Using extra wires might be more reasonable in a breadboard but I want to plan my circuits before they go on strip board and I generally want them to be as small as possible which couldn’t be the case if I don’t compact the circuit as much as possible. It’s rare that I make anything where size is not a concern. I doubt this feature will ever get looked at since development isn’t happening much but I wanted to submit the suggestion anyway.
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Different shades of grey for part legs
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Different shades of grey for part legs
This would be difficult to implement. There are a limited number of colors available and a vast combination of parts that would need different colors. The only way I can see making this work would be to be able to edit the color of a pin (which means changing the svg on the fly which isn’t currently possible AFAIK.) That said there is a project to redo fritizing as a web app in javascript and they may consider this when the project gets further along.
Peter
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Testing OP-amps
I have one of those cheap 0-30V 3A power supply kits that are known to blow TL081 op-amps, so I want a circuit to plug them in and test them.
I tried this one where a LED blinks if it’s good, but nothing happens.
https://circuitdigest.com/electronic-circuits/opamp-lm741-tester-circuit
My circuit - my SCH has pin 2 and 3 flipped.
Op-amp test.fzz (16.4 KB)
TL081 datasheet.
I did this test and 4V in makes out 7.3V with pin3 at 5V, which makes pin 2 read 5V.
Is this last test good enough for a blown op-amp if the voltages are the same as in the vid, because the 3 op-amp pass this test.
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25 hole Breadboard
Can the size of the breadboard be changed other than the drop down? I’m wanting to use one that is 25 holes. 5 by 5.
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Testing OP-amps
If you are getting 7V out with 4V in from the circuit in the video your op amp(s) would appear to be working. That said the circuit in the drawing should work as well and the led should blink I’d expect and it would be useful to find out why it doesn’t. If you attach the 1K resistor and led to the output of your working circuit changing the input between 0v and 4v should turn the led on one direction and off the other (I’m too lazy to figure out which is which right now 
). How does the power supply blow the op amps? Do you know? 30 volts shouldn’t be over voltage.
Peter
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25 hole Breadboard
This needs a new part. I have some of these but haven’t gotten around to making a part yet. Since Qt is screwing me around, perhaps I’ll make one as it looks to have a better chance of working with less frustration than Windows and Qt .
Peter
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Testing OP-amps
After I figured the op-amp needed pwr - it’s missing from his SCH -, the 3 op-amps put out the correct voltages.
I might play with the other circuit latter.
It’s the popular and cheap Ebay 0-30V 3A power supply kits that people have posted is under designed.
People got so fed up with failures they mod them, and one of the mods is replace the TL081 with the beefier TLE2141. The last failure was the 9015 trans, but I RnR and socketed the TL081s because I didn’t know if they were good. With this failure I pulled the 4 transistors and 2 Zeners(5V) and they checked out fine, the 3 op-amps pass that test, and the in circuit test of the other 8 diodes checks out fine. It doesn’t look like the op-amps are failing so I will have to look elsewhere, but on the other hand another kit is only $8.
Here is 80 pages of it, but I’m not going to read all that.
This page has Rev7 of the mods.
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25 hole Breadboard
Thanks a bunch Peter. I thought there was a way to change the number of holes/size of the breadboards, but I just remembered it is the perfboard that one can change.
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Testing OP-amps
Ah, the op amps that are failing are in the power supply. That makes more sense. I was thinking the power supply was powering the op amps that were failing. Too much output current is one likely cause, but the tl081 claims to be output short circuit protected. I’d expect the 2n3055 output transistors to be the most likely failure point as they are taking the most current. I’d say you would be better off replacing the circuitry after the transformer/filter capacitors with one of these though:
$2 US with up to 5A current limiting in a switching power supply (doesn’t need the large heat sinks). If you need pots on a panel just unsolder the 2 pots and replace them with wires
Peter
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Testing OP-amps
If I didn’t already go to all the trouble of building a whole PS with it a while back, and that it can go down to 0V, like you said, it’s probably not worth the effort when there are so many PS modules these days.
I did build another with twin SEPIC buck-boost modules (1.25V-45V), it’s just that those don’t have the adjustable current limit.
I tossed all the blown ATX internals and put them in the cases.
What I think blew it was that I was powering an ignition coil with my Arduino EFI, because all the displays on the PS’s went crazy, and soon after it didn’t work. The SEPICs survived.
Hopefully it won’t fail again, but if it does I might go for one of those RUIDENG DPS3003 32V 3A.
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DB37 Female connector
Hi All,
Is it possible for someone to help me out by providing a DB37 female connector.
https://fr.rs-online.com/web/p/connecteurs-sub-d-a-souder-sur-ci/1217340/
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DB37 Female connector
This should do what you want. As always you need to print out the pcb footprint and check it against a real part before ordering boards.
DB37F.fzpz (13.9 KB)
Peter
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DB37 Female connector
Thank you very much Vanepp
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DB37 Female connector
You are most welcome. For me it is fairly easy, just clone the existing db25 female, take it apart and add the new pins. If you aren’t already familiar with parts creation it is a lot more difficult.
Peter
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DB37 Female connector
Hi Vanepp, it woul be nice if you had some quick instructions or tips on how you achieved this. Probably there is more skills necessary. Was it inkscape to make the changes? or was it possible to do the new changes within fritzing itself?
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DB37 Female connector
I used Inkscape to edit the svgs, it can’t be done from within Fritzing AFAIK. It took me around a year to go from never heard of and svg or Inkscape to being able to make parts as the learning curve is quite steep (inkscape alone is quite complex). Here are pointers to a couple of tutorials which apply to the current version of Fritzing (most others I’ve seen are for earlier versions):
Other than that, your best bet is to try it and ask (preferably posting the .fzz or .fzpz file that doesn’t work) here for assistance (thats how I learned).
Peter
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Part request to apa102-2020
Okay, sharing the project will be on my list,
btw, I just visited the company here in TW had some talk with the manager, and complaint about everybody thinks, the poor datasheet dimension quality.
It turns out that the datasheets are more clear when sizing now,
not sure if its because my complaint anyway.
5050: apa102c-5050 (c is a cheaper package, and possibly made in China)
http://neon-world.com/uploads/soft/20161012/1476266707.pdf
2020: apa102-2020 (8-pads as this thread using)
http://neon-world.com/uploads/wenjian/20apa.pdf
I heard that they are also releasing apa102 in 3535 / 1515 package, but the new datasheet are not released yet, they follow nearly the same 6-pads with apa102-5050, with different arrangement of pins, so its easier to chain.
and there is also a new 2020 package, with 6-pads only, for more easy/dense soldering! not-yet seen datasheet release,
please wait for my discovery
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Two-digit 7-segment led indicator
Hi there!
I did some investigation into SVG format and it turns out capital or small letters only differ in absolute and relative. So after two more hours of digging, I gave up and just fixed your version to have correct height using text editor. 
Pads looks pretty for me now even in production images, as fas as I can tell gerber now looks good too. I will check once more after printing and etching, but also I will appreciate if you could take a quick look.
2digit 7segment - 0.2.1.fzpz (14.5 KB) (same prefix so it will overwrite existing part)
Your testscript gives one warning, and I can’t decide if I should remove second copper definition – this is handy sometimes to have an extra keepout near the holes. What is the proper way?
This is a through hole part as both copper0 and copper1 views are present.
If you wanted a smd part remove the copper0 definition from line 43↧
Two-digit 7-segment led indicator
Looks fine to me. It is possible the fault is in the Fritzing gerber/pdf code rather than the xml.
Unfortunately the text editor is the usual best way to move paths around. If moved in Inkscape it uses translates to do the move and usually won’t remove them even if ungrouped. I’m thinking about seeing if I can figure out how to preprocess to remove translates in the check script as this should be a performance increase (translates require a matrix multiply at every rendering AFAIK).
This message is information rather than a warning. The part is correct as it stands, as a through hole part it wants pads on both sides of a 2 layer board and thus needs both copper1 and copper0. For an SMD part you only want the copper1 layer so the part is only on one copper layer and doesn’t interfere with the bottom layer. This tends to confuse new part makers (it isn’t documented anywhere that I know of) and thus this information message.
Peter
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Two-digit 7-segment led indicator
My bad, I even wasn’t able to properly understand the checker message – sure this is through hole component. Lesson learned – don’t do this in the late night.
Looks like I can no longer edit my original post to update the part. Hopefully people will read the topic or visit my github before downloading corrupted version.
Thanks again for all the help! 
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