u/Octrockville

I'm ordering a few of these empty books (12 slot versions) and want to buy a roll of thermal paper labels but I want to make sure I get some that will fit. I plan on sliding the labels into the slot along with the component tape.

Any one have these they can measure?

Thank you!

I need to make a specific shaped pad and want a simple way to control the line segment lengths. Is that possible? I tried to change my grid spacing to a custom one (1.933mm), but that didn't work. Maybe it's too precise. Even if it did work, that is incredibly tedious because I would have to make custom grids for each segment anytime I want to make precise shaped pads.

I know I can use a different program like Fusion360 to make an SVG, but that seems really dumb. Like the solution for the program is to use a different program...

It would be great if I could click on a line segment and in properties it would tell me the start and end coordinates as well as the angle and length, all editable.

I am going to be hand soldering this LDO for a project: AP7383-33Y-13 (SOT-89 package)
Data Sheet
Diodes Inc. SOT89 Package Info

I was looking for footprints in KiCad and only see two SOT-89 footprints available. I was going to choose this but wanted to double check the footprint from Diodes Inc. and I saw that it's different. How can an SOT-89 footprint be different like this across manufacturers? I'm a newbie with this so I would love to know.

If you can see the picture, X2 in the PDF says 1.933mm but in KiCad that measurement is 1.721mm. All the other dimensions are off as well. Some larger and some smaller than the PDF.

Am I better off making a footprint that matches Diodes Inc.'s specs exactly? Has anyone used this component before?

I am using the L78L05ACD13TR for my project. I have a +12V source and this will output +5V to power an ATTiny85, SHT41 humidity sensor breakout board and an LED indicator. So the current draw will be pretty low (I think under 20mA). I have been doing research and found people saying that the 78XX family needs special attention to capacitor selection of type and value, like ceramic vs electrolytic.

Admittedly with the help of chatgpt I have chosen larger ceramic capacitors than the data sheet recommended for it's test circuit, but would like help from actual experts.

The +12V source will be super close, like 2cm away, so distance isn't really a factor I don't think.

The datasheet (here) doesn't say anything or give any warning about selecting caps other than what is shown in their diagram.

I hope I'm over thinking this, but I just know there's so much more to understand about this kind of thing than I currently know.

I made some adjustments based on what others have said and wanted to get some final feedback. I appreciate the help!

My last design didn't have the voltage regulator but I realized that I actually do need one. I wrongly thought the housing this was going into already had a 5V output. I also removed the ICSP pins because I'll be using an 8 pin dip socket for the attiny.

The last picture is the SHT41 breakout board that I will be using and it'll hang off the board near a vented area of the housing.

I posted recently (here) with the original and made some tweaks that were suggested. Such as adding a the 10kΩ R1 resistor and moving C1 and C2 caps closer to the ATTiny. I also organized the traces a bit better to reduce the islands in the copper pours I had. Would love a once over to make sure I'm on the right track.

Thanks!

So clearly I'm a beginner but hoping someone can still give this a quick once over to see if there are any glaring problems.

My existing fan PCB stopped working so I wanted to make a simpler version that I can pop in. It will use the same +12V and +5V power that are still there and drive the fan that is still functioning. The PCB will be the same size with the Molex picoblade connectors in the same spot so it can be a drop in replacement using the same mounting clips in the fan housing.

I will be using a SHT41 sensor on a breakout board you can buy on amazon. That will overhang off the right end of the PCB to be closer to a little vent in the fan housing so it can sample the air better.

The actual fan is working, but the control system is messed up. It just turns the fan on and off in a constant random pattern. I am trying to fix this but haven't had luck yet. In the mean time, I'm thinking of replacing the guts with my own simpler version that drives the existing fan based of an arduino and humidity sensor

I'm a novice with electronics but have made some fun projects using KiCAD and ordering my own custom PCBs.

The current fan control system (when it worked) had a lot of settings and options but I would make it much simpler. Just one fan speed, one humidity level and maybe a 5 minute timer once it gets below the humidity threshold.

Could anyone help with identifying what the boards in the pictures are likely for and which I would be replacing?

In image A, I'm not sure what the left PCB is for but it looks like the right PCB is the humidity sensing board with the humidity sensor itself hanging off the right side. Image B seems to be a 240v step down board with an ON/OFF switch with two JST connectors that bring power to the two PCBs in image A.

I feel I would keep the 240v step down board but maybe replace the two other boards?

I have a little project that will be running off two AAA batteries and I want to keep the current draw low. This LED will just be an indicator that is sometimes on and doesn't have to be bright (it will also be behind a 3D printed diffuser). It's easier to solder the 3mm hobby LED but the SMD LEDs might be more efficient. Does it matter or am I just better off going with the 3mm LEDs? They are cheap and simple to solder and replace if needed.

I'm a beginner so I need to remove and test my code very often. It gets annoying using a breadboard so I made this little piggyback board to go on my arduino uno knockoff. Do I really have to unplug the USB cable from my computer to power down the arduino or can I just flip the lever on the ZIF connector and remove the attiny while the uno is still powered up?

I'm sure it's best practice to unplug the USB cable but I'm curious what you all do. Play it safe? I read that these attiny's are quite robust.

Apparently I have been using an outdated core by David Mellis and it's recommended to use the core by Spence Konde / Drazzy (I read those are the same thing?) I am on Mac and went to "Preferences > Additional boards manager URLs:" and typed in "http://drazzy.com/package\_drazzy.com\_index.json". When I search for ATTINY in the Boards Manager I see a list of possible ones to download and install but I am getting an error when trying to install ATTinyCore by Spence Konde.

Can someone help? I'm very new and don't think I have ever installed cores before. Like I don't remember installing the David Mellis one so maybe it was included or something?

Also the air bladder in the tank had no pressure so I brought that back up to what the manual states (1.5 bar).

Lastly, the pressure gauge reads 1 bar even when the pump is off and there's no pressure and all lines are disconnected.

I'm hoping the pressure switch is the main issue but I guess the gauge is also bad?

Any advice is appreciated, never opened up a pressure switch in one of these pumps before.