# My build progress **URL:** \ **Category:** DIY STUFF\ **Created:** [March 1, 2020, 8:57pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345 "2020-03-01T20:57:53Z")\ **Posts on this page:** 20\ **Page:** 75
**Author:** ![analogoutput](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/analogoutput/32/29663_2.png) [@analogoutput](https://lookmumnocomputer.discourse.group/u/analogoutput)\ **Post date:** [October 6, 2020, 7:56pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1492 "2020-10-06T19:56:07Z")
One great thing about Kosmo is that essentially it’s electrically identical to Eurorack. (There’s no +5V rail and no CV/Gate lines on the power header, but very very few Eurorack modules use those either.) The only difference is the panel size. In principle you can take (almost) any Eurorack module PCB and mount it behind a Kosmo panel. Except of course Eurorack uses 3.5 mm jacks, and usually Eurorack knobs and switches are too close together for Kosmo users’ tastes. So most board-mounted components need to be replaced by panel-mounted ones, wired to the pads that would have been used for the board mounted components. And you may have to rig up some kind of bracket or standoffs to mount the PCB if it was originally designed to attach to the panel via those same board mounted components. Or in some cases there’s a main PCB and a panel PCB, in which case you could design a Kosmo-sized panel PCB that connects to the main PCB. This is called Konversion. So there’s some work involved, but if you do it then there are hundreds of Kosmo DIY boards on the market, mistakenly labeled as Eurorack. [One example.](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1150) ---
**Author:** ![juggle](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/juggle/32/6100_2.png) [@juggle](https://lookmumnocomputer.discourse.group/u/juggle)\ **Post date:** [October 6, 2020, 8:06pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1493 "2020-10-06T20:06:38Z")
> [@ChristianBloch](#): > > Hot air _can_ damage components, but the ICs are made for it and can take quite a bit. Just use low melting point paste and go to something like 300 Celsius and I bet you’ll be fine. Yep. Most IC’s datasheets will give details on the temps. And that’s for oven reflow where they’re totally baked. With handheld hot air unless you’re reckless you’ll probably never reach those levels. I’ve done fine pitch CPLD’s and FPGA’s by hand and it’s possible…but much easier with hot air. In the video I was lingering longer than required with the hot air - I was still getting a feel for it and learning how to tell when it had actually liquified. Plus trying to record and solder at the same time was a new experience as well 😃 I usually keep my hot air station at 316c - but that’s measured in the handpiece. So I expect the air to loose a bit of heat on the way out. I use MG 63/37 paste (cat no 4860P-35G) and keep it in the fridge when I’m not using it. One syringe has lasted me over 5 years and is still mostly full despite having done about a dozen boards of various complexity. Technically it’s probably “expired” by this point…but still works just fine for me. Again as DIY hobbyists we can get away with a lot that wouldn’t fly for industrial production. I don’t think I’ve ever damaged anything with hot air yet (as far as I know…though I do seem to be having issues with the SMT DAC on my current project) but I have damaged parts in the past with an iron and too high of a temp back when regulated irons were less common. There are also fairly cheap reflow ovens - but they tend to require quite a bit of work to make them usable. The T-962 is the popular one and about $200 from the usual places. Info on upgrading and fixing it here: [GitHub - UnifiedEngineering/T-962-improvements: Improvements made to the cheap T-962 reflow oven utilizing the \_existing\_ controller HW](https://github.com/UnifiedEngineering/T-962-improvements) Here’s a good video on some of the options and updating a T-962: [https://www.youtube.com/watch?v=DYrucIWig24](https://www.youtube.com/watch?v=DYrucIWig24) Honestly though it looked like he got more paste than necessary on even with his stencil. Not sure if it was his stencil or his technique…but I generally use considerably less than he did. They’re eurorack…but some of the nonlinear circuits modules are small/cheap/simple enough they may be good first SMT projects to get a taste for it and you can always re-panel them for Kosmo if you prefer. ---
**Author:** ![analogoutput](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/analogoutput/32/29663_2.png) [@analogoutput](https://lookmumnocomputer.discourse.group/u/analogoutput)\ **Post date:** [October 6, 2020, 8:15pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1494 "2020-10-06T20:15:58Z")
How did you learn the hot air process? In person instruction, YouTube videos, trial and error… ? ---
**Author:** ![ChristianBloch](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/christianbloch/32/56_2.png) [@ChristianBloch](https://lookmumnocomputer.discourse.group/u/ChristianBloch)\ **Post date:** [October 6, 2020, 8:45pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1495 "2020-10-06T20:45:56Z")
YouTube. In particular, Dave Jones has a few helpful ones: [![](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/2X/0/0629edeb59a23c44d27c6852fa84a1c41cd1be46.jpeg "EEVblog #346 - MLF/QFN SMD Reflow Soldering") ](https://www.youtube.com/watch?v=M_rO6oPVsws) [![](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/2X/6/60ff9dc993aa0c86ae6ef74df2f8a7e5672e85df.jpeg "EEVblog #415 - SMD Stencil Reflow Soldering Tutorial") ](https://www.youtube.com/watch?v=qyDRHI4YeMI) ---
**Author:** ![juggle](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/juggle/32/6100_2.png) [@juggle](https://lookmumnocomputer.discourse.group/u/juggle)\ **Post date:** [October 6, 2020, 9:08pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1496 "2020-10-06T21:08:21Z")
Mix of youtube and trial and error. Honestly I found it was a lot easier than I expected once I finally tried it. ---
**Author:** ![analogoutput](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/analogoutput/32/29663_2.png) [@analogoutput](https://lookmumnocomputer.discourse.group/u/analogoutput)\ **Post date:** [October 6, 2020, 9:33pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1497 "2020-10-06T21:33:19Z")
The comments on those prominently feature the kind of know-it-alls I was talking about, graciously explaining how his technique could never work… ---
**Author:** ![Jos](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/jos/32/151_2.png) [@Jos](https://lookmumnocomputer.discourse.group/u/Jos)\ **Post date:** [October 6, 2020, 9:36pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1498 "2020-10-06T21:36:10Z")
> [@analogoutput](#): > > mistakenly labeled as Eurorack Ha, ha, now that I call funny 🙂 ---
**Author:** ![ChristianBloch](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/christianbloch/32/56_2.png) [@ChristianBloch](https://lookmumnocomputer.discourse.group/u/ChristianBloch)\ **Post date:** [October 7, 2020, 4:57pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1499 "2020-10-07T16:57:44Z")
I built the Erica Polivoks filter and it’s great. The resonance is wild in the best possible way. ![image](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/2X/4/49915ab21d6f44a798326170aac6bad632b1d62c.jpeg) Except there is an issue with their DIY files. It appears Pusherman is also also selling this panel PCB with the same error: ![ERICA-vcf](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/2X/b/b00c694e1030cccdaef8828d4683c9becdd28f49.jpeg) Let me know if you need help spotting it 🤪 ---
**Author:** ![eric](https://avatars.discourse-cdn.com/v4/letter/e/898d66/32.png) [@eric](https://lookmumnocomputer.discourse.group/u/eric)\ **Post date:** [October 7, 2020, 4:58pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1500 "2020-10-07T16:58:59Z")
CV1 Level, CV2 Level and In Level labels are swapped ? ---
**Author:** ![analogoutput](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/analogoutput/32/29663_2.png) [@analogoutput](https://lookmumnocomputer.discourse.group/u/analogoutput)\ **Post date:** [October 7, 2020, 5:19pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1501 "2020-10-07T17:19:00Z")
You wanted to repanel this for Kosmo anyway, right? ---
**Author:** ![ChristianBloch](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/christianbloch/32/56_2.png) [@ChristianBloch](https://lookmumnocomputer.discourse.group/u/ChristianBloch)\ **Post date:** [October 7, 2020, 5:23pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1502 "2020-10-07T17:23:20Z")
Yup… ---
**Author:** ![CTorp](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/ctorp/32/15023_2.png) [@CTorp](https://lookmumnocomputer.discourse.group/u/CTorp)\ **Post date:** [October 7, 2020, 5:59pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1503 "2020-10-07T17:59:04Z")
@ChristianBloch, Wow, that’s kind of annoying… ---
**Author:** ![d42kn355](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/d42kn355/32/273_2.png) [@d42kn355](https://lookmumnocomputer.discourse.group/u/d42kn355)\ **Post date:** [October 7, 2020, 7:28pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1504 "2020-10-07T19:28:19Z")
Hills: Playing around with a design based on a section of the [Kaussutronics Variable Waveshape LFO](https://kassu2000.blogspot.com/2015/10/variable-waveshape-lfo.html). ![triangle to sine](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/2X/e/eca76790663cd89b890b4b36cec8f575624bf471.png) The Triangle to Sine Convertor section is what piqued my interest as I am working on a device that produces 6 variable triangle waves (called Slopes/Swoops) and figured this would be a great addition to my design! ![variableshapelfo](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/2X/1/1cc2827bdb04afba46f0bd610e094e6359769c58.png) Further reading and diagrams show the Triangle wave section above heading on down to the TL074 and I cut off the upper section as that will be the input. ![hills2](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/2X/e/eb85b8387044991b7434bc85024e9840b1f3f606.jpeg) I decide to “Peter-ize” the schem in the form of a Paper Circuit ala ciat-lonbarde. ![hills1](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/2X/8/8472dc59b75c41edd9b7f0488367ec7e6b603235.jpeg) And just finished up the final version of it ![hills](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/2X/f/fd85b761d245d44aa38c359d4fcd1729bf001eef.png) I need to breadboard and test the circuit out, but hopefully it should have no issues! ---
**Author:** ![Jos](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/jos/32/151_2.png) [@Jos](https://lookmumnocomputer.discourse.group/u/Jos)\ **Post date:** [October 7, 2020, 8:03pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1505 "2020-10-07T20:03:29Z")
Can you upload an audio example showing the resonance? ---
**Author:** ![THOGRE](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/thogre/32/5189_2.png) [@THOGRE](https://lookmumnocomputer.discourse.group/u/THOGRE)\ **Post date:** [October 7, 2020, 8:22pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1506 "2020-10-07T20:22:16Z")
Like @Jos said, that would be great ! Erica did a lot of fantastic sounding modules ! ---
**Author:** ![antoine.pasde2](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/antoine.pasde2/32/326_2.png) [@antoine.pasde2](https://lookmumnocomputer.discourse.group/u/antoine.pasde2)\ **Post date:** [October 7, 2020, 8:34pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1507 "2020-10-07T20:34:48Z")
You convinced me, I just ordered an [858D for $39.99 +tax on Amazon](https://smile.amazon.com/gp/product/B01MR2IWBN/ref=ppx_yo_dt_b_asin_title_o00_s00) (I had this Amazon gift card that I was itching to spend.) ---
**Author:** ![juggle](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/juggle/32/6100_2.png) [@juggle](https://lookmumnocomputer.discourse.group/u/juggle)\ **Post date:** [October 7, 2020, 8:59pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1508 "2020-10-07T20:59:40Z")
Nice, I thought I paid more but just checked and the one I got was only $47 and has come down to $46. But it includes a bunch of tweezers, tools, and a spare heating element: [https://www.amazon.com/gp/product/B07FBGFT3K/ref=ppx\_yo\_dt\_b\_search\_asin\_title?ie=UTF8&psc=1](https://www.amazon.com/gp/product/B07FBGFT3K/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1) One thing I learned the hard way. The “tips” actually have a small dimple on them and twist into position. It’s very subtle though and easy to miss…which I did the first few times I used it. So I push pushed them on and pulled them off. Which eventually led to the one I used the most breaking. I got a set of new [tips from banggood](https://www.banggood.com/6Pcs-35681012mm-Circular-Nozzles-For-Hot-Air-Soldering-Station-858A-858D-p-1029750.html) for a few bucks that included more sizes though so it worked out in the end. ---
**Author:** ![ChristianBloch](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/christianbloch/32/56_2.png) [@ChristianBloch](https://lookmumnocomputer.discourse.group/u/ChristianBloch)\ **Post date:** [October 7, 2020, 9:58pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1509 "2020-10-07T21:58:06Z")
I guess they figured it out themselves 😀 ![Screen Shot 2020-10-07 at 14.56.40](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/2X/2/229f3533b700be15eb55acaaf381239037b4f1c4.png) ---
**Author:** ![ChristianBloch](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/christianbloch/32/56_2.png) [@ChristianBloch](https://lookmumnocomputer.discourse.group/u/ChristianBloch)\ **Post date:** [October 7, 2020, 10:23pm UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1510 "2020-10-07T22:23:02Z")
Here you go: [![](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/2X/5/546f113f29fadf65d34422cdc6c5022bcfea50d2.jpeg "Erica Synths Polivoks VCF Resonance") ](https://www.youtube.com/watch?v=snApfcvfaLc) ---
**Author:** ![d42kn355](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/d42kn355/32/273_2.png) [@d42kn355](https://lookmumnocomputer.discourse.group/u/d42kn355)\ **Post date:** [October 8, 2020, 12:30am UTC](https://lookmumnocomputer.discourse.group/t/my-build-progress/345/1511 "2020-10-08T00:30:53Z")
Decided to print it out and build it today! ![image](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/2X/6/6410e7985d8194976d5083ad7edd59340c012812.jpeg) Just missing the J201 which are on the way! ![image](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/2X/d/d7ff563bdf522b10f6d3bbb7f6ea3e4d09ae28ee.jpeg) Here’s where the art is 😃 [Previous page](https://lookmumnocomputer.discourse.group/t/my-build-progress/345.md?page=74) [Next page](https://lookmumnocomputer.discourse.group/t/my-build-progress/345.md?page=76)