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Topic: Really universal soldering controller (Read 817903 times) previous topic - next topic

Re: Really universal soldering controller

Reply #2115
[quote author="Doomedahab"]I assume calibrating to exactly the resistor value should result in a perfect setting at the melting point of 37/63 solder with an average tip size, correct? But if I want to have a little higher temp setting to compensate for the drop in the curve, I could just turn the potentiometer a little?[/quote]
Nop, calibrating in calibration menu give you a working tool, but fine tune by RC2 in working mode will give you what you want.
Sometimes you can go out of RC2 regulation, all of that is already explaned.
Please read the tread, dont just ask.

Re: Really universal soldering controller

Reply #2116
Hi Minkok,

Believe me, I read all posts at least twice, the fine tuning in working mode is not explicitly mentioned anywhere as far as I can see, but of course i could have missed it. The thread is 143 pages long now so it's very possible that I could have found it mentioned somewhere.

I am aware that I can select different resistor values 1.3K/1.8K for R57, R59, to improve the range up or down if you cannot match the resistor value. In my case, I am juuuust able to get to the resistor value at the end of the range of the digital pot.

But it was unclear to me whether this same mechanism would apply to get the range you want from the tips you use (e.g. bigger tips run cooler, so if you use a lot of big tips you could adjust RC2 accordingly). But thanks for confirming this is the case :-)

Re: Really universal soldering controller

Reply #2117
[quote author="Doomedahab"]The only difference between this board and the last is that I now use ftz705 instead of ftz605, which is basically the same part.[/quote]

Ok, another noob question, please be patient ;-)

I quoted myself making a very stupid mistake here. These parts are each other's complementary parts, so no they are not "basically the same part"...

Nonetheless, even though the ftz605 is a positive voltage trans darlington and the ftz705 is a negative voltage version, my unisolder works just fine. Would anyone care to explain what happens here, just to learn something to a nitwit like me?

Re: Really universal soldering controller

Reply #2118
Wow! I didn't bother to check what FZT705 is and assumed that you're know what you're doing. )
I'm seeing two cases:
Q1 is already dead and just shorted.
It's BE acts like a 12V zener and through R2 provides enough current for regulators to work. But the resistor should be glowing then.

Re: Really universal soldering controller

Reply #2119
With Q1 shorted the whole thing would not work I presume? I soldered quite a bit yesterday with this death trap :) r2 seems fine, no discoloring or anything. Anyway, I ordered the correct part now and it will arrive tomorrow.

Re: Really universal soldering controller

Reply #2120
[quote author="Doomedahab"]Hi Minkok,

I am aware that I can select different resistor values 1.3K/1.8K for R57, R59, to improve the range up or down if you cannot match the resistor value. In my case, I am juuuust able to get to the resistor value at the end of the range of the digital pot.

But it was unclear to me whether this same mechanism would apply to get the range you want from the tips you use (e.g. bigger tips run cooler, so if you use a lot of big tips you could adjust RC2 accordingly). But thanks for confirming this is the case :-)[/quote]
Hello Doomedahab, you dont need to adjust each time RC2, the time you cange the tip with the same brand (JBC) and same series, but you may be need to do that in the other cases.
On page 85 I had similar problem and you can read what I did.

Re: Really universal soldering controller

Reply #2121
[quote author="minkok"]Hello Doomedahab, you dont need to adjust each time RC2, the time you cange the tip with the same brand (JBC) and same series, but you may be need to do that in the other cases.
On page 85 I had similar problem and you can read what I did.[/quote]

I had bookmarked this page already, I did not realize this was you :-) Looks like changing R57 / R59 to 1.8K should get me the temperature I need, thanks Minkok!

Re: Really universal soldering controller

Reply #2122
[quote author="Doomedahab"]With Q1 shorted the whole thing would not work I presume? I soldered quite a bit yesterday with this death trap :) r2 seems fine, no discoloring or anything. Anyway, I ordered the correct part now and it will arrive tomorrow.[/quote]

I ordered some NZT605, they came in today and I replaced the wrong part with this. Works perfectly. Nothing seems so have been damaged by using the PNP part, which continues to puzzle me. There is a difference in the operation of my unisolder now however: calibration is spot on at the melting point of 63/37, while previously there was a 6 degree offset between the display and the actual temperature. I will test at higher temps to see if this holds true.

Re: Really universal soldering controller

Reply #2123
I managed to calibrate my unisolder to within a few degrees celcius after replacing R57 and R59 with 1.8k resistors. I found some pure lead (on my roof haha) and it starts to melt at a display temperature of 326 degrees. Taking measurements with my biggest tip (4.8mm) on my hakko temp probe shows the temperature is accurate from 250 to 400 degrees, give or take a few degrees up or down. I'm happy!

Re: Really universal soldering controller

Reply #2124
Hi everyone,

I've almost finished building my UniSolder controller. Unfortunately, the OLED is behaving strange. As long as it's in the "default" mode (Currently showing "No instrument" as there's no instrument attached), all is fine, but it's flickering heavily whenever I change the temperature or go into the menu. A video of the behaviour can be seen here: https://photos.app.goo.gl/sxLYt6KYHAuNwHra7
Can anyone point me in the right direction as to what might cause this?

Thanks a lot,
Mathis

Re: Really universal soldering controller

Reply #2125
db9mat, did you see the flickering exactly as in video, or camera sync adds to the distortion?
Please share some information about this screen and where did you get it.

Re: Really universal soldering controller

Reply #2126
Flickering is exactly as seen in the video, unfortunately.

I got this display: https://www.aliexpress.com/item/1pcs-0- ... 4c4dPkQMaA

It was recommended by a fellow user in this thread. Doesn't mean that I got the exact same hardware as he got when he ordered though...

Re: Really universal soldering controller

Reply #2127
Maybe there is a power outage on VDD or VCC, since as long as pixel fill is low it works OK. Or the screen is just defective.
Are Q14 and Q16 OK? I see that Q18, Q19, Q21, Q22 is not installed on your board and are of the same type as Q14 and Q16.
I've noticed, that some times the controller looses current regulation and the brightness of some parts of an image becomes much higher. It's really weird.

Re: Really universal soldering controller

Reply #2128
I received my sensor pcb and I am building it up right now. I always assumed the sole connection would be via the rj11 connector, but there's also a 6 pin header. What is it for? I cannot find clear pictures of it being connected to anything, and I am not able to figure it out from the schematics unfortunately

Re: Really universal soldering controller

Reply #2129
[quote author="afedorov"]
Are Q14 and Q16 OK? I see that Q18, Q19, Q21, Q22 is not installed on your board and are of the same type as Q14 and Q16.
[/quote]

You're very observant! Correct, Q18-22 are missing. I forgot to order the IRLML6401s and replaced Q14 and 16 with NDS356As (also P-Channel MOSFETs, but with higher R_DS,on) as I thought they're "just" for turning on VCC and VDD to the OLED. But you think they might be the cause for this problem? The proper FETs are on their way and should be here tomorrow. I'll replace them and report back if it fixes the problem.

Anyways, thanks a lot so far,
Mathis