HF Start Killed Pro V Lens?!

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I'm not entirely sure what happened in the last hour...but from what it looks like I think the HF start on the tig might very well have killed the PCB inside my Pro V lens I noticed it the other day when it would occasionally shut itself off during the arc start. I tossed it up to batteries going bad for the day as I've seen that behavior before.Put in fresh cells today to finish up this robot chassis and it started doing the same thing. Work is well grounded and plenty cleaned. I know from EE work that the HF in these machines is terrible for EMI and sensitive equipment (have had to lift start a bit with the electronics box during an emergency repair), but I would think any good hood would be adequately shielded considering how ubiquitous HF is in TIG So being one to experiment I held the lens unit in my hand and the torch in the other about 1.5 feet away. Tapping the HF would cause it to partially auto dark..and well...after getting a few more seams done later it just flat quit. Something tells me a MCU or transistor somewhere is fried. Lens is staying in the LCD "neutral" state (maybe a shade 4). Turning on would clear this. Going dark would be power applied to the LCD matrix.All signs point to toast Going to try and call Jackson and see what's up. If they tell me to pound sand well...I guess that's a better excuse than any for a digital elite or 9100x. Not having to worry about sending in for warranty if they blow me off will also give me a shot to scope the board and see what really died. Heck...this wouldn't be the first time I've repaired a 1$ SMD part to get a 200$ piece working haha.Anyone else had issues like this?HTP Invertig 221-DV -- get's dragged everywhere.Syncro 200 -- "The Boat Anchor" at the lab.Lincoln 125 MIG
Reply:...and of course, you:manually turned helmet 'on'?played with sensitivity control?That unit only has 2 sensors as opposed to 3 or 4---IOW is canbe wholly easy to block the sensor's view.Last edited by dave powelson; 07-15-2012 at 03:08 PM.Reason: additionBlackbird
Reply:Yeah tried all of that. It flat out won't power on anymore. At this point the lens is bricked.First thing I did when I got is was play with all the settings to feel it out.Arc sensing was working great before it died. Down to 5 amp ss tig on a 40 thou electrode.HTP Invertig 221-DV -- get's dragged everywhere.Syncro 200 -- "The Boat Anchor" at the lab.Lincoln 125 MIG
Reply:It seems to me that using circuitry in a WELDING SHIELD that could be damaged by WELDERS would not be wise engineering.I'd look for another cause.
Reply:That's exactly the thought that first crossed my mind; why make something and not shield it against it's normal op routine. I'm thinking more likely it could be a bad unit, or the weldor who used it before me wasn't careful with it. Maybe a few drops that made it vulnerable. HF was causing it to auto darken with no arc....and appears to have led to it's demise.  No environment changes, gear changes, or method. If it still worked I would test it on lift start.Can't exactly be a complex circuit considering all it does. Few pots and buttons, prolly an 8bit mcu, and ancillary parts.Going to pop it open and check the traces. Good chance the reg or perhaps a power mosfet/bjt got fried with the total lack of start.HTP Invertig 221-DV -- get's dragged everywhere.Syncro 200 -- "The Boat Anchor" at the lab.Lincoln 125 MIG