Jump to content

All Activity

This stream auto-updates     

  1. Yesterday
  2. Work on adding TIG mode has begun. It has a dedicated discussion: https://www.rc-cam.com/forum/index.php?/topic/4710-add-tig-function-to-the-sparky-stick-welder/
  3. This is the experimental TIG Function discussion area for the Sparky Stick Welder Project. The TIG feature is being developed github contributor hogthrob. Please post all TIG related HARDWARE discussions in this thread. Post SOFTWARE issues at the Github repository in the open PR #6. https://github.com/thomastech/Sparky/pull/6 Important: Questions pertaining to the original Sparky project should discussed in the main project thread found at this link: https://www.rc-cam.com/forum/index.php?/topic/4605-sparky-a-little-stick-welder-with-big-features/
  4. Last week
  5. Earlier
  6. The physical location of Partom's pot suggests it is the video level adj. So give it a try. It's very unfortunate that the other board is missing the video adj pot. And it appears to be hand soldered and has a lot of flux residue. Disappointing to see.
  7. Oh i wish there is any quality Vtx available:( It looks to me that Patrom fox800 600mw Vtx is better in quality than RMRC 600mw Vtx and could you please suggest me if that pot on Patrom is actual a video level adjustment pot?I found nothing on RMRC Vtx to adjust video level:( Thanks.
  8. Thanks for the kind feedback. Sorry, but nothing to offer in that RF power category. After the product quality fiasco with Lawmate, followed by the Racewood factory closure, I evaluated several higher powered 1.3Ghz vTx's. None met my quality / performance expectations. That was several years ago and it doesn't appear anything has changed given what's available today. My workaround back then was to in-house modify an expensive 1000mW vTx from a China supplier (I forget the brand). With our modifications it was a reliable performer. But every sale was at a loss due to market pricing pressures. Did that for a couple years to support our customers. Unfortunately the mods were too time consuming and so we ended sales. Fortunately this was after the FPV market had shifted to 5.8GHz.
  9. Thanks Thomas for your suggestions!I am excited to wire my Oracle diversity controller and calibrate my system when it's installed. Anyway to get quality 600~800mw Vtx from dpcav?I really like your quality products.
  10. These observations are ongoing issues that the suppliers ignore. And the reason for the video calibration tool. You are now getting acquainted with the performance issues that haunt many FPV systems. Along with what you observed, be prepared to find that some systems will alter the video level after you change antennas. And sometimes whenever you change RF channels. These undesirable quirks are due to inadequate RF designs, mostly affecting the 900MHz-1.3GHz systems. I doubt the suppliers care and most users are unaware of these problems. The video cal tool not only allows you to properly calibrate a good set of components, it also helps you identify the bad performers that need replacement. I suggest calibrating the video levels after everything is installed and the desired RF channel has been set. Do the cal with the vTx and vRx several meters apart, preferable outdoors (less multipath from workshop walls). Replace the bad parts in installations that suffer a lot of video level instability as the model is moved around (will cause poor video performance in flight). Whenever **anything** in the FPV model or ground station is altered then repeat the video calibration. You're on your way to experiencing better FPV video performance. Your video diversity system should work better too. Enjoy!
  11. Success!! and thanks for your quick reply. I just swapped the vtx osd board with Rx and reflashed both and now it matches good.So it must be difference in the resistor value in one of them as you mentioned.Now i get same results on 7.5v and 12v.Picture attached. Now when i tried to check my actual two 1.3ghz Rx(both latest readymaderc comtech Rxs) and two Vtx(one 600mw RMRC and one bangood patrom 1.3ghz 600mw),i found they are not matched with each other. 1 patrom is matching with one RMRC Rx and 1 RMRC Vtx is matching with 1 RMRC Rx. One strange phenomenon i found that RMRC Vtx changes the video level a lot by turning its position but patrom Vtx doesn't do that.It remains constant even if i am turning it around.Does it mean that RMRC Vtx is bad?
  12. It appears that the two minimOSD boards are not identical, perhaps due to sloppy components. Some ideas to try: 1. Ensure battery voltage is at least 8V when powering the boards. 2. Retest with a different video patch cable connecting the two modules. Should be short, good quality. 3. Check the two boards' video input termination. With nothing connected, use a DMM and measure the Vin input resistance of each board (DMM across Vin & Gnd). They should be identical values (within 1%) that are very close to 75 ohms. If beyond 1% mismatch, replace the resistor that has the worst deviation (so it is a match). 4. There is also a 75 ohm series resistor on the video output of the MAX7456 chip. One end of the resistor is on the boards' Vout pin, the other is at the negative (-) junction of the two 47uF tantalum caps. Check them (meter across Vout and 47uF cap junction), should match within 1%. If beyond 1% mismatch, replace the resistor that has the worst deviation. If the resistor values are good matches then the easy answer is to just use the boards as-is; When you adjust a vTx video level you'll need to set it so that the image results match exactly what you saw in the validation test. That is to say, the upper right "T" area will have a subtle darkness, as displayed in your posted image.
  13. Hi Thomas, First of all i appreciate your all the work you have done towards fpv community!! So i assembled your tool but i am having little issue.When i connect both minimosd boards, the image on top left doesn't match perfectly between vtx and rx miniosd boards.Any way i can calibrate? or i have to get another set of boards.I did order both boards together from the same manufacturer on aliexpress.Could you please have a look at the pics?Thanks.
  14. And a diy variant (in Russian): and another version of above:
  15. Mr.RC-Cam

    Fleye

    Here we are four years later. The goflye drone's website is 404 and their Kickstarter campaign was vaporware. Some backers are still waiting for their refund. Yikes. https://www.kickstarter.com/projects/gofleye/fleye-your-personal-flying-robot/comments Too many cool sounding Kickstarter launches end up as product failures. Getting your money back is often painful, sometimes impossible. Glad I stay away from crowd funding platforms.
  16. An accurate schematic of the welding machine's PWM controller board could help us design alternate current control solutions. I don't have the free time to reverse-engineer the controller board, but perhaps someone else will volunteer to do that.
  17. A crazy idea: use A/D to convert the feedback and use that to calculate the output....naah :-)...digital POT is way easier...
  18. I did not find schematics to this welder. Having them would have saved a lot of time developing the Sparky Project. The current setting POT is sourced by the PWM chip's feedback path. I originally planned to use the ESP32's DAC to control weld current but had to abandon that idea because of the welder's feedback configuration. The MCP45HV51 digital POT was a convenient solution.
  19. Wonderful project and design! In fact I had almost exactly the same idea when I ordered the small yellow thing, it arrived today. I found this blog by searching the ZX7 combined with SG3525AP :-), trying to find a schematics, I guess you have not found them either? The high voltage digital pot is a good find. I planned to use an opto with PWM to control the current. Is the potentiometer just a constant voltage divider or is it driven with some sensing feedback? My goal is to build a lift arc TIG controller, let's see how it goes :-). Many thanks for sharing all the information!
  20. replaced litheum battery now i need to reset the radio jim stryjewski
  21. Just want to say, found this project through the Hackaday podcast and think it is genius. For one thing it give some much needed safety aspect to the original design but for another it is a great update with flexible scope for upgrades and other features. I have been arc welding for years but these little inverter welders I have never really used and the addion of pulsewelding is very interesting indeed. So I have bought one of this welders and will be working on converting it to a sparky over the next few months. Thanks for the inspiration.
  22. Surprisingly, this welder runs cool. As a test I burned a half-dozen 7018 rods uninterrupted at 85A and temperature rise was minimal. So I'd say that the IGBT transistors and oversized fan are helping out. In case of overheated silicon this welder has a thermal sensor to shut it down. And Sparky will voice announce the overheat alarm condition. But I have a feeling that this audio alert may never be needed. Oops, indeed I am guilty of a typo. This welder's PWM controller uses a SG3525A, not the SG325 nonsense I typed. - Thomas
  23. Aha... I see the light now. The smallish wire-gauge of the enameled magnet wire of the toroidal step-down transformer is so insanely small, that I thought it to be an inductor that isn't directly in the welding current path. The torroidal transformer-core is surely any one of the "standard" "power-materials" from the various ferrite-core suppliers. The core size itself is amazingly undersized (even at a 50 KHz switching frequency), but it obviously works! This unit, as with many similar units, probably have a 5% maximum duty-cycle so as not to allow all of these "undersized elements" (heat-sinks, silicon, and copper/aluminum windings etc...) to begin to glow red before permanently cooking themselves :>)). I agree with your assessment of the root-cause of the 15A 120VAC breaker tripping in that video. that concept crossed my mind after already having posted..... Also, I believe you meant to say SG3524 PWM controller. That is still one of my favorite ICs from way back.... Thanks for the reply. Keep on learning. I like your philosophy,
  24. In this design, a SG325 PWM controller chip and the IGBT transistors are used to switch (at 30 to 50 KHz) the rectified line voltage for the step-down voltage conversion. These drive the primary of a large Toroidal transformer (seen in the image in my previous post). The transformer's low voltage secondary is DC rectified. The reference patent claims the toroid's ferrite material is a special microcrystalline alloy. The toroidal transformer has independent primary and secondary windings. So the AC input and DC output are galvanically isolated. BTW, the low voltage controller supply (15VDC) is also isolated. It uses a TNY275P series chip and bobbin type transformer. I too have watched YouTube videos where the welder was tripping breakers. But they were using 115VAC outlets (versus 230VAC). A 80A welding current will trip a North American 115VAC / 20A circuit (80A x 26VDC / 0.85% = ~2450W). A dedicated 230VAC 30A-50A outlet is is recommended for common welding machines. The market is flooded with very capable Stick, TIG, MIG machines. So I could have bought my way into welder ownership. But I'm also drawn to interesting challenges and I like to hack. So I took a chance on a insanely cheap Chinese Inverter machine. Despite all its shortcomings, it seems to satisfy my needs. And it has given me the chance to finally try my hand at stick welding, something I've been wanting to do for many years. Exactly! Creating Sparky was interesting and a fun challenge. That's a reward of hacking. Even my failed hacks are a win, since something is usually learned along the way.
  25. I'm currently into the same Electrical Engineering "power conversion" related to welding mode. :>) The EE specs of the currently available Silicon power devices (IGBT's and MOSFETs) are simply amazing. Am I missing something, or does this "version" of a super-low cost IGBT-based AC-DC converter (in this case a Stick/TIG power supply) NOT have a ferrite, AC line-isolating switch mode step-down transformer? The "reference design" you post a link of is a nice schematic of a full-bridge (primary switching topology) IGBT-based step-down welding supply WITH said isolation transformer. This is a "standard" (and clearly much safer) design. In looking at the unit you are hacking, it basically looks like the design is an IGBT "buck-mode" DC-DC step down converter (the AC line is just bulk rectified with that full wave bridge) without ANY AC line isolation. Is this correct? This would also explain why in the other videos on these welders that they are tripping the AC circuit breakers feeding power to these units (although the unit's closed loop current regulation should somehow prevent this). It would also make me wonder why they would NOT have earth-grounded the chassis of this unit. Nice work. It makes me feel a little less stupid for playing with all of these things as you do, when I can easily go out and just buy a nice TIG machine. ...where is the fun in that though?
  1. Load more activity
×
×
  • Create New...