EEVblog #242 - Hakko FX-888 Soldering Iron Hack

[therealjammit]

My solution would be to build a circuit pretty much just like yours, except of an n-mosfet I would use another resistor. The bi-color would be hooked up to the resistive divider at about 4.5V. The transistor in the chip would either short to GND to turn on one LED, or let it float to 9V to turn the other LED on. The resistive divider values may have to be adjusted a little to give both LED's an even brightness.

[mccunecp]

NICE now if you think of it when you increase the temp you now know when the temp is reached cool video.

[DO5TMX]

Glad to see the quality of your raw footage (lighting, audio, etc.) has constantly improved but in the last few videos I noticed ugly, dropout-style artifacts on some cuts.

What's up with that? o_0

[EEVblog]

@DO5TMX I've switched to a new video editor, NCH VideoPad, I think it has a few glitches...

[joshstube]

LOVE the MODS!

More MODS please!

[ThinkLearnSolve]

"that will be good enough for Australia", hahahaha

[ThinkLearnSolve]

@ThinkLearnSolve P.S. my favorite youtube channel :D

[rampike74]

This sod knows what he's doing. :-D

[squiggyreck]

Dave I love these types of videos. Real Wrld Problem and Answer and even a little fail until you added the Capicator..Thanks

[amtpdb1]

Hi:

Great idea! Could you show how to do this on maybe a stahl cheap soldering station? Mine has a light for on and off, but I like the idea of one telling you when it is heating so that you know when it is up to heat. That way if it is not hot enough and the light is off, you know to turn it up instead of waiting thinking it is not up to temp.

Thanks again for the great videos.

Don

[bytebender]

@amtpdb1 hi, on my cheap iron I just added led & resistor parallel to the soldering iron output socket - the led lights up the whole time if the iron is heating up and flashes if it holds the temperature, just like the expensive Weller soldering stations. This works 'cause the soldering station does low frequency (0.5...1 Hz) pwm to control the output power.

[amtpdb1]

@bytebender

Thanks for the information. I will have to open it up and see if I can do as you mentioned. I think I understand how you did it.

Thanks again.

[DjRaveKing]

Hey dave , i have a review on a updated version of a 936 . It now has a permanent power on LED and it triggers on every 1/2 sec .

[queazocotal]

No transistor solution?

Take the open collector output, 470R to +9V.

Wire this to one side of the LED.

Two 220R resistors between 9V and gnd, to provide a 4.5V virtual supply are connected to the other.

(adjust 220 values to get equal brightness of LED)

Output on - current flows through the LED one way to the virtual ground.

[zeniltogf]

Brother you are beast at it, great job, really like your videos.

Continue to post more videos

Here in Brazil many watch your channel especially my colleagues who work with electronic

hugs

[ortseamym]

Absolutely brilliant! Can't wait to tear into my 888!

[FPPVideoProductions]

Epic idea. I lost a soldering iron tip to oxidation because I didn't see the LED was blinking. The tip was exposed to possibly a continuous week of heat and was oxidized to all hell.

[sterwing]

Bingo!

[Albinorama]

Genius!

I have a FX-888 120v and I would to use it with 220v.....

[CampKohler]

Instead of turning it off by hand, why not make it foolproof? Install a solid state timer that will turn it off automatically. You could have two buttons on top that will turn on the iron for say, 5 mins and 60 mins; you push the one you expect to need. At the end of the cycle, a beeper sounds for 5 seconds to remind you to push a button once more, else it shuts off. Then you never have to worry about it. Pick off xfrmr low voltage to run the circuit. Note: One button pole also boots xfrmr on,

[gryzman]

beauty !

[Tim3492]

Thank you for your awesome videos!

[fingerboy18]

Swedish colors haha! I rather like that combination of colors.

[koktelici]

Hey Dave, I would appreciate if you tell me where can I order 220 V version like yours because

e-bay has only 120 V ones.

It looks like that transformer can be adjusted to both 120 and 220V if I saw it right. Can you confirm that.

[EEVblog]

@koktelici Farnell stock it in Oz. No, I don't believe it is tapped, just the top PCB is designed to fit different transformers.

[koktelici]

@EEVblog thx

[widar28]

lol "No hack is complete without hot snot" xD

[BulletMagnet83]

@widar28 I'm going to refer to it as "hot snot" forever now!

[aptsys]

@neuraxon77 Think about it - you just shorted the bi-colour LED.

[neuraxon77]

@aptsys Maybe I wasn't clear. The positive rail goes into two resistors with one going to either side of the bi-colour LED (two photodiodes) in Dave's drawing at the very end of the vid. All I'm doing is replacing the two with one and connecting that to either side of the bi-colour LED.

[aptsys]

@neuraxon77 Yes, this would short out the LED. A bi-colour LED only has two legs - if you connect them both together, it'll never work.

[dalriada842]

@neuraxon77 The bi-colour LED he is using is a two pin device. There is no way to separate the anode and cathode from the two internal LEDs. By only using one resistor, both anodes and cathodes would always be at the same potential, and therefore off.

[raguaviva]

I love it fun to see and I learnt things I can actually use!

[zaprodk]

Love the elegant solution - Most people today would just throw a micro at the problem, maybe even an Arduino :-O

[SajjadBro]

You could have used the scope at the first time but i guess you intentionally didn't.

[tynemouthsw]

As an alternative, how about a more readily available common cathode tri-colour LED? Single transistor to invert the output to drive the red side and just a resistor on the green side so it is always on. Green = on, Orange = heating?

[kageofkonoha]

Great mod. I saw something similar (not the LED just your purpose) to this last year using just an AtTiny85 that would shutoff the Iron with no activity after a set period of time.

[philbx1]

Hmm, looks like there might be a bit of room in the top.

Maybe enough space for a clothes-dryer timer switch?

[keenantims]

Love the idea, and your solution is very elegant - nice to see the design process. It's the one thing I dislike about my Hakko 936. I might just do the simple power LED mod, now that you've given me the idea to bother, normally it bugs me while I'm on my way out the door and can't remember if I turned it off or not.

I think @kevtris is probably right though. Tried to link you to the 936 schem but YouTube is being a pain.

[EEVblog]

@keenantims Yes, I see the 936 schematic now. The FX888 uses a bigger pin count chip. Perhaps it's still doing something weird with the LED, I didn't trace that far.

[EEVblog]

@keenantims Just looked at the 936 schematic. Yes, that's rather tricky.

The FX-888 uses a single bigger pin count device, so who knows what it's doing with the LED? Is it just a consolidation of the existing design into the one chip, or something new?

[Bokononistly]

I love your catch phrases. "That's good enough for Australia!" "Bob's your uncle"

[rng8891]

You want to have an LED tell you when the Iron is on or in a "Low Heat Mode"? One word... PACE. Oh yea, that's right, I said it. The older units used to have the LED's go out when cooling, but I think the newer units have the LED on all the time.

How about a Tri-Color LED? The colors would be Green (Good) - Operating with Tip up to Temp. Yellow (Indicator) - Tip Temp is lowered to prevent damage. Red (Warning) - No Tip is detected. Or is that just duplicating a PACE?

[jjoeygold]

I've used LinearTech's LTSpice - free spice software to to model similar circuits. Perhaps I am lazy and don't want get out the bread board. There's a 34,000 member forum with Many additional 1000's of models tech.groups.yahoo.com/group/LT­spice/ . many Tutorial on youtube

Joe

[shmore]

Love these new videos

[Comptekhs]

I noticed that LED lighting up green when using the volt meter or was that just ceiling light hitting it?

[randomgarfield]

@Comptekhs he was using the 'diode test' mode of the multimeter to power the LED. Not all meters can do it.

[Ryantron9000]

nice mod Dave. I might have to do that to mine.

[kevtris]

Just saw the flickering problem on the LED addition. If it works like the older hakko 926 and 936, then the LED is actually part of the hysteresis on the heater controller. This is why the LED lights up very dimly when the heater is off (you can see it in a darkened room). I think it does not like the direct pullup to 9V and needs the LED drop to work right.

Sounds like the 888 might be using the same chip (though you mentioned it was hakko branded? maybe they have it made for 'em now)

[kevtris]

here in the US, the three leaded LEDs are extremely common, except they are all common cathode.  Common anode versions exist but they are extremely rare and might be custom.

[EEVblog]

@kevtris I couldn't find any common anode red/green or RGB LED's in Australia.

[aquaajb]

@EEVblog NO RGB? That sucks man. I'll mail you a couple!

[GitarStu]

@EEVblog ebay has common anode RGB LEDs. They have 4 LEDs - Anode, Green, Red, Blue. A packet of 10 is around $7 delivered.

[AntiProtonBoy]

LEDs FTW!

[Maxxarcade]

I have the 936-12, and the LED is just like this one. I've thought about doing this hack as well.

[kiyotewolf]

This was really a delightful video. I love LED's, and your elegant one on, one off circuit, was great.

[superdau]

Had I known of the "PWM" before, I'd definitely gone for an NE555 as retriggerable monoflop. I got over 100 of them for very cheap a time ago. You know how versatile they are ;)

Since it's output can source and sink, I'd have gone for two SMD LEDs close together to make my own two color LED. Shouldn't be much larger the the 555 itself in dead bug style.

[ixamraxi]

I think my favorite part about this video was that you stressed the how and why you had the resistors and couldnt get rid of them without changing components. Thanks for taking the time to make the video!

[LapsusAntepedis]

Hey Dave, absolutely love your videos! At around the 2:53 mark you mention that you've done a teardown of the Hakko FX-888, but I can't find it on your channel anywhere. Was it on the forums, or is it one of your private or deleted videos that occasionally pop up in your playlists? I'd love to see it.

[EEVblog]

@LapsusAntepedis It was part of a live show, don't recall which one. Wasn't a normal teardown video. I don't have any private or deleted video. I've never put up a video and then permanently removed it.

[CampKohler]

@EEVblog So this means you're going to put the drive-time rant back up?

[valajbeg]

great, it was not only up to hack, you told much wider story :) THANK YOU

[valajbeg]

GREAT :D

[skierplaterandy]

I use a 30 watt iron and a variable power supply which has an ac output

[ivaneduardo747]

I can't mod my Hakko because I don't have another good soldering iron. It's soldering irony.

[schmatzler]

I have a Rothenberger 30W and it seems to operate in the same way. Could apply this "hack" on it also...maybe. (:

[gamozodawtorg]

I actually left mine on all night a while back. Luckily, there were no issues, it still performs like it's brand new.

[1ebutuoy2]

I do have an uncle named Bob but I've never found that to be a good thing...

[ForViewingOnly]

Not an electronics question, but how do you choose the type of glue when sticking two materials together? I was going to buy a hot glue gun, but then I read that it doesn't work with all plastics. Are adhesives a complex science or is there one glue product that works every time for all materials? I'm a glue dummy.

[deathventure]

@ForViewingOnly all depends on the application. Hot melt glue won't work as well on smooth plastics. There's various grades of adhesives and epoxies though so you're not without a solution.

[ivaneduardo747]

Why not using a low side NPN transistor on the low side? The stock 2k2 resistor can work as the base resistor.

[ivaneduardo747]

@ivaneduardo747 @ivaneduardo747 Actually, ignore that comment. The red LED could still shine that way. The best way to keep it simple is todo what @mikeselectricstuff suggests.

[heyhey1385]

common anode rgb leds are common you could have cut one lead

[randomgarfield]

@eevblog unwittingly sets off a global spate of electrocutions in the hobby community. ;)

[EEVblog]

@randomgarfield Darwin doing his job!

[donpalmera]

Why do people say Hekko when it's spelled Hakko? never understood that. Hakko stuff is good, but expensive :(.

[EEVblog]

@donpalmera I pronounce it "Hay-Ko"

[donpalmera]

@EEVblog in Japanese that is Hekko :)

[laharl2k]

@EEVblog but it's in japanese, so it's pronounced "Ha" (as in hack) Co (as in Colt) :P

[deathventure]

@donpalmera It's actually reasonably priced compared to other solder systems.

[donpalmera]

@deathventure Well, comparatively expensive, Hakko's little fixed irons are cheap i.e. around about 1000 yen for a bog standard iron. Their temp controlled irons and stations are a lot more than that (and so are other brands) and they hardly ever turn up on the used market here at least. In Japan at least there are slightly cheaper brands that are around the same level of quality.

[psycholoner]

@donpalmera It looks like the company originated (or is from) Japan, so that should be romaji. If it is, its pronounced "ha-kkoh". I never pronounce it like that myself though. Whatever you're comfortable with. I have a feeling that a while back I saw a video on their site where they pronounced it in a completely different way too.

[donpalmera]

@psycholoner The name of the company is .. deep breath .. hakkou kabushikigaisha (白光株式会社). I operate in Japanese 90% of the day (the interwebs is the only place I use English now) so it sounds weird to me. heh

[scompo]

neat!

[randomgarfield]

@mikeselectricstuff the second resistor is probably what I'll do. Much simpler and no glue required. Or I could go all out and add a tiny 6 lead PIC10F206 as a pulse stretcher and use an RGB LED. :) The second resistors is probably what I'll do.

[EEVblog]

@randomgarfield But you don't get the joy of a different colour LED!

[randomgarfield]

@EEVblog LOL indeed. Surprised you didn't find a way to use an Arduino to do it, would do wonders for your video rankings. =)

[TheSurvivalSecrets]

Great video David. I am learning new things from you constantly such as learning about the mosfet today. Keep up the great work.

[EEVblog]

@mikeselectricstuff I've tried that LED/GREEN parallel thing, it didn't work. Green still stays on, but weaker. Entirely dependent upon the particular LED characteristic curves.

Yes, the "dim" mode would be the easiest mod to do.

[Zed1967]

Dave, I don't know if you are a fan of the cult UK science fiction comedy Red Dwarf but this reminds me of a line Kryten says to Rimmer about stepping up to red alert. ''Sir, are you absolutely sure? It does mean changing the bulb.'' lmao XD

''Dave are you absolutely sure you want a green LED for power on and a red LED for heat on? It does mean changing the LED.''

The simplest solutions are usually the best. Love your channel man (EEVblog <3)

[rainbowsalads]

hi , i wonder what is the glue you used? i have leds in a unit that fall out on occasion, be great to get some of that stuff.  btw Nice hack and solder job, must have a very steady hand for that.

[Superfungus0]

Cool Hack! Are you worried at all about that micro pin sinking about 4x the current it was previously?

[EEVblog]

@Superfungus0 It's less than 20mA. Any open collector output that can't handle that ain't worth a pinch of shit. So no, not the least bit worried.

[Superfungus0]

@EEVblog Haha fair enough. Not that it matters, but I'm curious: did you ever verify that it was open collector and not a regular I/O (low and HiZ vs low and high)? Seems like the two would behave identically until you unloaded that pin and 'scoped it. Or were you able to see a rising edge time constant or something with it all hooked up that showed it was open collector?

[blueblast88]

this seems like it will work with my hakko 936 it has the same light "feature" and i dont like it so thanks!

[heroineworshipper]

There's always looking at the power switch instead of the LED to see if it's on.  You really need a thyrister that flashes the room lights when you leave & the iron is still on.

[EEVblog]

@heroineworshipper Nope, the power switch is on the right side, against the wall, hard to see.

[89rafa]

the blue led is red and the red led is green.

Love your videos.

[kiyotewolf]

I would love to get one of your little power supplies in the future, the one you're developing still, and to get it signed by the great DaveCAD Jones.. yeah!

[oapeland]

how about a 15-30 minute timer on the main socket.. cheap and easy :)

[TerminalJack505]

Hmmm. Considering that this is Hakko's replacement for the 936 station I'm surprised that it doesn't turn itself off automatically after two hours like the 936. I guess I'm glad I got the 936 instead since I'm pretty paranoid about forgetting and leaving it on.

Also, I don't like that the 888 isn't stackable like the 936. I actually have a second station (some knock-off brand) that uses the same style of case sitting on top of my Hakko 936 so that feature saves me some bench top space.

[EEVblog]

@TerminalJack505 Since when has the 936 had an auto turn-off feature?? I never likes the stacking thing, always felt too uneasy doing it, but I can see how some might miss that.

[TerminalJack505]

@EEVblog Oh, great! Now I'm going to be really paranoid. LOL.

You're right (of course.) I just looked at the manual and apparently it doesn't have that feature. Maybe it's the knock-off brand or my hot air station. Who knows?

Great video. I know that I learned something at least.

[TwoToBeamUp]

Very interesting video.

Really odd that PWM was used to simply operate a LED...

"Hot snot" :o) That's a good one. Great stuff that.

What happened to your drive-to-work blog? I went to watch the last 10 minutes and it's gone?

Did you talk about the Aussie cricket team at all?

[EEVblog]

@TwoToBeamUp Well, it's not actually PWM as such, just likely the direct output from the heater switcher which will be pretty random.

[SigEpBlue]

Blue & yellow (technically maize, I guess) are Michigan colors, so it suits me just fine. Maybe Hakko are Michigan fans, too. :)

Actually, the FX-888 LED behavior is one of the primary reasons I decided to install a separate electrical system on my work bench. Now I have a bright green neon lamp any time the system is turned on; I think almost every lab at my old university was set up that way too, with the mains power on a key switch.

I still hate the FX-888's switch location!

[dylanpalmediy]

I'll have to grab me one of these soldering stations. I got my Amprobe AM-220 from your recommendation, and I love it, so hopefully I'll love this one too!

[jmpattillo]

Hi Dave, aren't you worried about exceeding the maximum current on the IC pin since you lowered the value of the resistors current will be flowing through both resistors when the IC pin goes low?

[EEVblog]

@jmpattillo It's less than 20mA. Any open collector output that can't handle that ain't worth a pinch of shit. So no, not the least bit worried.

[MrDubje]

Thats why i have a weller wsd 81. Auto sleep mode. ;)

[EEVblog]

@MrDubje That's too much technology for a humble soldering iron...

[avalon449]

Dave, what happened to your last vid, the vblog? Why did you remove???

[dylanpalmediy]

@avalon449 It was a reupload. I'm guessing that's why.

[EEVblog]

@avalon449 It was a Youtube screw-up, it's an old video.

[Fangornmmc]

Artistic? yellow and blue? Yuck! No offense though, I am one of the most noobish electronic hobbyists you'll ever meet so no reason to take me seriously ;)

[EEVblog]

@Fangornmmc I thought that at first glance too, but then came to rather like the colours, it complements the blue colour rubber work mats nicely!

[samgab]

@EEVblog Yeah, before I bought my FX-888, from pictures I thought it looked somehow ...juvenile, like a toy. But in person, it's amazingly well build, and solid. The toy-like appearance just dissipates once you actually handle one. It exudes quality, even down to details like the high quality soft bendy silicone cable that goes to the iron itself. And the colours are neither here nor there. At least it doesn't have fancy (flame?) graphics like some of the versions of it they released...

[PanzerschrekIII]

Great, I had ideas too for mine, but I never really tried it, I know how to do it now :p