I have a reflow station as well and the degree in electronics from Purdue to understand what happening. As I'm more interested in building my reputation, I will check them out for free until 1/1/18( not including shipping, limit five per customer). If I can find the problem and repair it that's free too( have the parts, free to send two get one 100% working. I will even start posting my repairs to YouTube(like my hero ipad rehab, lol). As a newbie I am only allowed to PMs, please text me at 219.525.7771
I have heard about this chain of people speaking of and I just don't see how it can exist functionally .If the chain is as one described like a ladder then one going out will not affect the voltage of any others, as the voltage drop in a parallel circuit is equal regardless of the number of elements if it is in fact a like a steel chain then the first time one goes out they should all instantly stop working. So I'm very look interested to look into this.
Thanks,
J
They're series.
You should research a bit more before attempting to repair these.
I suppose if they are series(as logic ICs should NEVER be) and they are shorting to ground you're going to get a lot of burnt connectors and I am seeing a lot of those here and on eBay. But slowly going out one by one that has to be completely unrelated to power delivery, unless it's the power supply is sending noisy power then there is no causal relationship between the first going out and any others, they are just all the symptom of the one continuous PWS malfunction. One other option , and that one is causal , when the first chip goes out it doesn't truly die it just goes insane, sending spurious signals throughout the whole power bus killing the others one by one (haha, I should call this the zombie theory ). Since you think I should do some more research maybe you could point me to the data sheets or maybe the schematics, lol thats funny.