I find it impossible to buy right kind of trimmer pots on the first try. Good thing that I have electronics shop a couple of kilometers where I live. When I order something from them online and have it wait there for me to collect, they don’t even ask my name when I come to the shop. They just get my package the moment I step in from the door.
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You’ve got slight underextrusion (noticeable in the horizontal lines on the side of the tower) which can affect dimensional accuracy. Try calibrating your e-steps.
There’s an excellent printer calibration guide here:
https://teachingtechyt.github.io/calibration.html
He also runs an informative, accurate, and unbiased YouTube channel that I would highly recommend checking out if you’re at all into 3D printing.
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Don’t even get me started. Too late! For reasons which seemed good at the time I designed and had fabbed a module using not the usual Bourns 3296W (clone) trimmer that is so readily and cheaply available at Tayda but 3296P which is basically the same thing turned on its side: about 10 x 10 mm board area and 5 mm high instead of 10 x 5 mm and 10 mm, with side adjust screw. At Mouser and Digi-Key they have not only these but Bourns PV36P which as far as I can tell is exactly the same but a different shade of blue and Nidec Copal CT94EP which looks to be compatible. So I bought several PV36P from Digi-Key and was all set.
Except that (1) I didn’t actually buy enough, and (2) I only got 10k and I also need 50k.
OK, so I went back to Digi-Key and… they were out of stock on the 50k ones. All three: 3296W, PV36P, and CT94EP.
Jameco had them but charges a $10 fee on orders under $20. Mouser had the 3296W (only) in stock but they wanted $4.09 each, and I need a total of 5, and Mouser charges $8 minimum shipping, so that’s $28 for 5 trimmers. Digi-Key lists the 3296W for $2.43 and the CT94EP for $1.56 each with $5 minimum shipping. Do the math. If only they didn’t insist they can’t ship parts they don’t actually have any of, I’d be all set.
Mouser now has the PV36P at $2.37 each back in stock. Digi-Key says they’ll have the Bourns trimmers in stock in July but they show no lead time for the Nidec Copals. I could pay about $20 now or about $13 to $15 in July. If I wait until then the out of stock ones will be back in stock and the in stock ones will not be out, right? Right!
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yeah I needed trimmers to and went the china route , so they are cheaper but it will be a month before I can finish the last joy stick module.
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looks a wee bit tight there , do the old double stacked socket ?
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Yeah, the white cap was too large for that footprint. The caps barely fit between the sockets but the ICs overhang the sockets so there wasn’t enough room. I just took out the white cap and replaced it with another mounted on top of the grey one.
That’s one issue solved but pin 9 is the big problem.
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Have you considered filing a mil or so off the chip?
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230 volts shorted gives nice sparks. Seems that my new power supply was faulty. The transformer inside was actually loose, probably it was dropped during transportation and it had nicked the wires. First two times I used the power supply on a wall socket, so the transformer didn’t touch bare metal of the wires, but when I put it to other socket…
Well, it didn’t just blow the automatic fuse of my work space, but something deeper in the building so even the lights, which have separate fuse, don’t work. I think I need to call some maintenance dude tomorrow. Or maybe somebody else will before me if that affects also some apartments in the building
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So I lifted the white cap up over the gray one, and I bent pin 9 out and soldered a purple bodge wire to it, and then I discovered pin 8 did go into the socket but did not make reliable contact, so I soldered a green bodge wire to that. And… I think it’s working now.
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well thats not lack of progress , sure you been bodging around but it looks like you are moving forward .
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A List of Rookie Maneuvers - A Personal Diary
- Circuits work more efficiently when parts are soldered in place
- Resistor values are probably important to placement in the circuit; ditto capacitors
- 10P Box headers don’t work well when placed in reverse
- Some Op-Amps work better than other op-amps in a given application
- Rando 14-pin IC’s are NOT interchangeable (applies to Op-Amps too)
- Never assume that you socketed an IC correctly
- LED’s do have a direction unless it’s one of those Bi-Polar 2-pin weirdos
- Once in a while the problem is a bad IC
- Sleep is important
- Much can be seen by Looking
- Wires in a wire housing cause strange results when the order is reversed
- A broken PCB trace is an invitation to a Rabbit Hole
- Always consult the BOM and whatever Build Notes are available before panicking.
- Discussion threads on Engineering changes will consume you for hours but can make your life easier
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Let it be known that most every “show-stopper” in a build of a well designed project is one of these 14 points.
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I’ve been spending quite a lot of time in KiCad and on the breadboard working on a pole mixing multimode filter design.
Blog post #1, challenges and optimism!
Blog post #2, breadboard results and… not so much optimism.
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Have you considered changing your name to digitaloutput?
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Amazing what a good walk will do for your thought processes. I’d hardly set foot on the trail when I realized the pole mixing problem isn’t as serious a problem as I thought.
It’s an analog filter.
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I can always tell that when my thick head hurts while reading one of your posts that I have much to learn an absorb over the next couple of days. I’m never disappointed by what I have learned here, which is much!
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