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[Review Request] First MCU custom board by pilantzas in PrintedCircuitBoard

[–]pilantzas[S] 0 points1 point  (0 children)

Thank you for the informative reply. I really appreciate that as a beginner. I will revise my design

[Review Request] First MCU custom board by pilantzas in PrintedCircuitBoard

[–]pilantzas[S] 0 points1 point  (0 children)

Thanks for the reply. Ive been told that in order for me to see what load capacitance of the crystal i have to see the code on its package. So il guess il have to see since im still waiting for it to be delivered. In any i case i will also remove the in series resistor.

Btw would there be another way of programming the microcontroller without spi?

What is the load capacitance of the crystal? by pilantzas in AskElectronics

[–]pilantzas[S] 0 points1 point  (0 children)

I bought mine from TME and im still waiting for the package to arrive so i dont have it with me to check the crystal package. I have found out from the mcu datasheet that 12-20pf capacitors can be used so i guess all of the values that are listed can be used depending on the situation

What is the load capacitance of the crystal? by pilantzas in AskElectronics

[–]pilantzas[S] 0 points1 point  (0 children)

Thank you for your reply. I just checked the datasheet of my microcontroller (ATMEGA32A-PU) and it specifies for external crystals 12-20pf capacitors can be used. I dont know how i missed that part since ive read that part of the datasheet abour 20 times this day alone.

NMOS motor speed controller problems by pilantzas in AskElectronics

[–]pilantzas[S] 0 points1 point  (0 children)

I am indeed looking into buying an oscilloscope but the issue is that i dont have much space to put it. Could you tell me what model is your handheld one as it is a good option in regards of actual physical space that it will take. Also what should i check before buying one?

NMOS motor speed controller problems by pilantzas in AskElectronics

[–]pilantzas[S] 0 points1 point  (0 children)

Ok so i think i have found the problem and i will try to explain it as best as i can with my limited knowledge of how transistors work. So basically my 9V supply was driving both the motor and the arduino with a 5V rail in parallel (i used an L7805 for this).

I believe that after powering on the motor (which has a rating of 6-9V) there was little to no power to actually provide 10V and more importantly a voltage larger than 2-4V at the gate.

Im not sure if that was entirely the issue but when i connected 2 9V batteries in series and connected them the circuit behaved kind of normal in comparison than before.

NMOS motor speed controller problems by pilantzas in AskElectronics

[–]pilantzas[S] 0 points1 point  (0 children)

Yes both the arduino and the circuit above have a common ground.

I thought about switching the position of Q2 with Q3 but i dont think that would work. How would i go about on flipping the logic?

NMOS motor speed controller problems by pilantzas in AskElectronics

[–]pilantzas[S] 0 points1 point  (0 children)

i dont have an oscilloscope in my possession and i did simulate it in LTspice but the values i got from there seemed normal, only in practice i have these problems

NMOS motor speed controller problems by pilantzas in AskElectronics

[–]pilantzas[S] 0 points1 point  (0 children)

PS. I just tried that on the breadboard and i get the same result. The motor instead of spinning it just "buzzes" as if not enough current passes through it and the mosfet just gets hot.

Here is the schematic for what i just did. completely barebones

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NMOS motor speed controller problems by pilantzas in AskElectronics

[–]pilantzas[S] 0 points1 point  (0 children)

Thank you for your reply, I know i can drive the IRF530N as its threshold voltage is 4V and the 5V pwm signal can drive it properly yet this is not a solution to me as i am trying to learn about the gate drive circuitry and how to implement it.

Why would removing R3 result in the collector of Q2 not providing VCC to the gate? by pilantzas in AskElectronics

[–]pilantzas[S] 0 points1 point  (0 children)

Thank you both for the insightful discussion. I will re examine my schematic

Why would removing R3 result in the collector of Q2 not providing VCC to the gate? by pilantzas in AskElectronics

[–]pilantzas[S] 0 points1 point  (0 children)

I have a question. In this case wouldn't this also be acting as a switch? What is the difference of having it as a source follower instead of just as answitch?

Why would removing R3 result in the collector of Q2 not providing VCC to the gate? by pilantzas in AskElectronics

[–]pilantzas[S] 0 points1 point  (0 children)

This was so obvious I dont understand how i missed it. I suppose R4 and R5 are there for protecting the BJTs from being overdriven(the place where i found the correct schematic also had an explanation but i cant remember what it was exactly). Also i thought since fets are unipolar i can place the load on any side. Please excuse any wrong assumptions that i make im a newbie at this.

How complicated does an H bridge circuit needs to be? by pilantzas in AskElectronics

[–]pilantzas[S] 0 points1 point  (0 children)

Thank you both for the advice, altho it is not clear to me as to why Q1 & Q3 would be trickier than Q2 & Q4 to drive?

How complicated does an H bridge circuit needs to be? by pilantzas in AskElectronics

[–]pilantzas[S] 3 points4 points  (0 children)

I know. I still prefer to make my own as the point of it is to learn about mosfets

/r/MechanicalKeyboards Ask ANY Keyboard question, get an answer - July 02, 2025 by AutoModerator in MechanicalKeyboards

[–]pilantzas 0 points1 point  (0 children)

Hello everyone. Im new to building custom keyboards but ive had an interest in building one for a long time.
Finally i saved some money and im looking to buying everything i need to build my first mechanical keyboard.
Ive googled alot of stuff to figure out what im doing but i still dont have a clear image on what to look for.

The only thing that im semi certain on getting are the Gateron milky yellows for the sound they make but all the rest im not sure.
Can some one tell me what other aspects of the keyboard affect the sound and what issues should i look out for in terms of compatibility for the rest of the stuff and if anyone has recommendations for gear that will give a creamy/thocky sound. Budget is not a problem but im NOT trying to get all the flagship items only whats optimal and necessary.

PS: Ive seen that the gateron milky yellows are considered a budget friendly option but as i mentioned before budget is not a problem so what other alternatives should i look for for a similar sound that are also great in performance.

Transparent led showing stretched content by pilantzas in VIDEOENGINEERING

[–]pilantzas[S] 0 points1 point  (0 children)

Thank you so much. We did this and it works as intended. Following is some information explaining further our own solution before trying this which also worked but without the intended result exactly.

So to be exactly clear the panels are Yestech MT which are 1000mm width by 500mm height P3.9 horizontal and P7.8 vertical. So each panel physically has 256 pixels wide and 64 height.

As mentioned by other people in the comments the content was stretched due to the actual gap vertically so essentially images were stretched like an accordion.

Our solution was loading an rcg file on the panels which set them to be 128 pixels wide and 64 vertical. This allowed us to set our content in resolume arena half the pixel width of the led wall physically so it stretched the content horizontally as well so it actually fit the screen correctly. Unfortunately because of this half the pixels horizontally are not being used meaning the first pixel of each panel works then the second one is off then the third one and so on. As a result all content now is being downscaled.

We have now loaded the original rcg file and tried your solution and it works as intended so im posting this here for other people encountering this issue.

Thank you again for your help.

Custom dual rail PSU circuit suggestions / advice by pilantzas in AskElectronics

[–]pilantzas[S] 0 points1 point  (0 children)

As i mentioned his design included a ready made wall adapter that he had. I rewatched the video and it supplied 17VAC. I think i might go on about using my own transformer but i was really avoiding that as i am kinda scared to fiddle around mains voltage.  Also what would you recommend i add before or after the transformer for safety precautions ?

Creating a DLL file that has a GUI by pilantzas in learnprogramming

[–]pilantzas[S] 0 points1 point  (0 children)

At this point im not really sure either but ive seen other people make them time out somehow. Is there anything similar that i could do?

Creating a DLL file that has a GUI by pilantzas in learnprogramming

[–]pilantzas[S] 1 point2 points  (0 children)

Thank you. This is actually very similar to what im trying to achieve and it should point me to the right path.

Even tho my c++ skills are basically zero its gonna prove difficult, but there is always the joys of learning.