Yihua 898BD+ Soldering Station Review

[dflatfrog]

Here are the pictures of the board. Thank you all.

[icpart]

Here are the pictures of the board. Thank you all.

I think this PCB is the same as mine. If you can confirm if they used the Samsung MCU therefore they are the same.
Some time ago I was take a shots of my PCB board and if I can find them I will post them here for reference.
Aslso tactile switches of front panel are soldered on the another side of the showed PCB.

[dflatfrog]

Thank you.

Anyway, I lost interest in this tool and shipped it back to the seller.

[Guduroid]

If anyone can help me...

I got my station yesterday. Hot gun is working properly, but I have problem with soldering iron. Iron doesn't warming... On display is constantly 000 or 001 and dot is blinking constantly. Anyone knows what is the problem?  Station is brand new!

Thank you in advance.

[duskglow]

Thanks for this review.  I was looking at an 898D on eBay and was wondering if these were cheap pieces of crap.  Now that I see it's got the seal of approval of at least a couple of eevblog residents, I can buy with confidence.

I want to start getting into SMD, and this seems as good a time as any.

[SquidgyB]

Hello everyone.

I purchased an 898D+ from ebay last week, opened it up before switching on to check grounding etc - the board looked a bit shoddy, but nothing that stood out as dangerous or unfinished.

I used the iron and heat gun a few times in the last few days, and was quite impressed with it (my long running soldering gear was a really cheap iron and gun that have lasted me a good 10 years, surprisingly (you know, those cheap red ones available everywhere).

Anyhow, I switched it on today to do some work and... nothing. Checked the fuse: blown. Had a look at the main board: a resistor has died.

Here's a pic of the damage:



Can anyone tell me the value of this resistor?

Also, if anyone has working knowledge of the circuit - what does this resistor do and what would be the likely cause of it's demise?

I have the option of returning the unit, as it's been with me less than a week. Of course, if I can repair it myself (and be sure that the same issue won't crop up again) I will do that to save time and money. On the other hand, if there's another defect which might be causing this problem, maybe it would be best to send it back.

Any ideas/help would be greatly appreciated.

[MrAureliusR]

Hey. Only slightly off-topic but for those who are students/hobbyists (like me), a few months back a friend bought me the 937D Yihua soldering station -- which seems to be GREAT value for the price. It comes with 5 or 6 different tips and, at least for me, has been a great soldering station. It also came with a spare heating element, which is great. The tips are the same as a certain popular Hakko model so you can easily use the real Hakko quality ones. I'm going to check right now and see if my heating elements are Hakko as well...

Hmmm.. hard to tell. They have their specs printed on them but no company name. They feel good but with a heating tip who the hell can tell? More experienced eyes than mine, for sure.

showing the partially disassembled iron and the spare parts, spare heater on left
another shot of the same thing
Unit first switched on and showing 320 degress C
Unit starting to heat up to 320 degrees. Notice the heating light is on and it now shows 97 as it climbs towards 320
Cheap stand as mentioned in OP I jam extra tips and the scissor heatsink (which came with my old iron) into the holes around the edge... can't see any other purpose for those holes! I've never wetted the sponge as I have a steel wool cleaner (which you can see behind).

My impression of this unit (which cost around $55 CDN, delivered) is that while it may be a bit on the cheap side, it's done me very good so far. It goes waaaay beyond any temp setting I'd need. There is a similar version to the OP's that is black like mine but also has a heat gun. They also make a three-function one that has a built-in power supply!! I'd love to see THAT torn down, the power supply seems like a bit of an afterthought. Who knows though -- occasionally Chinese cheapies surprise me with their build quality.

If anyone is interested I can pop open my machine and take photos to compare.

[icpart]

Hello everyone.

I purchased an 898D+ from ebay last week, opened it up before switching on to check grounding etc - the board looked a bit shoddy, but nothing that stood out as dangerous or unfinished.

I used the iron and heat gun a few times in the last few days, and was quite impressed with it (my long running soldering gear was a really cheap iron and gun that have lasted me a good 10 years, surprisingly (you know, those cheap red ones available everywhere).

Anyhow, I switched it on today to do some work and... nothing. Checked the fuse: blown. Had a look at the main board: a resistor has died.

Here's a pic of the damage:



Can anyone tell me the value of this resistor?

Also, if anyone has working knowledge of the circuit - what does this resistor do and what would be the likely cause of it's demise?

I have the option of returning the unit, as it's been with me less than a week. Of course, if I can repair it myself (and be sure that the same issue won't crop up again) I will do that to save time and money. On the other hand, if there's another defect which might be causing this problem, maybe it would be best to send it back.

Any ideas/help would be greatly appreciated.

I can open and view the value of resistor of mine BEB BD898 which use the same pcb. If someone interested I also can post the input measurement circuit of Soldering iron to MCU and some temperature graphs of temperature control which I measured after some tests. They don't use linear control so is little tricky to calibrate the iron.
Also inside in soldering iron is used the J type thermocouple for temperature measurements. For best calibration I made little mod of mine station.

[sequence]

Hi,

I received a Yihua 939D a few weeks ago from an eBay vendor for $60 shipped:eBay auction: #360660367111

It supposedly has a 75w transformer, but I'm still waiting for some test tools to arrive in the mail. Other than a different iron holder and the Hakko rippoff yellow and blue colour scheme, I bet the only difference is the transformer and maybe different firmware. It's probably a good idea to replace the tip and heating element with Hakko ones, at least the iron lead has silicone insulation though. The soldering on the controller PCB looked OK to me, but I definitely plan to add a proper IEC power connector and a crimped transformer ground connector, and also remove the nasty flux residue. It has "temp" written as "tomp" on the BS heat recovery graph, but it definitely did the job when I was broke and needed a new iron. I'll post some pictures next week so we can do a comparison!

Hey. Only slightly off-topic but for those who are students/hobbyists (like me), a few months back a friend bought me the 937D Yihua soldering station -- which seems to be GREAT value for the price. It comes with 5 or 6 different tips and, at least for me, has been a great soldering station. It also came with a spare heating element, which is great. The tips are the same as a certain popular Hakko model so you can easily use the real Hakko quality ones. I'm going to check right now and see if my heating elements are Hakko as well...

Hmmm.. hard to tell. They have their specs printed on them but no company name. They feel good but with a heating tip who the hell can tell? More experienced eyes than mine, for sure.

showing the partially disassembled iron and the spare parts, spare heater on left
another shot of the same thing
Unit first switched on and showing 320 degress C
Unit starting to heat up to 320 degrees. Notice the heating light is on and it now shows 97 as it climbs towards 320
Cheap stand as mentioned in OP I jam extra tips and the scissor heatsink (which came with my old iron) into the holes around the edge... can't see any other purpose for those holes! I've never wetted the sponge as I have a steel wool cleaner (which you can see behind).

My impression of this unit (which cost around $55 CDN, delivered) is that while it may be a bit on the cheap side, it's done me very good so far. It goes waaaay beyond any temp setting I'd need. There is a similar version to the OP's that is black like mine but also has a heat gun. They also make a three-function one that has a built-in power supply!! I'd love to see THAT torn down, the power supply seems like a bit of an afterthought. Who knows though -- occasionally Chinese cheapies surprise me with their build quality.

If anyone is interested I can pop open my machine and take photos to compare.

[SquidgyB]

-snip-

Thanks mate, I managed to find the value (from low res pics on another thread in this site, and what was left of the printed value under the scorch marks) - it's a 120k jobby. I wired two 60k's in series and it's working fine now, though I've managed to break the glass reed switch on the heat gun while having a look around - I'll get another from Maplin tomorrow.

[abyrvalg]

Our workshop in Moscow was next door to a big dealer of this chinese stuff - Luckey/Aoyue/Net/Sunkko etc. We had two such dual soldering stations from them, customized with best available spare parts by their red-eyed repair man (that poor guy was working days and nights fixing that wonderful stuff, now I can see they started selling entire control PCBs for $10-15 as spare parts). I can say that hot air part was ok, but soldering irons were crap even after installing "original Hakko" heaters/tips - there was high heat resistanse between tip and heater (just try how easy the unscrewed tip falls off the heater - there is a big gap), resulting in tip sticking to big thermal masses (tip's heat capacity is enough for initial solder melting, but heat transfer is not enough to sustain the melting state), ugly "soviet" irons were more efficient

[DarthValentine]

Can anyone tell me what size fuse this thing takes? I pulled the old one out and the only thing I can read off it is 250v. The amperage is completely unreadable. Thanks for any help you can provide

[SquidgyB]

Mine was 13 Amp.

[DarthValentine]

Is yours a USA 110v version? or a 220v?

[SquidgyB]

220v European/UK (fuse was marked 13A 250V iirc)

[DarthValentine]

would it be the same fuse for a 110v version?

[Orpheus]

Turns out I have a US version  on my spares shelf (never got around to clearing space for the extra workstation after I did the teardown/check -- you know how life can be)

Mine has an F6AL250V (6A), which is what shipped from the warehouse.

Let me add that the plastic of the fuse cover is the softest I've ever seen in that application. Just removing it with a proper-sized Phillips chewed it up a bit -- and it wasn't even tight! Be gentle!

[sequence]

I can say that hot air part was ok, but soldering irons were crap even after installing "original Hakko" heaters/tips - there was high heat resistanse between tip and heater (just try how easy the unscrewed tip falls off the heater - there is a big gap), resulting in tip sticking to big thermal masses (tip's heat capacity is enough for initial solder melting, but heat transfer is not enough to sustain the melting state), ugly "soviet" irons were more efficient

It's wasteful, I wonder if oversized tolerance between the metal tip and ceramic heating element was caused by bad reverse engineering / supplied specs, or if the metal tips were manufactured without following the specs (bad machining). These cheap tips are made with inferior metal, but they would be good enough for most purposes if they were sized properly!

I've modified a real Hakko iron, and it's far more consistent and reliable. If a vendor sold tips that properly fit the cheap/counterfeit heating elements, I think they would make a lot of money!

[BravoV]

It's wasteful, I wonder if oversized tolerance between the metal tip and ceramic heating element was caused by bad reverse engineering / supplied specs, or if the metal tips were manufactured without following the specs (bad machining). These cheap tips are made with inferior metal, but they would be good enough for most purposes if they were sized properly!

I've modified a real Hakko iron, and it's far more consistent and reliable. If a vendor sold tips that properly fit the cheap/counterfeit heating elements, I think they would make a lot of money!

Assuming the base is cloned perfectly (which I doubt about it), you still need both "good" heating element and "good" tip in order to get proper temperature regulation and tip's heat recovery speed, check the discussions here :

-> Genuine vs fake Hakko heater.
-> Genuine vs fake Hakko tip

[sequence]

Assuming the base is cloned perfectly (which I doubt about it), you still need both "good" heating element and "good" tip in order to get proper temperature regulation and tip's heat recovery speed, check the discussions here :

-> Genuine vs fake Hakko heater.
-> Genuine vs fake Hakko tip

You're right, I worded that too simply. Nothing compares to a properly designed and built device, but if some of the obvious physical flaws were fixed, these cheap clones could be more suitable for basic household use. Buy something with a garbage solder joint? Fix it with a $30 soldering station. I meant for general purpose, mass-market, versus soldering irons that barely have electronics in them. It's too bad that Chinese clones of decent soldering stations/irons could burn a house to the ground, or cause people to end their electronics hobby. Just wait until standardisation is forced on these manufacturers, it'll be scary! No more fake "CE" cymbols, real standards for exported electrical appliances.

Thanks for the links though, I'll pay more attention.

[Orpheus]

Well, folks, I have a new failure mode for you:

A few weeks ago, I took my Yihua 898D+ (which had been torn down and tested on arrival, but never seriously used) off the shelf to check the fuse spec for another EEVblogger (a few posts back). I commented on how soft the plastic of the screw on plug was. Turns out it was cheaper than I knew.

I grabbed it today as I headed out the door to do a simple repair on my 2yo niece's favorite electronic stuffed animal, but when I got there, only the soldering iron worked. I figured it might be a magnetic switch issue in thr hot air handle holder, but when I got home, neither handle worked. The fuse checked out and a quick once-over of the internals revealed nothing wrong.

After several wasted minutes, I narrowed it down to the fuseholder itself, and sure enough, the inner thread of the fuseholder was a cheap thin piece of stamped nonferrous metal that has torn free of its solder tab by the simple act of unscrewing the fuse. On close examination, it appeared to have been partly nicked/cut, either by accident or as part of its manufacture, and tore the rest of the way when I removed/replaced the fuse. I don't know how common this will turn out to be.

It's simple enough matter to replace the fuse holder. I remain unconcerned, but I thought I'd let you know. Sometimes simple things like a failed fuseholder are hard to diagnose.

[rdkrco]

I observe that momentarily turning on the hot air switch and then immediately turning the hot air switch off causes the heating element to come on and continue to heat while the cooling fan blows. If all 898D stations behave this way, I would like to know why it was designed this way. The power to the heating element should be removed immediately when the hot air power switch is turned off.