So here is the strange behaviour vs. normal.10-20 degrees jumps can be seen like a delay in mantaining the set temp. The same backboard was used in this test,same cables,same power source,same oled display...only front boards are different ones.Every semiconductor was changed,no change.Resistors visually checked,capacitors from same batch,all pieces translated to another new board,no change...I am out of ideas... All looks ok,I can calibrate...In the calibration menu I can see room temperature jumping3-4-10 degrees back and fort and I have no ideea why,the U4 was replaced with no luck,even replaced with a resistive divider to simulate stable 750mV on output wich is supposed to deliver at 25°C.The vref looks stable...Really don't know what else to try...Anyone has some ideas? Youtube Video
Hello! I really don't know for the moment what can cause this malfunction.I have the same firmware on both ,I even replaced PIC,reprogrammed...still the same.It seems to be stable If I set the temp to max 150 degrees,if I set a higher temp the deviation is raising to 10-20 degrees and fluctuate...The difference can be seen in PC software also,I will make a video side by side and post it later. Thank you for your answer.
Hello! I have built 2 Unisolder 5.2c boards and the backsides and one front are working perfectly.Other front side has a strange behaviour:the set temperature is fluctuating with 10-16 degrees ...Example when set to 280 is going to 285-280-290-295-267-289...while the other board is staying almost perfectly on 280-279-280...When on calibration menu,room temp sometimes jump from 22 to 33-35 and back to 22 while on the other board is constant 22.Checked vref is ok,changed U4,acting the same.I am not sure what is causing this,seems like a noise or something.I can calibrate,I have checked soldering all looks ok.First front board works with every backboard with no problem very stable,but not the second one.Replaced U11,U10,U15,U4,U6,U16,the PIC,no change. Any ideas? Thank you very much! @romekplay That´s have been discussed before and the recommendation is to use 0.96 inch display for calibration There is much noise with bigger display,but unisolder will work ok.
Hello! So @minkok , I did what you have said,left the 2,2 µF capacitors in place and tested only on "Sleep side" R5-20K and R2*-110k and yes I get satisfactory response arround 0.3 seconds wich is good!Who is not satisfied with the response can try an 82K or even 47K as you have said but I have not tested and cannot know how stable it will be.Right now it is stable,not reacting on hand touching the plates,no "doomedahab" effect on boot!(@doomedahab I hope you don't mind that I called the effect with your knickname ) For me at least it is OK! L.E. R1,R4 left 10M
Using 5M instead of 10M doesn't give what we want,only increased noise and a delay when touching changing tip part(at least for me and once again I am using the sensing board inserted in the unisolder box not in the stand-don't know if it matters) so what I did was to keep the 10M resistors; I have changed the 2.2 micro capacitors with 1 micro to decrease delay at inserting and taking out the handle too but the doomedahab effect at boot was still there.Because I was satisfied with the changing tip part now,I have rotate the resistors only on the sleep part and used 165k for R2* ,20k for R5 and I am happy with the results.Act as it should at boot,got around 0.4-0.5s delay at wake from sleep,responsive at tip change,stable,doesn't react at hand touch.I think who is not satisfied with the delay can try an 500-680nF capacitor for C4. So,what worked for me was: C4,C5-1µF;R1,R4-10MΩ;R2*-165KΩ,R5-20KΩ;R7-330KΩ,R5*-20KΩ
Another videotest with initial values:R5,R7-330k;R2,R5-20k;R1,R4 10M starting from room temp.showing wake time from hold temp. much shorter but with the side effect noticed by doomedahab&morpheus-at boot,temp. raising to set temp. then coming back to holder temp. then acting normally. And showing the 5.2c reaching 330 quicker than JBC from room temp. (cold start)
Ok,here is a short clip showing the test with 20k,165k and 5M. And how its acting vs. my JBC CD 2E It seems the JBC is reaching the 330 Celsius quicker but actually the sensing circuit of the 5.2c with these values has a bigger delay at wake from hold temp. and in the 5.2c handle there was a bigger tip.At cold start,5.2c is booting faster R5,R7-20k;R2,R5 165k;R1,R4 5M
When I change the 330k to 20k and vice-versa,its working as it should at power on,but there is a 2s delay when I take the handle from stand until its boosting the temp.I tested with a 245 handle and I use the sensing board on the back board of the unisolder not in the stand.
@IT-Solve Hi! I saw you have some trouble with 5.2c.Well obviously it cannot be such a big difference between calibration and result.So,something is malfunctioning,not working as it should.It have been reported 10-20 degrees difference but not more.Minkok is doing a good job to help you!Hat off ! I am not aware of your soldering skills,but the 5.2c is not easy to solder.One of the back boards has driving me crazy for 2 days. I couldn't get to work the 3.3v part,the LM2675,wich is a simple buck converter.I suspected the ICs,got 6 of them;builded a protoboard with another LM2675 from the same batch on the bench wich was working fine,but not on the pcb...Desoldered the LM2675 from pcb,soldered on protoboard,worked,soldered back to pcb,fail...Desoldered all pieces from pcb,build on protoboard with wires and it worked...Soldered again all pieces and LM2675 starting with pin6(ground pin) first and finally worked.I suspect the ground pin was not soldered properly,the 5.2c has big thermal mass on ground traces so even If I checked under microscope and all looked fine there was not. So,do not give up! The working unisolder is a Great tool! If you can make high resolution photos of your boards,post the photos here and maybe some of the hawk eyes here can spot something wrong.Good luck!
Thank you for your outstanding and long contribution here,your posts helped me a lot. I am using that old design directly on the back board and works for me.I will order few boards to try the new design.It is 2mm pitch like old one,right? Thank you! A good day to all!
Even a direct short on D+/D- pins to miniusb port will work, no even need for the ADUM part at all if you are not interested in galvanic isolation. Many products does not contain an galvanic isolator chip at all.
@RCx03 You can check the display with an arduino,chech page 384 , but most likely the display is bad @Morpheus1979 The baihui solution is sexy! working good for me ;schematics belong to minkok I think. All images are from this forum.
I bought these from ebay to repair my unit.I cannot advise you if are chinese fakes or not,but they works(apparently are made in Malaysia).Seller is from Poland.Received them in few days by post. --------------------------------------------------------------------- Is there a way to buy from Farnell as an individual?Crazy these days to find something available... Good luck!
..."and you have to choose the right pinout in the sketch conform to your driver and connection" I mean you have to uncomment the coresponding constructor line according to your oled before sketch upload,for example here,a noname ssd 1309,128x64 oled connected as in the photo from the previous post.Of course you have to add the u8g2 library first Hope this helps! A nice day to all!
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(cold start)
