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Topic: My HAKKO classic and T12/T15 soldering controller (Read 324718 times) previous topic - next topic

Re: My HAKKO classic and T12/T15 soldering controller

Reply #405 –
Can you measure the voltage on RB3 terminal with oscilloscope?

Re: My HAKKO classic and T12/T15 soldering controller

Reply #406 –
There is a 2v pk-pk 100hz half sine wave on that pin

Regards

Rob

Re: My HAKKO classic and T12/T15 soldering controller

Reply #407 –
OK I think it's the displays. There a load of activity on the pins but nothing on them

Rob

Re: My HAKKO classic and T12/T15 soldering controller

Reply #408 –
Has anyone found an equivalent to the sa39-11srwa led displays which I can't seem to find in the UK?

The CA ones I ordered from eBay ant pin compatible.

Any ideas guys?

Re: My HAKKO classic and T12/T15 soldering controller

Reply #409 –
It is SA36-11SRWA. I've just corrected it on the schematic.

Mouser, Digikey, Future Electronics, TME, Conrad have it.

Farnell has them also, with another color. The SA36 is the important part of the designation. The other characters are for the color and brightness.

For example,  SA36-11SURKWA is available at Farnell, which is even 3 times brightier then SRWA. If it is too bright, there is brightness option in the menu or you can replace the resistors with higher value.

Re: My HAKKO classic and T12/T15 soldering controller

Reply #410 –
[quote author="equalizor"]There is a 2v pk-pk 100hz half sine wave on that pin

Regards

Rob[/quote]

This is too low. What transformer are you using? If it is 24V, R30/R31 voltage divider makes it around 8V, and ZD4 limits it to arouns 3.7-3.9.

The comparator for the interrupt is set to 1.41V, and hysteresis is turned on.

It should work anyway, but the voltage on the pin is too low. Even with 12V transformer it should be considerably higher than 3V.

Re: My HAKKO classic and T12/T15 soldering controller

Reply #411 –
OK,  I'm pretty sure this thing is working.

I've desoldered the displays and as a test soldered a red led between common and one of the other display pins. When I press and hold various buttons the led changes state which in my mind means the pic is running to an extent. Should the speaker beep when any keys are pressed?

Rob

Re: My HAKKO classic and T12/T15 soldering controller

Reply #412 –
interesting, few pages back i had same problem. Next week i will change broken PIC and i try it again. Maybe bug in SW ? Can you look at SW sparkybg ? maybe mistake dot point or something.


Thanks

Re: My HAKKO classic and T12/T15 soldering controller

Reply #413 –
[quote author="mrjoda"]interesting, few pages back i had same problem. Next week i will change broken PIC and i try it again. Maybe bug in SW ? Can you look at SW sparkybg ? maybe mistake dot point or something.


Thanks[/quote]

I will try it, but I have a working prototype with the same firmware. So the probability for firmware problem is pretty low.

Re: My HAKKO classic and T12/T15 soldering controller

Reply #414 –
Hi sparkybg
How much is the max input voltage of T-12 tips? I'm using a 24V transformer and I want to use 24VAC to turn T12 tips on but it has a 24*1.414V= 34V peak value (1.414 is RMS). I'm worry if 34v peak value would harm it.

Re: My HAKKO classic and T12/T15 soldering controller

Reply #415 –
24V transformer is OK. The tip is a resistive device, so the RMS power/voltage/current matters, not the peak one.

The heater will withstand 24V RMS with almost any waveform as long as you hold it's temperature in control.

Remember - power to the heater is unfiltered rectified 24V AC. The RMS voltage is still the same (two diode drops lower) after rectification when there is no big enough filter capacitors after the rectifier.

Re: My HAKKO classic and T12/T15 soldering controller

Reply #416 –
Thanks. I have rectified 24V AC. a picture:



I have changed the supply to this transformed supply (because I thought the problem is my switching supply) but I still have problem with the amplifier. when I connect the input to GND, at output I have 0.3mv and when I connect the input to 3.3v(Vcc) I have an oscilated output between 20-18mv. :(

Re: My HAKKO classic and T12/T15 soldering controller

Reply #417 –
And how do you control the voltage to the heater? The measurements must be made while the controlling MOSFET is off. And it must turn off for a millisecond or so, between mains half periods.

Are you making my controller or something else? I cannot comment anything else. Everything in my controller has a purpose. If you removed something from your version I cannot know waht the conse`uences are, unless you provide a full schematic of everything behing the transformer.

Re: My HAKKO classic and T12/T15 soldering controller

Reply #418 –
No, currently I'm controlling it manually. I mean I connect +HEATER to rectified 24VAC and when it getting hot I disconnect it. several images of the circuit that I wired up:







This is my schematic:

Re: My HAKKO classic and T12/T15 soldering controller

Reply #419 –
the schematic is completely unreadable.

The only thing I can see is that you don't have 15V zener on the gate-source of the MOSFET. You will damage it this way.

Another thing - you are measuring microvolts using amplifier with large gain. You must either make good ground plane (I mean making a PCB), make special ground wiring, or you must make differential amplifier for the TC. You will always have trouble with circuits with high gain if you don't do the ground layout right.