Any opinions on the AiXun T3A?

[drksy]

It’s interesting to point out what the seller wrote to me after realizing my station buzzes. I’m attaching the video I sent to the seller for those who haven’t experienced this buzzing problem

https://youtu.be/Imbg9Skw5vQ

He wrote:
机器里面的一个小元器件坏了，为了确保万无一失，我们直接安排补发一个新的主板给你更换

This translates to:
A small component in the machine is broken. In order to ensure nothing goes wrong, we will directly arrange to issue a new motherboard for you to replace

Suggesting that he’s aware there is a “broken” component on the control board. Maybe it’s worth investigating what this mysterious small component is and why it would cause buzzing in the handle and the station. At least this might help future owners of the Aixun product who will inevitably suffer from this same issue.

[dreamcat4]

it sounds pretty innocent comment imho... (most likely either a capaciitor or resistor i would expect)

[drksy]

it sounds pretty innocent comment imho... (most likely either a capaciitor or resistor i would expect)

Well, looking at the schematics here (by c0d3z3r0)
https://github.com/c0d3z3r0/aixun_t3a_rev/blob/master/schematics/aixun_t3a.pdf

It's really quite a simple board. What resistor or capacitor would you suggest checking? Maybe R6, R11, or maybe it could be just a bad MOSFET?

The high power path from the supply to the mosfet to the tip back to supply is pretty short. What could cause it to buzz this way other than poor electrical connection?

[tony359]

Hi

Didn't realise there was a larger thread on the T3A! I posted a question about some overshooting observed with a genuine JBC tip here: https://www.eevblog.com/forum/reviews/aixun-3ta-overshooting-with-jbc-tip/msg5057971/#msg5057971

The video of the behaviour when testing on a thermometer is here: https://youtu.be/z6oj99W5PH0

I don't see the same behaviour with a smaller, Axiun tip. Axiun commented it's intentional

Any feedback from other owners?

[c0d3z3r0]

Hi

Didn't realise there was a larger thread on the T3A! I posted a question about some overshooting observed with a genuine JBC tip here: https://www.eevblog.com/forum/reviews/aixun-3ta-overshooting-with-jbc-tip/msg5057971/#msg5057971

The video of the behaviour when testing on a thermometer is here: https://youtu.be/z6oj99W5PH0

I don't see the same behaviour with a smaller, Axiun tip. Axiun commented it's intentional

Any feedback from other owners?

Wat? intentional? How would they even know if Aixun or JBC tip is connected lol

Aixun further commented on my query and stated that being a "non-Axiun" tip, "there maybe some little unstable factors occured during soldering". Uhm...

Well, yeah, ok... so they behave differently because they are not exact clones... "unstable factors occured during soldering" is bullshit...

[c0d3z3r0]

Edit(24.07.2023): I did temperature calibration today with my trusted Omega K type temperature probe and the temperatures are very accurate with firmware v1.33 - when unit is set to 350C I get steady 347C on the temperature probe, without any fluctuations whatsoever. With v1.34 the temperatures were jumping up and down like crazy.

Is this the same behaviour like shown in this video or worse? Can you make another video?

[tony359]

Is this the same behaviour like shown in this video or worse? Can you make another video?

Ehm... that's my video

But yes, I see others are reporting the same.

I tried 1.33 and the issue disappeared completely!! Magic thank you!

I kind of like the idea that the station is giving a "kick" to the tip whenever I am touching a solder joint but I don't like the idea that if the joint is small I end up with +40C from the setpoint! Maybe it's a good idea but it might need a little refinement!!

Wat? intentional? How would they even know if Aixun or JBC tip is connected lol

Well, yeah, ok... so they behave differently because they are not exact clones... "unstable factors occured during soldering" is bullshit...

Yep, 100% Marketing BS.

[dreamcat4]

So let me understand something correctly:

I am on v1.26 firmware with the original T3A hardware.... is it worth now to upgrade it to the v1.33 firmware? Anything else worse on it?

But the 1 thing i was missing was to be able to press a button on front panel. To manually force sleep mode when the handle is still off of the stand. Yet I could make some simple hardware hack for this, (to install some new dedicated physical switch). So that is not actually matters to be required absolutely in the firmware so much.

[c0d3z3r0]

Is this the same behaviour like shown in this video or worse? Can you make another video?

Ehm... that's my video

Sure, look at the quote I was asking  sushi1808, who reported on  July 21, 2023, 06:02:31 am

[tony359]

ah ops sorry!

Anybody else reporting the same? It could be me but I feel the station is noisier with 1.33? As it buzzes - previously it didn't or in a much less noticeable way?

[tony359]

Tonight I used the T3A for some proper soldering for the first time.

At some point I saw the display going "NO TOOL" intermittently. I thought it was the tip so I swapped the JBC I was using for an Axiun and it happened again after a little while.

THEN I realised that it would ALWAYS happen on SOME pins of the motherboard I was working on? The motherboard was fully disconnected and the battery had been removed. The board had been sitting there for days so capacitors should have all been discharged.

Can someone comment on this please? What do I do? Is this a faulty unit? I'd understand an intermittent contact but not something like this!



This is what appears on screen when it happens

[c0d3z3r0]

Wow, that looks really weird! o.O

[mebel]

It's not a kind of board, what matters is that you keep the handle higher. I know it's strange but please check it.

[canetoad]

Hi,
by being a dumbass I got two T3As with the 245 handle. (Un)luckily I got one that is buzzing with the PWM one isn't. Both of them working V1.3 models and produced on the same day (2023.08.11 for the record) per the QC-passed card.

So I can conclude that it's not an issue of the hardware revision, since there were reports from before the V1.3 was available.

I already checked out that it's not the plug, as applying some force on it, does not fix the issue or the sound of it, which i would expect if it's just a bad connector. But the sound is definitely coming from the front.

Sadly I don't have the tools to remove the front panel. If somebody (maybe @c0d3z3r0?) wants to investigate further, I would be willing to loan the noisy unit out (and would also pay for shipping of course).

Best,
canetoad

[Joebeazelman]

Do you have a clothes iron and a piece of fabric (t-shirt) or a sheets of paper? If so, put the iron on its lowest setting, place the fabric or sheets over the screen and apply the iron. Check every so often until the glass temperature reaches 60-70C. The fabric distributes the heat. Delaminating is an excellent skill to learn in electronics as adhesives are becoming more common. Watch SteveyG's video on the Aixun T3A review. He shows how to disassemble the unit and remove the screen.

[chconnor]

I was shopping for the T3A at the easy100fix store -- what is the difference between the $112 "T245 set 110V" and the $129 "T245 B 110V" -- is it that the second one includes the cradle, and the first does not?

[dreamcat4]

correct.
(and yes: you want to get the 'b' set, it is worth it)

[chconnor]

Thanks! -- was just coming back to answer my own question... the non-B has a cradle, but it's the simpler/earlier folded metal one, right?

[canetoad]

Do you have a clothes iron and a piece of fabric (t-shirt) or a sheets of paper? If so, put the iron on its lowest setting, place the fabric or sheets over the screen and apply the iron. Check every so often until the glass temperature reaches 60-70C. The fabric distributes the heat. Delaminating is an excellent skill to learn in electronics as adhesives are becoming more common. Watch SteveyG's video on the Aixun T3A review. He shows how to disassemble the unit and remove the screen.

After further investigation i discovered some more things: Apparently they changed the design of the glass so it doesn't fit around the knob anymore, you need to remove it first, which they seem to have glued on as well, as pulling and light prying don't seem to get it off.

My first idea was using a hair dryer, but I'm also missing a spudger to get into the small gap around the glass. Over time I will probably buy this stuff, but right not right now as I'm also buying a lot of the other beginner stuff (and of course I was a dumbass and ended up with 2 T3As).

It's probably just some microphonics in one of the MLCCs and I will see if I get something nonconductive over the next few days and see if poking them will change the sound.

[c0d3z3r0]

@canetoad it might be worth testing if supplying with a high(er)-quality SMPS changes anything regarding the noise. Also, you could try just swapping the two SMPSs and see if that changes anything

[drksy]

@canetoad it might be worth testing if supplying with a high(er)-quality SMPS changes anything regarding the noise. Also, you could try just swapping the two SMPSs and see if that changes anything

The 24V jack in the back of the unit is tied to the output of the power supply. In addition to being an output, it can well be used to bypass the internal supply. This is exactly what I’ve already tried. I fed 24V from a linear bench supply (putting two channels in parallel to get a good amount of current). The result was that the buzzing did not change the slightest. It stilled was buzzing away.

Today, I’ve checked my mailbox, and look what I found. This was delivered to me from the Chinese seller that sold me the station




This suggests the seller thinks the buzzing is indeed caused by the power supply. My current suspicion is that the connection between the supply board and the control board is a bad one. Well, no choice now but to take it apart. Let’s see how this goes.

[tony359]

Both of them working V1.3 models and produced on the same day (2023.08.11 for the record) per the QC-passed card.

Did you get the HW revision from the display? I believe mine says 1.0?

It's not a kind of board, what matters is that you keep the handle higher. I know it's strange but please check it.

Is that a suggestion for me? What do you mean with "higher"? More perpendicular to the board?

I was soldering on a pre-heating board today, the PCB was touching the plates and I could hear some buzzing noise from where it was touching the plate when I was soldering. I love this iron but I am not impressed by the design so far.

[mebel]

Mine T3a was showing "no tip" when the handle was raised high.

[tony359]

Could you possibly elaborate on what "higher" means please?  

Anyways, if you watch the video this really happens when the PCB I am working on is grounded - regardless on how I keep the handpiece.

[c0d3z3r0]

Mine T3a was showing "no tip" when the handle was raised high.

Sounds like a connection issue, broken cable maybe