on the battery option. With the switched GND, the IN- is left open (I don't know the schematics of the module in itself, but I assume that IN- and OUT- are simply connected together). See schematics on 20:39. In that case, that's a ground signal left floating. Couldn't this lead to unexpected behaviour of the module ? Therefore my suggestion to add a high value resistor between the inputs

@scullcomhobbyelectronics1702

6 жыл бұрын

OK David I see your point now. I have had no trouble up to now and all works fine. But I will take on board your suggestion in the event of any issues. Regards, Louis

I'm not overly happy with the quality of the trimpots on the chinese modules, had some negative experiences with long term stability. I usually replace them with real Bourns trimpots or fixed 1% resistors.

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks Roland for your comment. Yes I agree the trimpots on these Chinese DC to DC converters are not as good as the real Bourns trimpots. However, in this application any slight drift in voltage setting is not an issue as it it not to critical. Regards, Louis

May I ask why you don't use the MCP4822 with internal vRef? accuracy?

@scullcomhobbyelectronics1702

6 жыл бұрын

I did look at the MCP4822 initially but the internal VRef accuracy is not good enough for this project, since it can vary by about 2% also the internal VRef noise is quite high at 290uV peak to peak, plus the temperature coefficient is typically 125ppm/°C and can be as high as 325ppm/°C. Whereas the MAX6241 has an accuracy of 0.02% and a very low noise level of 1.5uVp-p, also its temperature coefficient is typically 1ppm/°C but no higher than 8ppm/°C absolute maximum. The MAX6341 alternative is even better but twice the price. As we are trying to make an accurate and stable programmable voltage reference source the best option is external voltage references. I hope that helps. Regards, Louis

Could you make a PCB from the previous project?That would be awesome. Thanks again for your excellent work.

@scullcomhobbyelectronics1702

6 жыл бұрын

Hi, Do you mean for my previous version of this project which I showed in Part 2 where I used a LM4140C for the 1.024V reference with adjustment - or do you mean for my other projects I have done such as Electronic DC Load, Millivolt Meter, Milliohm Meter, GPS Locked Frequency Reference, Function Generator etc? Could you clarify please. Regards, Louis

@recolaq

6 жыл бұрын

Hi Louis, Sorry for being unclear. I meant the last version of the Electronic DC load project. I have tried to make parts of that project on a piece of perfboard, but that didn't work out to well. I guess there are more enthusiasts for a PCB.

@scullcomhobbyelectronics1702

6 жыл бұрын

I have already designed a single board double sided print PCB for the Electronic DC Load and am testing it as we speak. I plan to then give an update and make the PCB available on eBay if anyone is interested. The size of the PCB is 134mm x 137.5mm. All the components even the SMD IC's are now on top of the PCB. The cost of the PCB is likely to be around £12 plus P & P. Hope to provide an update soon. Regards, Louis

@recolaq

6 жыл бұрын

That is very good news.I will definitely order one and give the project a restart. Thanks Louis

Hi, I'm looking for help with this project. I made DC voltage calibrator. I bought the original PCBs on ebay. I have a problem with the display. I have already bought a 2.8" display. The display works, but the touch doesn't work. I thought the display was broken and I bought a second one, but I made a mistake and bought a 2.4". With this, everything works. I bought two more 2.8" displays again but the touch absolutely doesn't work on these. I can't understand why the 2.8" doesn't work, while the 2.4" does. Can you help me?

will you be making the PCBs available again Louis?

@scullcomhobbyelectronics1702

6 жыл бұрын

Hi Mick, I have a new batch of DC Load PCB's coming later today or tomorrow. If you wish I will reserve one for you. If you post a message on my website www.scullcom.uk that will then allow me to send you an email so I can arrange delivery to you. When you post a message on my website I will be the only person who can see your email address, so its kept private. Regards, Louis

I have a different display. What part of the software do I need to change or is it futile?

@scullcomhobbyelectronics1702

6 жыл бұрын

Hi Rudy, There are some variations of the 2.8 TFT SPI display sold on eBay. The one I used had the following details printed on the back of the display PCB "TJCTM24028-SPI" If you have a different variation of this display then that number may be missing and you may find the touch screen element may be configured in reverse. Therefore, the active touch screen element of your TFT display may be the wrong orientation (180 degrees out) so effectively the touch screen part is upside down. You can easily correct for this by changing one line in my Arduino code to instruct the TFT display to rotate the display by 180 degree to match. It should then work OK but you then need to rotate the display PCB module by 180 degree before you mount it in the project case. In other words you need to mount the display module upside down!! If you look at my Arduino code for this project - look for the following line of code in the Programme Set-up Routines: tft.setRotation(1); //we translate the display into landscape orientation Then simply change that line of the code to read as follows: tft.setRotation(3); //we translate the display into landscape orientation (rotate display 180 degree) The number in the brackets alters the Screen Display Rotation as follows: 1 = normal no rotation landscape orientation 2 = 90 degree rotation portrait orientation 3 = 180 degree rotation (upside down) landscape orientation Kind regards, Louis

I have a 3.5" display made by mcufriend.com. Is there any reason it wouldn't work?Of course i'll modify the code accordingly.

Thanks for sharing your great work! It seems, that there is a missing "m" in "www.scullcom.co/DC_Calibrator_main_PCB_KiCad_files.zip" otherwise your server were hosted in columbia :) Again many thanks, I've learned a lot from your channel!

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks Reb. I have just corrected the link error, so it works OK now. Regards, Louis

Those PCBs are selling like hot cakes on ebay!

@scullcomhobbyelectronics1702

6 жыл бұрын

Yes I am pleasantly surprised myself. This is my first attempt at selling on eBay and it took me a while to work it out. Regards, Louis

@Drew-Dastardly

6 жыл бұрын

You had sold most of them and had 10 left with 28 days to go when I made my comment earlier, you now still have 28 days to go and only have 3 left and all in less than 24 hours! I'm holding out for the LM399 or dare I say the LTZ1000 version ;) ETA: I just checked after my silly post and there is only 1 PCB left now! Welcome to selling on ebay Louis. It's great, but just wait for the complaints from the great unwashed to come in when they feck up their soldering, etc. and then blame you for it! Then the massive ebay/paypal and postal fees which I'm sure you have costed in as a perfect seller not expecting any returns. (BTW: I seriously doubt this will be an issue here, though it is normally a wasted cost for other ebay items)

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks Drew, I have just ordered another batch of 25. The LM399 would be a nice option but I think the LTZ1000 is far to expensive for the hobbyist. Anyway I will be working on new ideas for my videos so you never know. Regards, Louis

Thee pcb's sold out rather quickly. Are there any plans for a second run? Also pcb's for the electronic DC load would be nice. Love your videos.

@scullcomhobbyelectronics1702

6 жыл бұрын

Yes I was surprised how quick they sold. I have just ordered another batch and should have them soon. I have also redesigned the DC Load as a double sided PCB and am testing a few at the moment. If you want to give me a call in Private Messages here on You Tube I may be able to help with some PCB's. Regards, Louis

@PeachState112

6 жыл бұрын

Scullcom Hobby Electronics I don't see the option to send a private message in your about tab. I live in the US so I expect higher postage but I am interested in the boat show for both projects. Thanks, Matt

@PeachState112

6 жыл бұрын

*boards*

@scullcomhobbyelectronics1702

6 жыл бұрын

To send private messages: This only works on a PC with a normal internet browser (not a table or phone) Go to the channel of the person that you want to contact. You can do this by clicking their channel name underneath one of their videos. Click the About tab. On the righthand side of the screen under the Views figure (Views 970,000) you will see a light grey flag and a light grey speech square. Click on the speech square bubble and then a pop up comes up to send a message.

@cccyberfamilydk

6 жыл бұрын

I would love to buy PCB for the DC Load.

Hi Louis, do you have any more PCBs for this project?

@scullcomhobbyelectronics1702

6 жыл бұрын

Hi, I do have a few spare PCB's left. If you let me have your email address I will contact you to arrange delivery. Alternatively, if you leave a comment on my www.scullcom.uk website I will be able to contact you via email. Regards, Louis

@scullcomhobbyelectronics1702

6 жыл бұрын

Hi Martin, I have sent you an email with details. Regards, Louis

pcb’s on ebay are “no longer available”. Any more in the works?

@scullcomhobbyelectronics1702

6 жыл бұрын

Hi, I do still have a few available. If you send me your email address in Private Messages here on my KZread channel I will contact you with details. Alternatively, if you post a comment on my website www.scullcom.uk i will also be able to contact you by email. Regards, Louis

@irgski

6 жыл бұрын

Scullcom Hobby Electronics Hi Louis, did you get my email? eebigdog2@gmail.com

@scullcomhobbyelectronics1702

6 жыл бұрын

Hi Grant, I have sent you an email with details. Regards, Louis

Do you have the boards?

@scullcomhobbyelectronics1702

6 жыл бұрын

Hi Rudy, Yes I do have a few spare PCB's if you require a set. Regards, Louis

Hello! Do you still have PCB on eBay? Could not find your email, have a few questions.

@scullcomhobbyelectronics1702

2 жыл бұрын

Hi, If you let me have your email address I will try and help with regards PCBs. Regards, Louis

@saulius659

Жыл бұрын

@@scullcomhobbyelectronics1702 Thank you very much! Here I uploaded: kzread.info/dash/bejne/k2Vt2bKxo9jRhrQ.html

Given the laboriously slow update rate on the display, one change I would seriously consider is using one of the STM32 F1 based "blue pill" ARM cortex micro-controller boards. They have a slightly larger footprint than the Nano but are supported in the Arduino IDE by the addition of some files available on Github. github.com/rogerclarkmelbourne/Arduino_STM32 Clocked at 72MHz you would hopefully get a blisteringly fast update on your display. Admittedly there is the learning curve of using the new platform but I think it would be worth considering. I personally have moved away from using the Arduino IDE myself and I now use the Atom Editor with the PlatformIO plugin as this allows development on AVR and ARM (and also PIC32.) I also couldn't help noticing you've taken up baking as those PCB's have sold like the proverbial "hot cakes" ;)

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks Nick for your comments. I have not played with the STM32 yet but I agree the Arduino can be slow. However, the main issue with the TFT screen refresh rate is the Arduino TFT Library, it needs to be improved. I believe someone on the internet has already improved the speed. I will have to do more research. Regards, Louis

6 жыл бұрын

I *think* the main reason of the slow display refresh is the used Arduino libs. Surely some implement a much better one, after all Arduino stuffs in general are mainly about a comfortable way not to use only an AVR MCU and code in plain C (no Arduino libs etc, which in most cases are quite slow, just search for videos in topics like digitalwrite is how much slower than the AVR MCU actually can do - even if you put something a port bit flip into your C code for that instead of digitalwrite, and it was just a simple example for these issues) or even better in assembly. And no, it's not a critic or anything "too negative against" Arduino, actually I like the "comfortable" solution as well quite often - though not always, that's true. Just using a stronger hardware may be a solution but it feels then a bit awkward, as the true problem is the software being slow. Nah, okey, enough from my bad English and long messages :)

You compromised a lot when you decided to go with I2C ports on the display. Use parallel data ports. I2C is good for detecting the touch part. Not to transfer data to the screen. This is painful to watch, let alone operate. Output ORing as you did with the up-inverter, without a back-flow protection diode, is something I haven't seen before! Did you measure for current leakage when plugged in? Nice project though.

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks for your comments. The TFT Screen refresh is a little slow but this may be rectified by using a different TFT Arduino Library - the Adafruit ILI9341 could be improved. I will do some further research. The good thing is that all software updates can be added at a later stage without the need for hardware changes. Regards, Louis

@pirateman1966

6 жыл бұрын

I though this TFT has option for parallel data loading. like these; www.adafruit.com/product/1770 Its strictly an SPI module. Although ILI9341 can be accessed via its 8-/9-/16-/18-bit MCU 8080-II series parallel interface scheme. Adafruit brought out these lines on their version. Still, SPI should be fast enough. I'll be interested to see which library you go with, as I have one of these exact TFT displays collecting dust. If it's as slow as this one, I might as well throw it out now and don't waste my time on a disappointment. Also, 10K interface resistors in your DC_Calibrator_schematics file are too big. 1K would be better for SCLK and DATA lines of the SPI from the Arduino nano, and still provide only 5mA@5V in worst case. Which can be tolerated by any pins on the Arduino. Looking forward to your next update.

I missed getting the PCBs for this project. If you make more please let me know. I’ll send you an email with my details.

@scullcomhobbyelectronics1702

6 жыл бұрын

Hi Michael, I have sent the details. Regards, Louis

For display, i suggest you use nextion HMI. nextion.itead.cc/ . only variable data send via rs232, it's no need uC power to run display!

Hello Scullcom Hobby Electronics, I sent you a message in KZread where I suggest some Important Electronics Projects, so you can check the received messages in your channel on KZread, thank you

@scullcomhobbyelectronics1702

6 жыл бұрын

Thanks Ayman I have had a look at your list. Regards, Louis

@aymanmoussaoui1221

6 жыл бұрын

The projects that I really want to watch on your channel are, The High Frequency Function Generator with the Maxim MAX038, The Programmable Lab Power Supply 30Vdc 5A or 50Vdc 5A and The Symmetric Adjustable Lab Power Supply +/- 30Vdc 5A, Because in fact these projects need time from Research and Experimentation. Thank you and Have a Nice Day.

Hello Louis, thank you for making the boards available , I have put my order in on e-Bay,I didn't fancy going out in the cold workshop to make them. 73 Paul M0BSW

@scullcomhobbyelectronics1702

6 жыл бұрын

Hi Paul, I have just packed your PCB's and will post them first thing tomorrow morning. Regards, Louis

@paulcollins664

6 жыл бұрын

Guess ,what I'll be up to this weekend Thank You Louis. 73 Paul M0BSW

@scullcomhobbyelectronics1702

6 жыл бұрын

Enjoy ;)

@paulcollins664

6 жыл бұрын

Hi Louis the package arrived today thank you so much, will help no end

@scullcomhobbyelectronics1702

6 жыл бұрын

Hi Paul, Glad to hear it arrived OK.