Interesting 936 to T12 (FX951 Integrated Tip) conversion - Page 1
Forum section: electronics / general

author: nukie
author_rank: Frequent Contributor
timestamp: May 18, 2013, 01:48:30 am
content: While surfing around the worlds factory outlet, I found this interesting circuit mass produced that enables use of existing 24V Hakko 936 transformer or any 12-24V power supply, conversion for use of T12 tips. Have fun.http://item.taobao.com/item.htm?spm=2013.1.0.138.agHenG&id=14545897965

author: nukie
author_rank: Frequent Contributor
timestamp: May 18, 2013, 01:52:53 am
content: Smaller stillhttp://item.taobao.com/item.htm?spm=a1z10.5.w4002-711606001.11.hU0ut2&id=16080059650

author: nukie
author_rank: Frequent Contributor
timestamp: May 18, 2013, 01:55:18 am
content: Here's the screw neck for handle conversion if anyones interested.http://item.taobao.com/item.htm?spm=a1z10.3.w17-8334311666.19.ywtdIk&id=19506236998&

author: amyk
author_rank: Super Contributor
timestamp: May 18, 2013, 11:02:29 am
content: If I'm reading the schematic correctly it's an oscillator whose duty cycle is controlled by the thermocouple voltage... surprisingly simple circuit.

author: 001
author_rank: Super Contributor
timestamp: May 06, 2014, 12:01:40 pm
content: Hey Hey! Anybody tried this analog controllers for T12?Whether to proceed to the T12 instead 900/T18 tips?

author: dannyf
author_rank: Super Contributor
timestamp: May 06, 2014, 12:30:28 pm
content: It is not a converter - it is a miniaturized T12 controller integrated into the handle. The addition of the diodes prevents reverse voltage damages.QuoteIt is a proven design and many copies have been built. So yes, it will work.QuoteDepending on your definition of "oscillator".If the thermalcoupler's output is too low, U1A's output goes low -> U1B's output goes high, turning on the heater -> for a period controlled by R4/C2. After that, the heater is turned off, the temperature detection phase begins again.The diode on U1A does all the trick.If the

author: amyk
author_rank: Super Contributor
timestamp: May 06, 2014, 01:25:41 pm
content: Thanks for the explanation, it makes a lot of sense now. When the heater is on, the voltage across it is high enough to keep the U1A's output high. It senses the temperature while the heater is off.

author: 001
author_rank: Super Contributor
timestamp: May 06, 2014, 05:02:56 pm
content: It is theoretically good idea to use composite heater+tip…But is it REALLY T12 best then 900M/T18 tips? Any practics?Is it time to change 907/936 irons?P.S.: Some homemade AVR-based digital controller for T12 (schematics and firmware):http://radiokot.ru/forum/viewtopic.php?f=2&t=101844

author: dannyf
author_rank: Super Contributor
timestamp: May 06, 2014, 05:31:56 pm
content: QuoteDepending on what you mean by "best". T12 handles run much cooler - in fact, you can build a T12 handle out of a plastic pencil holder. Try that with a A1321 heater,. T12 is also much easier to replace.However, the heater is far more expensive than A1321/22, and more fragile as well.QuoteWay to complicated. You would need 2 adc pins (one to read the heater and one to read the pot to set target temperature), 1 to turn / off the mosfet. So a 8dip chip would be sufficient - I built a few with PIC12F675.

author: 001
author_rank: Super Contributor
timestamp: May 06, 2014, 08:14:07 pm
content: The project to which I refer is long story of A1321 controllerThis link is only adaptaition for T12 to save labor

author: dannyf
author_rank: Super Contributor
timestamp: May 06, 2014, 09:54:45 pm
content: I have no idea which one/ones you are referring to but the Russian site as well as the link from the OP are for a 2-wire heater core (aka T12-like). The A1321 is a 4/3-wire core with a ptc sensor.

author: 001
author_rank: Super Contributor
timestamp: May 07, 2014, 05:32:28 am
content: Quote from: dannyf on May 06, 2014, 09:54:45 pmAll right!The previous epic threads are:http://www.radiokot.ru/forum/viewtopic.php?f=25&t=2016http://www.radiokot.ru/forum/viewtopic.php?t=8505Interesting reverse-engineered Aoyue 2900 (T12 tips) with alternative firmware:http://radio.aliot.com.ua/?p=945

author: dannyf
author_rank: Super Contributor
timestamp: May 07, 2014, 10:03:26 am
content: That's another complicated design.

author: dannyf
author_rank: Super Contributor
timestamp: May 07, 2014, 10:52:36 am
content: It is fairly easy to drive a T12 handle using a 936 station: you just need to wire a high-common voltage range differential amplifier to the handle. Many times, a high-side current sense amplifier will do (50 - 100x for example).Driving a A1321 handle using a T12 controller can be done as well.

author: Sjaak
author_rank: Contributor
timestamp: November 10, 2014, 10:19:49 pm
content: Quote from: dannyf on May 06, 2014, 05:31:56 pmCould you provide a link to this project or give more info? I'm very interested in these tips as they seem to be fairy cheap on ebay.