Looking for Yihua 936 clone a1321 mods - Page 1
Forum section: electronics / beginners

author: xnotx
author_rank: Contributor
timestamp: December 31, 2017, 11:07:16 pm
content: Has anyone modded aYihua 936to work with the better ceramica1321heater?

author: xavier60
author_rank: Super Contributor
timestamp: January 01, 2018, 02:21:42 am
content: You have possibly seen this?https://www.banggood.com/Soldering-Iron-Station-Control-Board-Controller-Thermostat-A1321-for-936-Soldering-Station-p-1180489.html?rmmds=detail-left-hotproducts&cur_warehouse=CN

author: xnotx
author_rank: Contributor
timestamp: January 01, 2018, 01:55:17 pm
content: I have seen those, ty. Those are a last resort lolI "feel" like this needs to supply more current with the higher resistance on the new heater, so been reading and watching and learning.Will then move to target differential voltage for the 2n3906/bt137, so it shuts off. (I think)I'm not "new" new to electronics, just the inner workings of components, how they are controlled, what they do, etc etc.So I think this will be a fun learning processes.I don't have a specific to this model schematic, but do have two "similar" ones I've been going over.EDITThat board you linked for the a1321 is nearly identical, lm358 and bt137.

author: phil from seattle
author_rank: Super Contributor
timestamp: January 01, 2018, 07:27:00 pm
content: Maybe you just misspoke but you can't "supply more current with the higher resistance". Ohms law. Higher resistance means lower current. And, you don't supply current, the device draws it based on ohms law. You can increase current by increasing voltage or reducing resistance. Again, by ohms laws.V=IR, not just a good idea, it's the law.

author: xavier60
author_rank: Super Contributor
timestamp: January 01, 2018, 09:44:14 pm
content: Quote from: xnotx on December 31, 2017, 11:07:16 pmTo be certain, are you trying to convert from the type of heater that has the thermocouple sensor.

author: xnotx
author_rank: Contributor
timestamp: January 01, 2018, 10:38:29 pm
content: Quote from: phil from seattle on January 01, 2018, 07:27:00 pmDefinitely mis-spoke, rocking a nasty cold lol.The a1321 heater element is of higher resistance.Quote from: xavier60 on January 01, 2018, 09:44:14 pmCorrect.Looking at the "a1321 compatible" board on banggood/ebay. These are pretty much identical, so I know it can be fixed to work good with the a1321, I just lack any formal training.I need a new multimeter though, my old one is unreliable and new one does wonky stuff when I put it on AC.With this cold, i'm wiped and don't feel like looking up resistor band markings off a picture to reverse engineer the boards from banggood/ebay.I've watched many op amp videos but things are not sinking in, so time to put it aside until I feel better.EDIT:So basically what the issue is, is that the heater circuit is always on, LED is always on, tip gets warm but not hot enough.I think the tip is getting about 1.x volt, which seems really low.(could be my multimeter)

author: xavier60
author_rank: Super Contributor
timestamp: January 01, 2018, 11:58:47 pm
content: I wouldn't expect the A1321 heater element to be higher resistance. The PTC thermistor is about 50\$\Omega\$ at normal ambient temperature.