JBC AD2200 Soldering Station

[wblock]

Hello!  I've been lucky enough to obtain a used, not-quite-working JBC AD2200 "Version 2.1" soldering station with a 2245 handpiece.  It heats, and the station makes no complaints.  The LEDs show that it detects when the iron is in the stand, when it goes to sleep, and when the handpiece is not attached.

The problem is that while it heats up enough to barely hiss on a wet sponge, it does not get hot enough to melt any solder.  Turning the knob makes no difference as far as I can tell.
There is no obvious damage to anything, internal or external.  When the iron is lifted, the green "ready" LED comes on immediately, as if the set temperature is the same as the sleep temperature.

My first guess is the main temperature pot.  It is a Piher, with a tiny label that says 10KA91104.

There are three CapXon electrolytic capacitors, which my homemade analog ESR meter says are "meh", but I doubt one of them failing would produce these symptoms.

I can post measurements and photos later, if the forum software will allow it for a new user.

Can anyone point me to schematics for this unit?  Searching the web found nothing, not even any failure reports.

Thanks!

[wblock]

Some photos:

[GreyWoolfe]

Try replacing the CrapXon caps.  Those have to be the worst in existence.  It just might bring the iron back to life.  I couldn't find anything regarding a schematic, but if they're smoothing caps, you may be getting too much ripple into the circuit, disrupting proper operation.  It certainly couldn't hurt and if you can sort out any other possible problems, you know the caps will last.

[wblock]

True, although I would expect ripple to cause random problems, or at random times.  The difficulty with replacing them right now is that this iron was supposed to be the replacement to my Aoyue 2900, which has never been great, or even good, but finally became unable to hold a temperature at all a while back.  It does enthusiastically shriek about how it fails to hold a temperature, though.   A couple of attiny 4313s are on order for a brain change and firmware replacement.

In the meantime, I'll see if I can find out what ESR values those CapXons claim to have, and find replacements.

Edit:

For reference, the CapXon capacitors are:
470uF @ 50V, 13x21mm, 5mm lead spacing, GS series, spec sheet says 858mA ripple
220uF @ 16V, 8x12.5mm, 3.5mm lead spacing, the label says "SSL+", but no data sheets
Blocked by heatsink, but I think it is 100uF, definitely @ 50V, 8x12.5mm, 3.5mm lead spacing, GR series, spec sheet claims 286mA ripple!

[GreyWoolfe]

Is it safe to assume that you already checked the pot with a DMM-min/max readings and linearity?  What about  the possibility of a worn out tip that just won't heat up?  It might be worth getting a cheap 936 clone to fix the JBC.

[wblock]

Yes.  Well, I tried to check the pot, but it appeared to be in parallel with other stuff, including capacitors.  Hence the desire for a schematic.  Or the conductor or wiper might be broken.  And of course the best way to check it would be to unsolder it and measure it out of circuit...

[nanofrog]

What about  the possibility of a worn out tip that just won't heat up?

This would have been the first thing I'd have tried to determine. 

Certainly the easiest thing to test (don't even have to open the power unit), and a known working tip is required. 

Maybe fix the Aoyue first (use a firestick), then use that to fix the JBC (assumes the parts on order will fix it).  Thinking lowest possible repair cost at any rate (OP may even posses a suitable firestick, placing the necessary equipment cost = zero  ).

Besides, 3x soldering stations makes the poor guy look like an addict (2 stations + 1 firestick is the max acceptable limit). 

[wblock]

Sorry, I did ohm out the tip, but forgot to post it.

If it looks like:   <--------1--------|--2--|--3--

3.5 ohms between 1 and 2, 3.0 ohms between 2 and 3, and 0.3 ohms between 1 and 3.  (Fluke 79II meter.)  What do these tips do when they fail?  Visually, this one looks very good, no plating problems.

I (gently) cleaned the tip contacts with a dry plastic scrubbing pad, but it made no difference.  The station detects it, and the cable appears to be continuous.

Two (working) irons is probably enough, so when one breaks there is a way to fix it.  Two broken irons is the same as none at all.

[GreyWoolfe]

Something seems to be wrong with that pot.  Looking at the part # of the pot, makes me think it might be 10K.  I would remove it and bodge in a 10K linear pot just to see what happens.

[wblock]

Certainly the easiest thing to test (don't even have to open the power unit), and a known working tip is required. 

A new tip is on the way, should have it on Monday.

Maybe fix the Aoyue first (use a firestick), then use that to fix the JBC (assumes the parts on order will fix it).  Thinking lowest possible repair cost at any rate (OP may even posses a suitable firestick, placing the necessary equipment cost = zero  ).

This motivated me to take apart the Aoyue 2900 again.  This time, I looked at the control board.  It also has caps with ridiculously optimistic ratings, ones so bad that CapXon would be a huge step up.  Replacing them with only an 80W uncontrolled American Beauty that would be better suited to soldering railroad rails together was... challenging.  Mistakes were made, pads were lifted, in the end I replaced all of the terrible caps.  Initial tests were good, then I turned up the heat and it went nuts again.  It loses the temperature and then oscillates wildly, like 430...278...434...318, beeping loudly to remind you how badly you failed in buying it.  It never recovers, has to be power cycled.  This one used to not be that bad.  Others have reported the same problems, due to some bug in the firmware.  Might be this one had something else fail and that just points out the bad firmware.

The abysmal quality of the Aoyue is a good example of how reviews on the net have to be scaled based on the reviewer.

Besides, 3x soldering stations makes the poor guy look like an addict (2 stations + 1 firestick is the max acceptable limit). 

"...And over here is my collection of broken soldering stations."
"Could they be fixed?"
"Sure, I guess, but why would anybody collect those?"

[nanofrog]

A new tip is on the way, should have it on Monday.

This motivated me to take apart the Aoyue 2900 again.  This time, I looked at the control board.  It also has caps with ridiculously optimistic ratings, ones so bad that CapXon would be a huge step up.  Replacing them with only an 80W uncontrolled American Beauty that would be better suited to soldering railroad rails together was... challenging.  Mistakes were made, pads were lifted, in the end I replaced all of the terrible caps.  Initial tests were good, then I turned up the heat and it went nuts again.  It loses the temperature and then oscillates wildly, like 430...278...434...318, beeping loudly to remind you how badly you failed in buying it.  It never recovers, has to be power cycled.  This one used to not be that bad.  Others have reported the same problems, due to some bug in the firmware.  Might be this one had something else fail and that just points out the bad firmware.

The abysmal quality of the Aoyue is a good example of how reviews on the net have to be scaled based on the reviewer.

I recall reading something about this. Sorry you got landed with one of the affected units.  I do hope you get it sorted well enough to fix the JBC (i.e. can hold a set temp of ~300-325C). 

FWIW, Quick is the only Chinese brand I've any confidence in, which was the result of wraper posting photos of the internals of his 861DS (I purchased an 861DW; other than the transformer, they're the same unit). Do note it's not a "cheap as chips" brand however. And hot air is about the only product I'm willing to recommend going Chinese, as the name brand products are just too expensive for hobbyists IMHO (~$700 to start). My preheater (hot air type) is also Chinese. No where near the same quality as Quick, but it was the only 120V unit I could find (Tenma brand). Desolder would depend on your location, but the Hakko FR-300 is priced well enough to compete with Chinese desolder stations IMHO.

As per the reviews, you definitely have to be careful/take it with a grain of salt. I like corroboration, but particularly like reviews that the poster had some real time with the unit. Not just an initial impression, but updated with longer term information (particularly if the unit craps itself), as it's far more useful. EEVBlog helps (vs. just Amazon for example), but can only go so far as well. So even with due diligence (research), you may still be making a genuine gamble (not enough reviews, paid reviews to skew the ratings, ...).

"...And over here is my collection of broken soldering stations."
"Could they be fixed?"
"Sure, I guess, but why would anybody collect those?"

Enjoy fixing them, but then either sell them off or make a donation to a Hackerspace, individuals you know have entered electronics,... Heck, run a contest & give them away as prizes.  This way you don't appear to be an addict. 

[wblock]

Update: found a 40W element for the American Beauty, which actually makes it usable.  Then removed the solder from the dozen or so worst-looking joints on the Aoyue power board and resoldered them.  Then checked the cable, cleaned contacts again, and finally tried it again with multiple tips.  And it works!  The problem appears to have been a combination of the power board and the best chisel tip.  Maybe the heater in that tip is failing, increasing in resistance or has a crack that makes it intermittent.

So, back to business.  Yes, the pot in the AD2200 is 10K.  It's a kind of strange mounting, eyelets on the pot soldered onto headers on the board.  After removal, the pot measures fine and seems to not have any failing ranges.  Photos:

[wblock]

Update:

Replaced the capacitors, resoldered the pot, and put it all back together.  This did not change the symptoms, it still warms up but not enough to melt solder.  As far as the LEDs, it seems to be operating fine.

Today, tried it with a new C245-905 tip, and it does the same thing.

Interestingly, there are no trim pots anywhere in this thing.  JBC claims that the microprocessor control makes calibration unnecessary.  I don't see how that can work on a variable-temperature iron, particularly with variation in the manufacture of individual tips.

[nanofrog]

Update:

Replaced the capacitors, resoldered the pot, and put it all back together.  This did not change the symptoms, it still warms up but not enough to melt solder.  As far as the LEDs, it seems to be operating fine.

Today, tried it with a new C245-905 tip, and it does the same thing.

Interestingly, there are no trim pots anywhere in this thing.  JBC claims that the microprocessor control makes calibration unnecessary.  I don't see how that can work on a variable-temperature iron, particularly with variation in the manufacture of individual tips.

I'd check the feedback loop circuit next (work your way backward).

[wblock]

Thanks to help from JBC USA, the problem turned out to be the handpiece.  With a different handpiece, both the tips and base work fine.  The handpiece appears to be molded around the contacts, so it's difficult to take apart non-destructively.  The only way I can think of this problem happening is from flexing of the cable breaking most but not all of the wire strands to the tip heater, with the high resistance preventing enough power getting to the tip.  But it seems like the base would not show the "ready" light because the tip never gets up to heat.

[GreyWoolfe]

Good to hear that you finally got that resolved.  I hope you get many years of enjoyment out of the JBC.

[nanofrog]

Good to hear that you finally got that resolved.  I hope you get many years of enjoyment out of the JBC.

+1 

[NortliW]

Please Help!

Got this AD2000 station and trying to get it to work with the new T245 hand piece but I do not succeed. I have the same symptoms as described above with the iron not warming up enough. The station is working and I can see the output of about 30Vpp max pulsed but it does not drive the iron enough. Soldering tip is C245. I got it hooked up correctly with TC+(red) to pin 2, heater+(blue) to pin 5+6 GND (green) to pin 1 of the station.

Any ideas welcome.

[nanofrog]

I don't know the pin out, but double check.

Are you sure the station is truly working rather than an erroneous output?
What about the cartridge itself? New? Old?

I can't find a schematic, so it looks like you'll have to contact JBC for help on that (or reverse engineer it; should be simple enough, as I suspect it's just a single sided board).

[NortliW]

Hi,

brand new tip also used another new one, I can see the pulses from the controller, it controls but output is not enough to heat the thing. JBC did advice me not not use the two together.......AD2000 and T245. But some people got it working so I thought what the heck.

Will add later what's on the scope. TNX!

[nanofrog]

Hi,

brand new tip also used another new one, I can see the pulses from the controller, it controls but output is not enough to heat the thing. JBC did advice me not not use the two together.......AD2000 and T245. But some people got it working so I thought what the heck.

Will add later what's on the scope. TNX!

The pin-outs are probably different, and they had to hack the female connector's pcb connections. So I'd go back and find those that have done this, and get the details. 

After all, in side the handle are just the necessary connectors to make contact with the cartridge. Also, this may seem silly, but make sure it's inserted fully (new handle's contacts are stiff).

Good luck. 

[NortliW]

This is what the output looks like.....